ACDS V10.0 - Wed Apr 24 00:12:40 CEST 2019
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Detailed Description of I/345 :
Gaia DR2 (Gaia Collaboration, 2018)
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Note : this is the description file of the original catalog.
This HTML page corresponds well to the original description, but some minor
changes in the format may have been introduced in the FITS output
files in order to allow for arithmetic operations on quantities
such as coordinates and times. h:m:s and d:m:s units are normally
converted into degrees, and YYYY-MM-DD into julian days.
Similarly, some slight changes may have been introduced in the
units; the value given in the HTML files supersedes the value indicated in the ReadMe
file for this catalogue.
I/345 Gaia DR2 (Gaia Collaboration, 2018)
================================================================================
Gaia data release 2 (Gaia DR2).
Gaia collaboration
<Astron. Astrophys., 616, A1 (2018)>
=2018A&A...616A...1G
=2018yCat.1345....0G
================================================================================
ADC_Keywords: Surveys ; Stars, standard ; Positional data ; Proper motions ;
Photometry, photographic ; Cross identifications ;
Radial velocities ; Stars, variable ; Minor planets;
Parallaxes, trigonometric
Mission_Name: Gaia
Keywords: catalogs - astrometry - techniques: radial velocities -
stars: fundamental parameters - stars: variables: general -
minor planets, asteroids: general
Abstract:
Gaia Data Release 2. Summary of the contents and survey properties:
We present the second Gaia data release, Gaia DR2, consisting of
astrometry, photometry, radial velocities, and information on as-
trophysical parameters and variability, for sources brighter than
magnitude 21. In addition epoch astrometry and photometry are provided
for a modest sample of minor planets in the solar system.
A summary of the contents of Gaia DR2 is presented, accompanied by a
discussion on the differences with respect to Gaia DR1 and an overview
of the main limitations which are still present in the survey.
Recommendations are made on the responsible use of Gaia DR2 results.
Methods. The raw data collected with the Gaia instruments during the
first 22 months of the mission have been processed by the Gaia Data
Processing and Analysis Consortium (DPAC) and turned into this second
data release, which represents a major advance with respect to Gaia
DR1 in terms of completeness, performance, and richness of the data
products.
Gaia DR2 contains celestial positions and the apparent brightness in G
for approximately 1.7 billion sources. For 1.3 billion of those
sources, parallaxes and proper motions are in addition available. The
sample of sources for which variability information is provided is
expanded to 0.5 million stars. This data release contains four new
elements: broad-band colour information in the form of the apparent
brightness in the GBP (330-680nm) and GRP (630-1050nm) bands is
available for 1.4 billion sources; median radial velocities for some
7 million sources are presented; for between 77 and 161 million
sources estimates are provided of the stellar effective temperature,
extinction, reddening, and radius and luminosity; and for a
pre-selected list of 14000 minor planets in the solar system epoch
astrometry and photometry are presented. Finally, Gaia DR2 also
represents a new materialisation of the celestial reference frame in
the optical, the Gaia-CRF2, which is the first optical reference frame
based solely on extragalactic sources. There are notable changes in
the photometric system and the catalogue source list with respect to
Gaia DR1, and we stress the need to consider the two data releases as
independent.
Gaia DR2 represents a major achievement for the Gaia mission,
delivering on the long standing promise to provide parallaxes and
proper motions for over 1 billion stars, and representing a first step
in the availability of complementary radial velocity and source
astrophysical information for a sample of stars in the Gaia survey
which covers a very substantial fraction of the volume of our galaxy.
The catalogue of radial velocity standard stars
(Soubiran et al., 2018A&A...616A...7S)
The Radial Velocity Spectrometer (RVS) on board of Gaia having no
calibration device, the zero point of radial velocities needs to be
calibrated with stars proved to be stable at the level of 300m/s
during the Gaia observations. A dataset of about 71000 ground-based
radial velocity measurements from five high resolution spectrographs
has been compiled. A catalogue of 4813 stars was built by combining
these individual
measurements. The zero point has been established using asteroids. The
resulting catalogue has 7 observations per star on average on a
typical time baseline of 6 years, with a median standard deviation of
15m/s. A subset of the most stable stars fulfilling the RVS
requirements has been used to establish the zero point of the radial
velocities provided in Gaia DR2. The stars not used for calibration
are used for the RVS data validation.
Description:
Contents of Gaia DR2:
The five-parameter astrometric solution - positions on the sky
(alpha,delta), parallaxes, and proper motions - for more than 1.3
billion (109) sources, with a limiting magnitude of G=21 and a
bright limit of G~=3. Parallax uncertainties are in the range of up
to 0.04 milliarcsecond for sources at G<15, around 0.1mas for
sources with G=17 and at the faint end, the uncertainty is of the
order of 0.7mas at G=20. The corresponding uncertainties in the
respective proper motion components are up to 0.06mas/yr (for
G<15mag), 0.2mas/yr (for G=17mag) and 1.2mas/yr (for G=20mag). The
Gaia DR2 parallaxes and proper motions are based only on Gaia data;
they do no longer depend on the Tycho-2 Catalogue.
Median radial velocities (i.e. the median value over the epochs) for
more than 6 million stars with a mean G magnitude between about 4 and
13 and an effective temperature (Teff) in the range of about 3550 to
6900K. This leads to a full six-parameter solution: positions and
motions on the sky with parallaxes and radial velocities, all combined
with mean G magnitudes. The overall precision of the radial velocities
at the bright end is in the order of 200-300m/s while at the faint
end the overall precision is approximately 1.2km/s for a Teff of
4750K and about 2.5km/s for a Teff of 6500K.
An additional set of more than 200 million sources for which a
two-parameter solution is available: the positions on the sky
(alpha,delta) combined with the mean G magnitude. These sources will
have a positional uncertainty at G=20 of about 2mas, at J2015.5.
G magnitudes for more than 1.5 billion sources, with precisions
varying from around 1 milli-mag at the bright (G<13) end to around 20
milli-mag at G=20. Please be aware that the photometric system for the
G band in Gaia DR2 will be different from the photometric system as
used in Gaia DR1.
GBP and GRP magnitudes for more than 1.1 billion sources, with
precisions varying from a few milli-mag at the bright (G<13) end to
around 200 milli-mag at G=20. Full passband definitions for G, BP and
RP. These passbands are now available for download. A detailed
description is given here. Epoch astrometry for more than 13,000 known
asteroids based on more than 1.5 million CCD observations. 96% of the
along-scan (AL) residuals are in the range -5 to 5mas, and 52% of the
AL residuals are in the range of -1 to 1mas. The observations will be
published in Gaia DR2 and also delivered to the Minor Planet Center
(MPC).
Subject to limitations the effective temperatures Teff for more than
150 million sources brighter than 17th magnitude with effective
temperatures in the range 3000 to 10,000 K. For a subset of these
sources also the line-of-sight extinction AG and reddening E(BP-RP)
will be given, as well as the luminosity and radius.
Lightcurves for more than 500,000 variable sources consisting of
Cepheids, RR Lyrae, Mira and Semi-Regular Candidates as well as
High-Amplitude Delta Scuti, BY Draconis candidates, SX Phoenicis
Candidates and short time scale phenomena.
Planned cross-matches between Gaia DR2 sources on the one hand and
Hipparcos-2, Tycho-2, 2MASS PSC, SDSS DR9, Pan-STARRS1, GSC2.3,
PPM-XL, AllWISE, and URAT-1 data on the other hand.
Catalogue of radial velocity standard stars
(Soubiran et al., 2018A&A..in.prep...):
Individual and combined radial velocity measurements are presented for
4813 stars in rvstdcat.dat and rvstdmes.dat files.
File Summary:
FileName Lrecl Records Explanations
× 80 . This file
× ReadMe 80 . This file
× gaia2.sam 896 1000 GaiaSource DR2 data
× rvstdcat.dat 270 4813 Mean radial velocities on absolute scale
× rvstdmes.dat 76 71225 Original ground-based radial velocity
measurements
× allwise.dat 39 555934 Allwise AGN Gaia DR2 cross-identification
(auxallwiseagngdr2cross_id)
× iers.dat 28 2820 IERS GaiaDR2 cross-identification
(auxiersgdr2crossid)
× cepheid.dat 435 9575 Cepheid stars (vari_cepheid)
× rrlyrae.dat 378 140784 RR Lyrae stars (vari_rrlyrae)
× lpv.dat 94 89617 Long Period Variable stars
(varilongperiod_variable)
× varres.dat 70 363969 Variability classification results of all
classifiers, identified by the
classifierName column (variclassifierresult)
× shortts.dat 91 3018 Short-timescale sources (varishorttimescale)
× tsstat.dat 432 550737 Statistical parameters of time series, using
only transits not rejected
(varitimeseries_statistics)
× numtrans.dat 43 550737 Calibrated FoV transit photometry from CU5,
consolidated and provided by CU7 for variable
stars in Gaia DR2 (epoch_photometry, part 1)
× transits.dat 365 17712391 Calibrated FoV transit photometry for CU5,
consolidated and provided by CU7 for variable
stars in Gaia DR2 (epoch_photometry, part 2)
× rm.dat 137 147535 Rotation period in segment, part 1
(varirotationmodulation)
× rmseg.dat 276 583988 Rotation period in segment, part 2
(varirotationmodulation)
× rmout.dat 33 990561 Rotation period in segment, part 3
(varirotationmodulation)
× ssoobj.dat 59 14099 *Data related to Solar System objects observed
by Gaia (sso_source)
× ssoorb.dat 181 14099 *Auxiliary information on asteroid orbits and
basic photometric parameters (auxssoorbits)
× ssores.dat 155 1977702 *Residuals with respect to an orbital fit
considering only the Gaia observations
(auxssoorbit_residuals)
× ssoobs.dat 404 1977702 *Solar System object observations
(sso_observation)
Note on ssoobj.dat: The quantities in the table are derived from data
reduction and are associated to single objects.
Note on ssoorb.dat: from the astorb database (Cat. B/astorb).
Note on ssores.dat: Each entry has a corresponding record in the table
ssoobs.dat. A flag is given, indicating if the observation has been rejected
by the fit procedure.
Note on ssoobs.dat: Each table line contained data obtained during the transit
of the source on a single CCD, during a single transit. The corresponding
epoch is provided. Data not varying within the transit are repeated
identically for all single observations of that transit.
See also:
B/astorb : Orbits of Minor Planets (Bowell+ 2014)
II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)
II/328 : AllWISE Data Release (Cutri+ 2013)
I/337 : Gaia DR1 (Gaia Collaboration, 2016)
I/347 : Distances to 1.33 billion stars in Gaia DR2 (Bailer-Jones+, 2018)
J/A+A/616/A12 : Gaia DR2 sources in GC and dSph (Gaia Collaboration+, 2018)
J/A+A/620/A127 : Cassification of RR Lyrae and Cepheid (Molnar+, 2018)
J/A+A/620/A128 : Gaia DR2 study of Herbig Ae/Be stars (Vioque+, 2018)
Byte-by-byte Description of file: gaia2.sam
Bytes Format Units Label Explanations
1- 28 A28 --- DR2Name Unique source designation (unique across
all Data Releases)
(Gaia DR2 NNNNNNNNNNNNNNNNNNN)
(designation) (1)
30- 44 F15.11 deg RAdeg Barycentric right ascension (ICRS)
at Ep=2015.5 (ra)
46- 60 F15.11 deg DEdeg Barycentric declination (ICRS)
at Ep=2015.5 (dec)
62- 80 I19 --- SolID Solution Identifier (solution_id) (G1)
82-100 I19 --- Source Unique source identifier (unique within
a particular Data Release)
(source_id) (G2)
102-111 I10 --- RandomI Random index used to select subsets
(random_index) (2)
113-118 F6.1 yr Epoch [2015.5] Reference epoch (ref_epoch)
120-126 F7.4 mas e_RAdeg Standard error of right ascension
(e_RA*cosDE) (ra_error)
128-134 F7.4 mas e_DEdeg Standard error of declination (dec_error)
136-145 F10.4 mas Plx ? Absolute stellar parallax (parallax)
147-152 F6.4 mas e_Plx ? Standard error of parallax
(parallax_error)
154-163 F10.4 --- RPlx ? Parallax divided by its error
(parallaxovererror)
165-173 F9.3 mas/yr pmRA ? Proper motion in right ascension
direction (pmRA*cosDE) (pmra) (3)
175-179 F5.3 mas/yr e_pmRA ? Standard error of proper motion in right
ascension direction (pmra_error)
181-189 F9.3 mas/yr pmDE ? Proper motion in declination direction
(pmdec) (4)
191-195 F5.3 mas/yr e_pmDE ? Standard error of proper motion in
declination direction (pmdec_error)
197-203 F7.4 --- RADEcor Correlation between right ascension and
declination (radeccorr)
205-211 F7.4 --- RAPlxcor ? Correlation between right ascension and
parallax (raparallaxcorr)
213-219 F7.4 --- RApmRAcor ? Correlation between right ascension and
proper motion in right ascension
(rapmracorr)
221-227 F7.4 --- RApmDEcor ? Correlation between right ascension and
proper motion in declination
(rapmdeccorr)
229-235 F7.4 --- DEPlxcor ? Correlation between declination and
parallax (decparallaxcorr)
237-243 F7.4 --- DEpmRAcor ? Correlation between declination and
proper motion in right ascension
(decpmracorr)
245-251 F7.4 --- DEpmDEcor ? Correlation between declination and
proper motion in declination
(decpmdeccorr)
253-259 F7.4 --- PlxpmRAcor ? Correlation between parallax and proper
motion in right ascension
(parallaxpmracorr)
261-267 F7.4 --- PlxpmDEcor ? Correlation between parallax and proper
motion in declination
(parallaxpmdeccorr)
269-275 F7.4 --- pmRApmDEcor ? Correlation between proper motion in
right ascension and proper motion in
declination (pmrapmdeccorr)
277-280 I4 --- NAL Total number of observations AL
(astrometricnobs_al) (6)
282-285 I4 --- NAC Total number of observations AC
(astrometricnobs_ac) (7)
287-290 I4 --- NgAL Number of good observations AL
(astrometricngoodobsal) (8)
292-294 I3 --- NbAL Number of bad observations AL
(astrometricnbadobsal) (9)
296-304 F9.4 --- gofAL Goodness of fit statistic of model wrt
along-scan observations
(astrometricgofal) (10)
306-316 F11.2 --- chi2AL AL chi-square value
(astrometricchi2al) (11)
318-323 F6.3 mas epsi Excess noise of the source
(astrometricexcessnoise) (12)
325-334 E10.3 --- sepsi Significance of excess noise
(astrometricexcessnoise_sig) (13)
336-337 I2 --- Solved Which parameters have been solved for?
(astrometricparamssolved) (14)
339 I1 --- APF Primary or secondary
(astrometricprimaryflag) (15)
341-348 F8.4 mas-2 WAL Mean astrometric weight of the source
(astrometricweightal) (16)
350-356 F7.4 um-1 pscol ? Astrometrically determined pseudocolour
of the source
(astrometricpseudocolour) (17)
358-363 F6.4 um-1 e_pscol ? Standard error of the pseudocolour of
the source
(astrometricpseudocolour_error)
365-370 F6.3 --- fvarpi Mean Parallax factor AL
(meanvarpifactor_al)
372-374 I3 --- MatchObsA Matched FOV transits used in the AGIS
solution
(astrometricmatchedobservations) (18)
376-377 I2 --- Nper Number of visibility periods used in
Astrometric solution
(visibilityperiodsused)
379-389 E11.6 mas amax The longest semi-major axis of the 5-d
error ellipsoid
(astrometricsigma5dmax) (19)
391 I1 --- type [0/3] The type of the source mainly used
for frame rotation
(framerotatorobject_type) (20)
393-395 I3 --- MatchObs The total number of FOV transits matched
to this source (matched_observations)
397 I1 --- Dup [0/1] Source with duplicate sources
(duplicated_source) (21)
399-402 I4 --- o_Gmag Number of observations contributing to G
photometry (photgn_obs) (22)
404-414 E11.5 e-/s FG G-band mean flux (photgmean_flux)
416-426 E11.5 e-/s e_FG Error on G-band mean flux
(photgmeanfluxerror)
428-436 F9.3 --- RFG G-band mean flux divided by its error
(photgmeanfluxover_error)
438-446 F9.6 mag Gmag G-band mean magnitude (Vega)
(photgmean_mag) (23)
448-450 I3 --- o_BPmag Number of observations contributing to
BP photometry (photbpn_obs) (24)
452-462 E11.5 e-/s FBP ? Mean flux in the integrated BP band
(photbpmean_flux)
464-474 E11.5 e-/s e_FBP ? Error on the integrated BP mean flux
(photbpmeanfluxerror) (25)
476-484 F9.3 --- RFBP ? Integrated BP mean flux divided by its
error (photbpmeanfluxover_error)
486-494 F9.6 mag BPmag ? Integrated BP mean magnitude (Vega)
(photbpmean_mag) (26)
496-498 I3 --- o_RPmag ? Number of observations contributing to
RP photometry (photrpn_obs) (27)
500-510 E11.5 e-/s FRP ? Mean flux in the integrated RP band
(photrpmean_flux)
512-522 E11.5 e-/s e_FRP ? Error on the integrated RP mean flux
(photrpmeanfluxerror) (28)
524-532 F9.3 --- RFRP ? Integrated RP mean flux divided by its
error (photrpmeanfluxover_error)
534-542 F9.6 mag RPmag ? Integrated RP mean magnitude (Vega)
(photrpmean_mag) (29)
544-548 F5.3 --- E(BR/RP) ? BP/RP excess factor
(photbprpexcessfactor)
550 I1 --- Mode Photometry processing mode
(photprocmode)
552-560 F9.6 mag BP-RP ? BP-RP colour
(photBpMeanMag-photRMeanMag) (bp_rp)
562-570 F9.6 mag BP-G ? BP-G colour (photBpMeanMag-photGMeanMag)
(bp_g)
572-580 F9.6 mag G-RP ? G-RP colour (photGMeanMag-photRpMeanMag)
(g_rp)
582-588 F7.2 km/s RV ? Spectroscopic radial velocity in the
solar barycentric reference frame
(radial_velocity)
590-594 F5.2 km/s e_RV ? Radial velocity error
(radialvelocityerror) (30)
596-598 I3 --- o_RV Number of transits used to compute radial
velocity (rvnbtransits)
600-605 F6.1 K Tefftemp ? Teff of the template used to compute
radial velocity (rvtemplateteff) (36)
607-610 F4.1 [cm/s2] loggtemp ? logg of the template used to compute
radial velocity (rvtemplatelogg) (36)
612-615 F4.1 --- [Fe/H]temp ? Fe/H of the template used to compute
radial velocity (rvtemplatefe_h) (36)
617-629 A13 --- Var Photometric variability flag
(photvariableflag) (31)
631-644 F14.10 deg GLON Galactic longitude (l) (32)
646-659 F14.10 deg GLAT Galactic latitude (b) (32)
661-674 F14.10 deg ELON Ecliptic longitude (ecl_lon) (33)
676-689 F14.10 deg ELAT Ecliptic latitude (ecl_lat) (33)
691-696 I6 --- fPriam ? Flags for the Apsis-Priam results
(priam_flags) (34)
698-704 F7.2 K Teff ? Stellar effective temperature
(estimate from Apsis-Priam) (teff_val)
706-712 F7.2 K b_Teff ? Uncertainty (lower) on Teff estimate
from Apsis-Priam (16th percentile)
(teffpercentilelower)
714-720 F7.2 K B_Teff ? Uncertainty (upper) on Teff estimate
from Apsis-Priam (84th percentile)
(teffpercentileupper)
722-727 F6.4 mag AG ? Estimate of extinction in the G band
from Apsis-Priam (agval)
729-734 F6.4 mag b_AG ? Uncertainty (lower) on AG estimate from
Apsis-Priam (16th percentile)
(agpercentile_lower)
736-741 F6.4 mag B_AG ? Uncertainty (upper) on AG estimate from
Apsis-Priam (84th percentile)
(agpercentile_upper)
743-748 F6.4 mag E(BP-RP) ? Estimate of redenning E(BP-RP) from
Apsis-Priam (ebpminrpval)
750-755 F6.4 mag b_E(BP-RP) ? Uncertainty (lower) on E(BP-RP) estimate
from Apsis-Priam (16th percentile)
(ebpminrppercentile_lower)
757-762 F6.4 mag B_E(BP-RP) ? Uncertainty (upper) on E(BP-RP) estimate
from Apsis-Priam (84th percentile)
(ebpminrppercentile_upper)
764-769 I6 --- fFLAME ? Flags for the Apsis-FLAME results
(flame_flags) (35)
771-776 F6.2 solRad Rad ? Estimate of radius from Apsis-FLAME
(radius_val)
778-783 F6.2 solRad b_Rad ? Uncertainty (lower) on radius estimate
from Apsis-FLAME (16th percentile)
(radiuspercentilelower)
785-791 F7.2 solRad B_Rad ? Uncertainty (upper) on radius estimate
from Apsis-FLAME (84th percentile)
(radiuspercentileupper)
793-801 F9.3 solLum Lum ? Esimate of luminosity from Apsis-FLAME
(lum_val)
803-811 F9.3 solLum b_Lum ? Uncertainty (lower) on luminosity
estimate from Apsis-FLAME
(16th percentile) (lumpercentilelower)
813-821 F9.3 solLum B_Lum ? Uncertainty (upper) on luminosity
estimate from Apsis-FLAME
(84th percentile) (lumpercentileupper)
823-837 F15.11 deg RAJ2000 Barycentric right ascension (ICRS) at
Ep=2000.0 (added by CDS) (ra_epoch2000)
839-845 F7.4 mas e_RAJ2000 Standard error of right ascension
(e_RA*cosDE) (added by CDS)
(raepoch2000error)
847-861 F15.11 deg DEJ2000 Barycentric declination (ICRS) at
Ep=2000.0 (added by CDS) (dec_epoch2000)
863-869 F7.4 mas e_DEJ2000 Standard error of declination
(added by CDS) (decepoch2000error)
871-878 F8.6 mag e_Gmag Standard error of G-band mean magnitude
(Vega) (added by CDS)
(photgmeanmagerror) (37)
880-887 F8.6 mag e_BPmag ? Standard error of BP mean magnitude
(Vega) (added by CDS)
(photbpmeanmagerror) (37)
889-896 F8.6 mag e_RPmag ? Standard error of RP mean magnitude
(Vega) (added by CDS)
(photrpmeanmagerror) (37)
Note (1): A source designation, unique across all Gaia Data Releases, that is
constructed from the prefix "Gaia DRx" followed by a string of digits
corresponding to source_id (3 space-separated words in total). Note that the
integer source identifier source_id is NOT guaranteed to be unique across Data
Releases; moreover it is not guaranteed that the same astronomical source will
always have the same source_id in different Data Releases. Hence the only safe
way to compare source records between different Data Releases in general is to
check the records of proximal source(s) in the same small part of the sky.
Note (2): Random index which can be used to select smaller subsets of the data
that are still representative. The column contains a random permutation of the
numbers from 0 to N-1, where N is the number of rows. The random index can be
useful for validation (testing on 10 different random subsets), visualization
(displaying 1% of the data), and statistical exploration of the data, without
the need to download all the data.
Note (3): Proper motion in right ascension µ{alpha}*~µ{alpha}cos{delta}
of the source in ICRS at the reference epoch ref_epoch
. This is the tangent
plane projection of the proper motion vector in the direction of increasing
right ascension.
Note (4): Proper motion in declination µ_{delta} of the source at the
reference epoch ref_epoch
. This is the tangent plane projection of the proper
motion vector in the direction of increasing declination.
Note (6): Total number of AL observations (= CCD transits) used in the
astrometric solution of the source, independent of their weight. Note that some
observations may be strongly downweighted (see astrometricNBadObsAl).
Note (7): Total number of AC observations (= CCD transits) used in the
astrometric solution of the source, independent of their weight. Note that some
observations may be strongly downweighted (see astrometricNBadObsAc). Nearly
all sources having G<13 will have AC observations from 2d windows, while
fainter than that limit only ~1% of transit observations (the so-called
"calibration faint stars") are assigned 2d windows resulting in AC
observations.
Note (8): Number of AL observations (= CCD transits) that were not strongly
downweighted in the astrometric solution of the source. Strongly downweighted
observations (with downweighting factor w<0.2) are instead counted in
astrometricNBadObsAl. The sum of astrometricNGoodObsAl and
astrometricNBadObsAl equals astrometricNObsAl, the total number of AL
observations used in the astrometric solution of the source.
Note (9): Number of AL observations (= CCD transits) that were strongly
downweighted in the astrometric solution of the source, and therefore
contributed little to the determination of the astrometric parameters.
An observation is considered to be strongly downweighted if its downweighting
factor w<0.2, which means that the absolute value of the astrometric residual
exceeds 4.83 times the total uncertainty of the observation, calculated as the
quadratic sum of the centroiding uncertainty, excess source noise, and excess
attitude noise.
Note (10): Goodness-of-fit statistic of the astrometric solution for the source
in the along-scan direction. This is the 'gaussianized chi-square', which for
good fits should approximately follow a normal distribution with zero mean
value and unit standard deviation. Values exceeding, say, +3 thus indicate a
bad fit to the data.
This statistic is computed according to the formula
astrometricGofAl
=(9{nu}/2)1/2 [({chi}2/{nu})1/3^ + 2/(9{nu})-1]
where {chi}2=astrometricChi2Al is theAL chi-square statistic and
{nu}=astrometricNGoodObsAl-N is the number of degrees of freedom for a source
update. Here N=5 is the number of astrometric parameters. Note that only "good"
(i.e. not strongly downweighted) observations are included in {chi}2 and
{nu}.
The above formula is the well-known cube-root transformation of the chi-square
variable (E.B. Wilson & M.M. Hilferty 1931, Proc. National Academy of Science,
17, 684). It is usually quoted to be valid for {nu}>30, but is in fact useful
for much smaller {nu}. This transformation of ({chi}2, {nu}) eliminates the
inconvenience of having the distribution (and hence the significance levels)
depend on the additional variable {nu}, which is generally not the same for
different sources.
An alternative indicator of bad fits is the astrometricExcessNoise. In AGIS the
source update deals with bad fits by adding astrometricExcessNoise to the
formal observation noise. This reduces the weight of the observations and
inflates the covariance of the estimated astrometric parameters
correspondingly. However, the chi-square values used to calculate
astrometricGofAl do not take into account the astrometricExcessNoise, and
astrometricGofAl can therefore always be used as a goodness-of-fit indicator of
the source solution in AGIS.
Note (11): Description:Astrometric goodness-of-fit ({chi}2) in the AL
direction. {chi}2 values were computed for the 'good' AL observations of the
source, without taking into account the astrometricExcessNoise (if any) of the
source. They do however take into account the attitude excess noise (if any)
of each observation.
Note (12):This is the excess noise {epsilon}i of the source. It measures the
disagreement, expressed as an angle, between the observations of a source and
the best-fitting standard astrometric model (using five astrometric
parameters). The assumed observational noise in each observation is
quadratically increased by {epsilon}i in order to statistically match the
residuals in the astrometric solution. A value of 0 signifies that the source
is astrometrically well-behaved, i.e. that the residuals of the fit
statistically agree with the assumed observational noise. A positive value
signifies that the residuals are statistically larger than expected.
The significance of {epsilon}i is given by astrometricExcessNoiseSig (D).
If D<=2 then {epsilon}i is probably not significant, and the source may be
astrometrically well-behaved even if {epsilon}i is large. The excess noise
{epsilon}i may absorb all kinds of modelling errors that are not accounted for
by the observational noise (image centroiding error) or the excess attitude
noise. Such modelling errors include LSF and PSF calibration errors, geometric
instrument calibration errors, and part of the high-frequency attitude noise.
These modelling errors are particularly important in the early data releases,
but should decrease as the astrometric modelling of the instrument and attitude
improves over the years.
Additionally, sources that deviate from the standard five-parameter astrometric
model (e.g. unresolved binaries, exoplanet systems, etc.) may have positive
{epsilon}i. Given the many other possible contributions to the excess noise,
the user must study the empirical distributions of {epsilon}i and D to make
sensible cutoffs before filtering out sources for their particular application.
Note (13): Adimensionless measure (D) of the significance of the calculated
astrometricExcessNoise ({epsilon}i). A value D>2 indicates that the given
{epsilon}i is probably significant. For good fits in the limit of a large
number of observations, D should be zero in half of the cases and approximately
follow the positive half of a normal distribution with zero mean and unit
standard deviation for the other half. Consequently, D is expected to be
greater than 2 for only a few percent of the sources with well-behaved
astrometric solutions. In the early data releases {epsilon}i will however
include instrument and attitude modelling errors that are statistically
significant and could result in large values of {epsilon}i and D. The user
must study the empirical distributions of these statistics and make sensible
cutoffs before filtering out sources for their particular application.
Note (14): This is a binary code indicating which astrometric parameters were
estimated for the source. A set bit means the parameter was estimated.
The least-significant bit represents {alpha}, the next bits {delta}, {pi},
µ{alpha}*, and µ{delta}.
For Gaia DR2the only relevant values are
- astrometricParamsSolved=31 (binary 11111):
all five astrometric parameters were estimated
- astrometricParamsSolved=3 (binary 11):
only position ({alpha}, {delta}) was estimated
Note (15): Flag indicating if this source was used as a primary source (true) or
secondary source (false). Only primary sources contribute to the estimation of
attitude, calibration, and global parameters. The estimation of source
parameters is otherwise done in exactly the same way for primary and
secondary sources.
Note (16): Mean astrometric weight of the source in the AL direction.
The mean astrometric weight of the source is calculated as per Eq. (119).
Note (17): Colour of the source assumed in the final astrometric processing.
The astrometricPseudoColour is defined to be equivalent to the effective
wavenumber of the photon flux distribution in the astrometric (G) band, and is
measured in um-1. The value given in this field was astrometrically
determined in a preliminary solution, using the chromatic displacement of
image centroids calibrated by means of the effective wavenumbers ({nu}eff) of
primary sources calculated from BP and RP magnitudes. The field is empty when
no such determination was possible, in which case a default value of
1.6um-1 was assumed.
Note (18): The number of FOV transits matched to this source, counting only the
transits containing CCD observations actually used to compute the astrometric
solution. This number will always be equal to or smaller than the
matchedObservations, the difference being the FOV transits that were not used
in the astrometric solution because of bad data or excluded time intervals.
Note (19): The longest principal axis in the 5-dimensional error ellipsoid.
This is a 5-dimensional equivalent to the semi-major axis of the position error
ellipse and is therefore useful for filtering out cases where one of the five
parameters, or some linear combination of several parameters, is particularly
ill-determined. It is measured in mas and computed as the square root of the
largest singular value of the scaled 5x5 covariance matrix of the astrometric
parameters. The matrix is scaled so as to put the five parameters on a
comparable scale, taking into account the maximum along-scan parallax factor
for the parallax and the time coverage of the observations for the proper
motion components. If C is the unscaled covariance matrix, the scaled matrix
is SCS, where S=diag(1,1,sin{xi},T/2,T/2), {xi}=45° is the solar aspect
angle in the nominal scanning law, and T the time coverage of the data used in
the solution. T=1.75115 yr for Gaia DR2. astrometricSigma5dMax is given for
both 5-parameter and 2-parameter solutions, as its size is one of the criteria
for accepting or rejecting the 5-parameter solution. In case of a 2-parameter
solution (astrometricParamsSolved=3) it gives the value for the rejected
5-parameter solution, and can then be arbitrarily large.
Note (20): This field is non-zero if the source was used to define the reference
frame of the positions and proper motions.
The values used are:
0 = An ordinary source not used for the reference frame determination
2 = The optical counterpart of an extragalactic radio source with accurately
known VLBI position in ICRF. This is used to determine the orientation
of the reference frame at the reference epoch, but also contributes to
the determination of a non-rotating frame.
3 = An extragalactic source (AGN or quasar) that was used to determine a
kinematically non-rotating celestial frame.
Note (21): During data processing, this source happened to be duplicated and
only one source identifier has been kept. Observations assigned to the
discarded source identifier(s) were not used. This may indicate observational,
cross-matching or processing problems, or stellar multiplicity, and probable
astrometric or photometric problems in all cases. In Gaia DR1 and DR2, for
close doubles with separations below some 2 arcsec, truncated windows have not
been processed, neither in astrometry nor photometry. The transmitted window
is centred on the brighter part of the acquired window, so the brighter
component has a better chance to be selected, even when processing the fainter
transit. If more than two images are contained in a window, the result of the
image parameter determination is unpredictable in the sense that it might
refer to either (or neither) image, and no consistency is assured.
Note (22): Number of observations (CCD transits) that contributed to the G mean
flux and mean flux error.
Note (23): This is computed from the G-band mean flux applying the magnitude
zero-point in the Vega scale. No error is provided for this quantity as the
error distribution is only symmetric in flux space. This converts to an
asymmetric error distribution in magnitude space which cannot be represented
by a single error value.
Note (24): Number of observations (CCD transits) that contributed to the
integrated BP mean flux and mean flux error.
Note (25): Error on the mean flux in the integrated BP band (errors are computed
from the dispersion about the weighted mean of input calibrated photometry).
Note (26): Mean magnitude in the integrated BP band. This is computed from the
BP-band mean flux applying the magnitude zero-point in the Vega scale.
No error is provided for this quantity as the error distribution is only
symmetric in flux space. This converts to an asymmetric error distribution in
magnitude space which cannot be represented by a single error value.
Note (27): Number of observations (CCD transits) that contributed to the
integrated RP mean flux and mean flux error.
Note (28): Error on the mean flux in the integrated RP band (errors are computed
from the dispersion about the weighted mean of input calibrated photometry).
Note (29): Mean magnitude in the integrated RP band. This is computed from the
RP-band mean flux applying the magnitude zero-point in the Vega scale.
No error is provided for this quantity as the error distribution is only
symmetric in flux space. This converts to an asymmetric error distribution in
magnitude space which cannot be represented by a single error value.
Note (30): The radialVelocityError is the error on the median to which a
constant noise floor of 0.11km/s has been added in quadrature to take into
account the calibration contribution.
In detail, radialVelocityError=sqrt({sigma}^2{Vrad}+0.11^2) where
{sigma}{Vrad} is the error on the median:
{sigma}{Vrad} =
sqrt({pi}/2).{sigma}(V_rad^t)/sqrt(nbtransits)
where {sigma}(V_rad^t) is the standard deviation of the epoch radial
velocities and rvNbTransits the number of transits for which a
V_rad^t has been obtained.
Note (31): Flag indicating if variability was identified in the photometric
data:
- "NOT_AVAILABLE" = source not processed and/or exported to catalogue
- "CONSTANT" = Source not identified as variable
- "VARIABLE" = source identified and processed as variable,
see Vari* tables (cepheid.dat, rrlyrae.dat, lpv.dat,
shortts.dat)
Note that for this data release only a subset of (variable) sources was
processed and/or exported, so for many (known) variable sources this flag is
set to "NOT AVAILABLE". No "CONSTANT" sources were exported either.
Note (32): Galactic longitude and latitude of the object at reference epoch
refEpoch, see Section [ssec:cu3astintrogalactic] of the release documentation
for conversion details.
Note (33): Ecliptic longitude and latitude of the object at reference epoch
refEpoch, obtained from the equatorial coordinates using the transformation
defined in Section 1.5.3 of "The Hipparcos and Tycho Catalogues", ESA SP-1200,
Volume 1 (ESA, 1997).
Note (34): Flags describing the status of the astrophysical parameters Teff, AG
and E[BP-RP] (i.e. those determined by Apsis-Priam). They are described in
Chapter [chap:cu8par] of the release documentation.
Note (35): Flags describing the status of the astrophysical parameters radius
and luminosity (i.e. those determined by Apsis-FLAME). They are described in
Chapter [chap:cu8par] of the release documentation.
Note (36): The purpose of these parameters is to provide information on the
synthetic spectrum used to determine radial_velocity, and not to provide an
estimation of the star parameter.
Note (37): The single-valued errors added by CDS do not always reflect
accurately the magnitude errors. Indeed, the errors are only symmetric in
flux space and ideally a +1 sigma and -1 sigma would be needed to properly
describe the magnitude uncertainties. For the G-band this effect is probably
not very severe, but for BP and RP this may become significant at the faint
end.
Byte-by-byte Description of file: rvstdcat.dat
Bytes Format Units Label Explanations
2- 23 A22 --- ID Star ID (HIP, TYC or 2MASS)
25- 32 F8.3 km/s RV [-382.272/339.061] Mean Radial Velocity
35- 41 F7.4 km/s eRV [0.0001/0.2157] Internal error of RV
44- 50 F7.4 km/s s_RV [0/1.6164] Standard deviation of RV
53- 59 F7.4 km/s e_RV [0.0001/0.6374] Uncertainty of RV
61- 65 I5 d Tbase Time baseline of the N observations
67- 71 I5 d JDm Mean Julian Day of observations (JD-2400000)
73- 75 I3 --- N Number of ground-based radial velocities
79- 97 I19 --- Source ?=0 Source ID in Gaia DR2
99-102 A4 --- Flag Calibration or validation status (1)
104-110 F7.2 km/s RVS [-382.02/339.66]?=-999.99 Gaia DR2
Radial Velocity
112-116 F5.2 km/s e_RVS [0.11/19.07]?=-9.99 Gaia DR2
Radial Velocity error
118-120 I3 --- o_RVS [0/92] Number of RVS transits
122-143 A22 --- 2MASS ? 2MASS ID (2MASSJHHMMSSss+DDMMSSS)
145-151 F7.3 mag Jmag ?=-9.999 2MASS J magnitude
153-159 F7.3 mag Hmag ?=-9.999 2MASS H magnitude
161-167 F7.3 mag Kmag ?=-9.999 2MASS K magnitude
169-175 F7.3 mag e_Jmag ?=-9.999 2MASS J magnitude error
177-183 F7.3 mag e_Hmag ?=-9.999 2MASS H magnitude error
185-191 F7.3 mag e_Kmag ?=-9.999 2MASS K magnitude error
193-195 A3 --- Qflag 2MASS Qflag
199-208 F10.6 deg RAdeg Right ascension (ICRS) (2)
211-219 F9.5 deg DEdeg Declination (ICRS) (2)
221 A1 --- --- [J]
222-227 F6.1 yr Epoch Epoch for RAdeg and DEdeg
229-233 F5.2 mag Bmag ? Simbad B magnitude
235-239 F5.2 mag Vmag ? Simbad V magnitude
241-255 A15 --- SpType ? Simbad spectral type
257-270 A14 --- otype Simbad object type
Note (1): Flag as follows:
CAL1 = calibrator for DR2 and DR3
CAL2 = calibrator for DR2 not for DR3
CAL3 = calibrator for DR3 not for DR2
VAL = validation star
Note (2): RA and DEC come from Gaia DR2 (ICRS, Epoch=J2015.5) when available
(source_id>0) or from Simbad (ICRS, Epoch=J2000.0).
Byte-by-byte Description of file: rvstdmes.dat
Bytes Format Units Label Explanations
2- 23 A22 --- ID Star ID (HIP, TYC or 2MASS)
25 A1 --- Instr Instrument (1)
27- 31 I5 d JD Julian Day of observation (JD-2400000)
33- 40 F8.3 km/s RV Radial Velocity
42- 48 F7.4 km/s e_RV Radial Velocity error
50- 51 A2 --- Mask Spectral type of the mask used for the CCF (2)
53- 76 A24 --- Idspec ? Identification number in public archive (3)
Note (1): Instrument code as follows:
S = SOPHIE
E = ELODIE
C = CORALIE
N = NARVAL
H = HARPS
Note (2): Mask is unknown when the measurement comes from the AMBRE-HARPS
catalogue (de Pascale et al., 2014A&A...570A..68D)
Note (3): Internal sequence number in SOPHIE archive (seq), or running number
(immanum) and dataset in ELODIE archive, or original file name
(ORIGFILE) in ESO-HARPS archive.
Byte-by-byte Description of file: allwise.dat
Bytes Format Units Label Explanations
1- 19 A19 --- Allwise WISE All-Sky Release Catalog name, based on
J2000 position (allwise_name)
21- 39 I19 --- Source Gaia source identifier (source_id)
Byte-by-byte Description of file: iers.dat
Bytes Format Units Label Explanations
1- 8 A8 --- IERS International Earth Rotation and Reference
Systems Service name (HHMM+DDd, B1950
equinox) (iers_name)
10- 28 I19 --- Source Gaia source identifier (source_id) (G3)
Byte-by-byte Description of file: cepheid.dat
Bytes Format Units Label Explanations
1- 5 A5 --- TBest Best type classification estimate
(typebestclassification) (1)
7- 12 A6 --- TBest2 Best subclassification estimate
(type2bestsub_classification) (2)
14- 27 A14 --- Mbest Best mode classification estimate
(modebestclassification) (3)
29- 33 A5 --- Mbest2 Best multi mode DCEP classification
(multimodebest_classification) (4)
35- 52 I18 --- SolID Solution Identifier (solution_id) (G1)
54- 72 I19 --- Source Unique source identifier (source_id) (G2)
74- 85 F12.8 d Pf ? Period corresponding to the fundamental
pulsation mode (for multi mode pulsators)
in the G band time series (pf) (G5)
87- 96 F10.8 d e_Pf ? Uncertainty of the Pf period (pf_error) (G6)
98-107 F10.8 d P1O ? Period corresponding to the first overtone
pulsation mode (for multi mode pulsators) in
the G band time series (p1_o) (G7)
109-118 F10.8 d e_P1O ? Uncertainty of the P2O period
(p1oerror) (G6)
120-129 F10.8 d P2O ? Period corresponding to the second overtone
pulsation mode (for multi mode pulsators) in
the G band time series (p2_o) (G8)
131-140 F10.8 d e_P2O ? Uncertainty of the P2O period
(p2oerror) (G6)
142-151 F10.8 d P3O ? Period corresponding to the third overtone
pulsation mode (for multi mode pulsators) in
the G band time series (p3_o) (G9)
153-162 F10.8 d e_P3O ? Uncertainty of the P3O period
(p3oerror) (G6)
164-176 F13.8 d EpG Epoch of the maximum of the light curve in
the G band (JD=2455197.5) (epoch_g) (G10)
178-187 F10.8 d e_EpG Uncertainty on the epoch parameter epoch G
(epochgerror)
189-201 F13.8 d EpBP Epoch of the maximum of the light curve in
the BP band (JD=2455197.5) (epoch_bp) (G10)
203-212 F10.8 d e_EpBP Uncertainty on the epoch parameter epoch BP
(epochbperror)
214-226 F13.8 d EpRP Epoch of the maximum of the light curve in
the RP band (JD=2455197.5) (epoch_rp) (G10)
228-237 F10.8 d e_EpRP Uncertainty on the epoch parameter epoch RP
(epochrperror)
239-247 F9.6 mag Gmag Intensity-averaged magnitude in the G band
(intaverageg)
249-256 F8.6 mag e_Gmag Uncertainty on Intensity-averaged magnitude in
the G band (intaverageg_error) (G11)
258-266 F9.6 mag BPmag ? Intensity-averaged magnitude in the BP band
(intaveragebp)
268-275 F8.6 mag e_BPmag ? Uncertainty on Intensity-averaged magnitude
in the BP band (intaveragebp_error) (G11)
277-285 F9.6 mag RPmag ? Intensity-averaged magnitude in the RP band
(intaveragerp)
287-294 F8.6 mag e_RPmag ? Uncertainty on Intensity-averaged magnitude
in the RP band (intaveragerp_error) (G11)
296-303 F8.6 mag AmpG Peak-to-peak amplitude of the G band light
curve (peaktopeak_g) (G12)
305-312 F8.6 mag e_AmpG Uncertainty on the AmpG parameter
(peaktopeakgerror) (G13)
314-321 F8.6 mag AmpBP ? Peak-to-peak amplitude of the BP band light
curve (peaktopeak_bp) (G12)
323-330 F8.6 mag e_AmpBP ? Uncertainty on the AmpBP parameter
(peaktopeakbperror) (G13)
332-339 F8.6 mag AmpRP ? Peak-to-peak amplitude of the RP band light
curve (peaktopeak_rp) (G12)
341-348 F8.6 mag e_AmpRP ? Uncertainty on the AmpRP parameter
(peaktopeakrperror) (G13)
350-354 F5.2 [-] [Fe/H] ? Metallicity of the star from the Fourier
parameters of the light curve
(metallicity) (G14)
356-359 F4.2 [-] e_[Fe/H] ? Uncertainty of the metallicity parameter
(metallicity_error)
361-367 F7.5 --- R21G ? Fourier decomposition parameter r21G: A2/A1
(for G band) (r21_g) (G15)
369-375 F7.5 --- e_R21G ? Uncertainty on the r21G parameter: A2/A1
(for G band) (r21gerror) (G16)
377-383 F7.5 --- R31G ? Fourier decomposition parameter A3/A1
(for G band) (r31_g) (G15)
385-391 F7.5 --- e_R31G ? Uncertainty on the r31G parameter: A3/A1
(for G band) (r31gerror) (G16)
393-399 F7.5 rad phi21G ? Fourier decomposition parameter
phi21G: phi2-2*phi1 (for G band)
(phi21_g) (G17)
401-407 F7.5 rad e_phi21G ? Uncertainty on the phi21G parameter
(for G band) (phi21gerror) (G18)
409-415 F7.5 rad phi31G ? Fourier decomposition parameter
phi31G: phi3-3*phi1 (for G band)
(phi31_g) (G17)
417-423 F7.5 rad e_phi31G ? Uncertainty on the phi31G parameter
(for G band) (phi31gerror) (G18)
425-427 I3 --- o_EpG Number of G FoV epochs used in the fitting
algorithm (numcleanepochs_g)
429-431 I3 --- o_EpBP Number of BP epochs used in the fitting
algorithm (numcleanepochs_bp)
433-435 I3 --- o_EpRP Number of RP epochs used in the fitting
algorithm (numcleanepochs_rp)
Note (1): Classification of a Cepheid into "DCEP", "T2CEP" or "ACEP" using
the period-luminosity relations, which are different for the three different
types of Cepheids.
Note (2): Sub-classification of a T2CEP Cepheids into BL Herculis ("BL_HER"),
W Virginis ("W_VIR") or RV Tauris ("RV_TAU") sub-types depending on the source
periodicity.
Note (3): Best mode classification estimate:
"FUNDAMENTAL": fundamental mode for typeBestClassification="DCEP" or "ACEP"
"FIRST_OVERTONE": first overtone for typeBestClassification="DCEP" or "ACEP"
"SECOND_OVERTONE": second overtone for typeBestClassification="DCEP"
"MULTI": multi-mode pulsators for typeBestClassification="DCEP"
"UNDEFINED": if mode could not be clearly determined for
typeBestClassification="DCEP" or "ACEP"
"NOT_APPLICABLE": when typeBestClassification="T2CEP"
The Cepheid pulsation mode is assigned using the period-luminosity and
period-Wesenheit relations, which are different for the various pulsation modes
as well as analysing the Fourier parameters vs period plots.
The type "MULTI" is assigned to stars pulsating in two or more modes
simultaneously.
Note (4): Sub-classification of multi mode DCEP variables according to their
position in the "Petersen diagram" (see e.g. Fig. 1 in Soszynski et al.,
2015AcA....65..329S). F,1O,2O and 3O mean fundamental, first, second and third
overtone, respectively.
Byte-by-byte Description of file: rrlyrae.dat
Bytes Format Units Label Explanations
1- 4 A4 --- TBest Best type classification estimate
(best_classification) (1)
6- 23 I18 --- SolID Solution Identifier (solution_id) (G1)
25- 43 I19 --- Source Unique source identifier (source_id) (G2)
45- 56 F12.8 d Pf ? Period corresponding to the fundamental
pulsation mode (for multi mode pulsators) in
the G band time series (pf) (G5)
58- 67 F10.8 d e_Pf ? Uncertainty of the Pf period (pf_error) (G6)
69- 78 F10.8 d P1O ? Period corresponding to the first overtone
pulsation mode (for multi mode pulsators) in
the G band time series (p1_o) (G7)
80- 89 F10.8 d e_P1O ? Uncertainty of the P2O period
(p1oerror) (G6)
91-103 F13.8 d EpG Epoch of the maximum of the light curve in the
G band (JD=2455197.5) (epoch_g) (G10)
105-114 F10.8 d e_EpG Uncertainty on the epoch parameter epoch G
(epochgerror)
116-128 F13.8 d EpBP Epoch of the maximum of the light curve in the
BP band (JD=2455197.5) (epoch_bp) (G10)
130-139 F10.8 d e_EpBP Uncertainty on the epoch parameter epoch BP
(epochbperror)
141-153 F13.8 d EpRP Epoch of the maximum of the light curve in the
RP band (JD=2455197.5) (epoch_rp) (G10)
155-164 F10.8 d e_EpRP Uncertainty on the epoch parameter epoch RP
(epochrperror)
166-174 F9.6 mag Gmag Intensity-averaged magnitude in the G band
(intaverageg)
176-183 F8.6 mag e_Gmag Uncertainty on Intensity-averaged magnitude in
the G band (intaverageg_error) (G11)
185-193 F9.6 mag BPmag ? Intensity-averaged magnitude in the BP band
(intaveragebp)
195-202 F8.6 mag e_BPmag ? Uncertainty on Intensity-averaged magnitude
in the BP band (intaveragebp_error) (G11)
204-212 F9.6 mag RPmag ? Intensity-averaged magnitude in the RP band
(intaveragerp)
214-221 F8.6 mag e_RPmag ? Uncertainty on Intensity-averaged magnitude
in the RP band (intaveragerp_error) (G11)
223-230 F8.6 mag AmpG Peak-to-peak amplitude of the G band light
curve (peaktopeak_g) (G12)
232-239 F8.6 mag e_AmpG Uncertainty on the AmpG parameter
(peaktopeakgerror) (G13)
241-249 F9.6 mag AmpBP ? Peak-to-peak amplitude of the BP band light
curve (peaktopeak_bp) (G12)
251-258 F8.6 mag e_AmpBP ? Uncertainty on the AmpBP parameter
(peaktopeakbperror) (G13)
260-267 F8.6 mag AmpRP ? Peak-to-peak amplitude of the RP band light
curve (peaktopeak_rp) (G12)
269-277 F9.6 mag e_AmpRP ? Uncertainty on the AmpRP parameter
(peaktopeakrperror) (G13)
279-283 F5.2 [-] [Fe/H] ? Metallicity of the star from the Fourier
parameters of the light curve
(metallicity) (G14)
285-289 F5.2 [-] e_[Fe/H] ? Uncertainty of the metallicity parameter
(metallicity_error)
291-297 F7.5 --- R21G ? Fourier decomposition parameter r21G: A2/A1
(for G band) (r21_g) (G15)
299-305 F7.5 --- e_R21G ? Uncertainty on the r21G parameter: A2/A1
(for G band) (r21gerror) (G16)
307-313 F7.5 --- R31G ? Fourier decomposition parameter A3/A1
(for G band) (r31_g) (G15)
315-321 F7.5 --- e_R31G ? Uncertainty on the r31G parameter: A3/A1
(for G band) (r31gerror) (G16)
323-329 F7.5 rad phi21G ? Fourier decomposition parameter
phi21G: phi2-2*phi1 (for G band)
(phi21_g) (G17)
331-338 F8.5 rad e_phi21G ? Uncertainty on the phi21G parameter
(for G band) (phi21gerror) (G18)
340-346 F7.5 rad phi31G ? Fourier decomposition parameter
phi31G: phi3-3*phi1 (for G band)
(phi31_g) (G17)
348-354 F7.5 rad e_phi31G ? Uncertainty on the phi31G parameter
(for G band) (phi31gerror) (G18)
356-358 I3 --- o_EpG Number of G FoV epochs used in the fitting
algorithm (numcleanepochs_g)
360-362 I3 --- o_EpBP Number of BP epochs used in the fitting
algorithm (numcleanepochs_bp)
364-366 I3 --- o_EpRP Number of RP epochs used in the fitting
algorithm (numcleanepochs_rp)
368-372 F5.2 mag Gabs ? Interstellar absorption in the G-band
(g_absorption)
374-378 F5.2 mag e_Gabs ? Error on the interstellar absorption in the
G-band (gabsorptionerror)
Note (1): Classification of an RR Lyrae star according to the pulsation mode:
RRc ("RRC") for first overtone, RRab ("RRAB") for fundamental mode, and
RRd ("RRD") for double modes, obtained using the period-amplitude diagram in
the G-band; the plots of the Fourier parameters R21 and Phi2 vs period
and the Petersen diagram.
Byte-by-byte Description of file: lpv.dat
Bytes Format Units Label Explanations
1- 18 I18 --- SolID Solution Identifier (G1) (solution_id)
20- 38 I19 --- Source Unique source identifier (G2) (source_id)
40- 47 F8.4 mag MBOL [-23.1415/10.8172]? Absolute bolometric
magnitude of the star (absmagbol)
49- 58 F10.4 mag e_MBOL [0.0518/56681.7485]? Error of absolute
bolometric magnitude (absmagbol_error)
60 I1 --- Flag Red supergiant flag (marks stars that are
probably red supergiants) (rsg_flag)
62- 68 F7.4 mag BolCorr [-9.1792/-0.2194] Bolometric correction for
LPVs (bolometric_corr) (1)
70- 75 F6.4 mag e_BolCorr [0.005/5.9739] Error of the bolometric
correction (bolometriccorrerror) (2)
77- 84 F8.6 d-1 Freq [0.000011/0.016666] Frequency of the LPV
(frequency)
86- 94 F9.6 d-1 e_Freq [0.000027/65.899389] Error on the frequency
(frequency_error)
Note (1): This parameter gives the bolometric correction for the case of LPVs;
details of the calculation can be found in Chapter [chap:cu7var] of the
release documentation. For DR2, the bolometric correction was fixed to a
specific value in three cases. First for red supergiant LPVs, identified with,
the value was set to -0.71mag. Second, the value was set to -2.2mag for LPVs
with G amplitude variations >3mag, where the variability amplitude is computed
as the 5-95% trimmed range using the LEGACY strategy of commons-math to
compute the percentiles. Third, for all cases for which the uncertainty in
BP or in RP was larger than 4mag, the BP-RP color was assumed to be 3.25mag,
at which value the bolometric correction is -1.729mag.
Note (2): This parameter gives the error of the bolometric correction for the
case of LPVs. For DR2, the bolometric correction was fixed to a specific
value in three cases. First for red supergiant LPVs, identified with, the
value was set to 0.3mag. Second, the value was set to 0.005mag for LPVs
with G amplitude variations >3mag, where the variability amplitude is
computed as the 5-95% trimmed range using the LEGACY strategy of
commons-math to compute the percentiles. Third, for all cases for which
the uncertainty in BP or in RP was larger than 4mag, the BP-RP color was
assumed to be 3.25mag and the error on BP-RP assumed to be 2mag, at which
values the bolometric correction error is 1.892mag.
Byte-by-byte Description of file: varres.dat
Bytes Format Units Label Explanations
1- 18 I18 --- SolID Solution Identifier (meta.version) (G1)
20- 38 I19 --- Source Unique source identifier (source_id) (G2)
40- 51 A12 --- Classifier Name of the classifier used to produce this
result (classifier_name) (1)
53- 62 A10 --- BClass Name of best class, see table
VariClassifierDefinition for details of
the class (bestclassname) (2)
64- 70 F7.5 --- BClassScore [0/1] Score of the best class
(bestclassscore) (3)
Note (1): nTransits:2+ : Multi-stage Random Forest semi-supervised classifier
applied to time series with 2 or more field-of-view transits in the G band
(solID=369295546864633574)
Note (2): Best classes as follows:
ACEP = Anomalous Cepheids
ARRD = Anomalous double-mode RR Lyrae stars
CEP = Classical (delta) Cepheids
DSCT_SXPHE = Variable stars of types delta Scuti (DSCT) and
SX Phoenicis (SXPHE)
MIRA_SR = Long period variable stars including omicron Ceti (MIRA)
and semiregular (SR) variables
RRAB = Fundamental-mode RR Lyrae stars
RRC = First-overtone RR Lyrae stars
RRD = Double-mode RR Lyrae stars
T2CEP = Type-II Cepheids
Note (3): It describes a quantity between 0 and 1 which is related to the
confidence of the classifier in the identification of the best class
(classBestName) by a monotonically increasing function (depending on class).
Byte-by-byte Description of file: shortts.dat
Bytes Format Units Label Explanations
1- 18 I18 --- SolID Solution Identifier (solution_id) (G1)
20- 38 I19 --- Source Unique source identifier (source_id) (G2)
40- 47 F8.6 mag Amp Amplitude estimate of all per CCD G-band
photometry (quantile(95%)-quantile(5%))
(amplitude_estimate)
49- 51 I3 --- Nfov [14/109] Number of FoV transits with more than
7 CCD measurements after time series cleaning
(numberoffov_transits)
53- 60 F8.6 --- abbe Mean of per-FOV Abbe values derived from CCD
G-band photometry
(meanoffovabbevalues) (1)
62 I1 --- Nvario Number of points in the variogram
(variogramnumpoints)
64- 71 F8.6 d Tvario Characteristic time scales of variability
(variogramchartimescales)
73- 80 F8.6 mag+2 Vvario Variogram values associated with the
variogramCharTimescales (variogram_values)
82- 91 F10.6 d-1 Freq [1.006922/143.926266] Frequency search result
for either G CCD, G FoV, BP or RP photometry
(frequency) (2)
Note (1): This parameter is filled by the mean of per-FoV Abbe values derived
from per-CCD G-band photometry. Considering a given source, for each of its
FoV transits containing more than one per-CCD measurement, the associated
Abbe value from per-CCD G-band photometry is derived as
abbe =
{Sum}(mag(t{i+1})-mag(ti))^{2}/2{Sum}(mag(ti)-<mag(ti)>)^{2}
where <mag(ti)> is the mean of the per-CCD measurements of the transit.
The value of meanOfFovAbbeValues is calculated as the mean of these per-FoV
Abbe values.
Note (2): The parameter is filled by the frequency value resulting from the
period search (method LOMB_SCARGLE for DR2) performed either on the per-CCD
G-band photometry, per-FoV G-band photometry, BP photometry or RP photometry,
if periodicity has been detected. Otherwise it is set to NULL.
Byte-by-byte Description of file: tsstat.dat
Bytes Format Units Label Explanations
1- 18 I18 --- SolID Solution Identifier (G1) (solution_id)
20- 38 I19 --- Source Unique source identifier (G2) (source_id)
40- 42 I3 --- NGmag [5/242] Total number of G FOV transits
selected for variability analysis
(numselectedg_fov)
44- 56 F13.8 d TimeGmag Mean observation time for G FoV transits
(meanobstimegfov)
58- 69 F12.8 d DurGmag Time duration of the time series for G FoV
transits (timedurationg_fov)
71- 79 F9.6 mag b_Gmag Minimum G FoV magnitude (minmagg_fov)
81- 89 F9.6 mag B_Gmag Maximum G FoV magnitude (maxmagg_fov)
91- 99 F9.6 mag Gmag Mean G FoV magnitude (meanmagg_fov)
101-109 F9.6 mag GmagMed Median G FoV magnitude (medianmagg_fov)
111-119 F9.6 mag RangeGmag Difference between the highest and lowest G
FoV magnitudes (rangemagg_fov)
121-129 F9.6 mag stddevGmag Square root of the unweighted G FoV magnitude
variance (stddevmaggfov)
131-136 F6.3 --- SkeGmag Standardized unweighted G FoV magnitude
skewness (skewnessmagg_fov)
138-143 F6.3 --- KurGmag Standardized unweighted G FoV magnitude
kurtosis (kurtosismagg_fov)
145-152 F8.6 mag MADGmag Median Absolute Deviation (MAD) for G FoV
transits (madmagg_fov)
154-158 F5.3 --- AbbeGmag Abbe value for G FoV transits (abbemagg_fov)
160-168 F9.6 mag IQRGmag Interquartile range for G FoV transits
(iqrmagg_fov)
170-172 I3 --- NBPmag Total number of BP FOV transits selected for
variability analysis (numselectedbp)
174-186 F13.8 d TimeBPmag ? Mean observation time for BP FoV transits
(meanobstime_bp)
188-199 F12.8 d DurBPmag ? Time duration of the time series for BP FoV
transits (timedurationbp)
201-209 F9.6 mag b_BPmag ? Minimum BP FoV magnitude (minmagbp)
211-219 F9.6 mag B_BPmag ? Maximum BP FoV magnitude (maxmagbp)
221-229 F9.6 mag BPmag ? Mean BP FoV magnitude (meanmagbp)
231-239 F9.6 mag BPmagMed ? Median BP FoV magnitude (medianmagbp)
241-249 F9.6 mag RangeBPmag ? Difference between the highest and lowest BP
FoV magnitudes (rangemagbp)
251-259 F9.6 mag stddevBPmag ? Square root of the unweighted BP FoV
magnitude variance (stddevmag_bp)
261-267 F7.3 --- SkeBPmag ? Standardized unweighted BP FoV magnitude
skewness (skewnessmagbp)
269-275 F7.3 --- KurBPmag ? Standardized unweighted BP FoV magnitude
kurtosis (kurtosismagbp)
277-284 F8.6 mag MADBPmag ? Median Absolute Deviation (MAD) for BP FoV
transits (madmagbp)
286-290 F5.3 --- AbbeBPmag ? Abbe value for BP FoV transits (abbemagbp)
292-300 F9.6 mag IQRBPmag ? Interquartile range for BP FoV transits
(iqrmagbp)
302-304 I3 --- NRPmag ? Total number of RP FOV transits selected for
variability analysis (numselectedrp)
306-318 F13.8 d TimeRPmag ? Mean observation time for RP FoV transits
(meanobstime_rp)
320-331 F12.8 d DurRPmag ? Time duration of the time series for RP FoV
transits (timedurationrp)
333-341 F9.6 mag b_RPmag ? Minimum RP FoV magnitude (minmagrp)
343-351 F9.6 mag B_RPmag ? Maximum RP FoV magnitude (maxmagrp)
353-361 F9.6 mag RPmag ? Mean RP FoV magnitude (meanmagrp)
363-371 F9.6 mag RPmagMed ? Median RP FoV magnitude (medianmagrp)
373-381 F9.6 mag RangeRPmag ? Difference between the highest and lowest RP
FoV magnitudes (rangemagrp)
383-391 F9.6 mag stddevRPmag ? Square root of the unweighted RP FoV
magnitude variance (stddevmag_rp)
393-399 F7.3 --- SkeRPmag ? Standardized unweighted RP FoV magnitude
skewness (skewnessmagrp)
401-407 F7.3 --- KurRPmag ? Standardized unweighted RP FoV magnitude
kurtosis (kurtosismagrp)
409-416 F8.6 mag MADRPmag ? Median Absolute Deviation (MAD) for RP FoV
transits (madmagrp)
418-422 F5.3 --- AbbeRPmag ? Abbe value for RP FoV transits (abbemagrp)
424-432 F9.6 mag IQRRPmag ? Interquartile range for RP FoV transits
(iqrmagrp)
Byte-by-byte Description of file: numtrans.dat
Bytes Format Units Label Explanations
1- 19 I19 --- SolID Solution Identifier (solution_id) (G1)
21- 39 I19 --- Source Source Identifier (source_id) (G2)
41- 43 I3 --- Ntrans [5/277] Number of Gaia transits, in all bands,
in transits.dat file (n_transits)
Byte-by-byte Description of file: transits.dat
Bytes Format Units Label Explanations
1- 19 I19 --- Source Source Identifier (source_id) (G2)
21- 37 I17 --- TransitID Transit Identifier as defined in JP-011 and
received by DPCI from IDT (transit_id)
39- 51 F13.8 d TimeG ? Transit averaged G band observation time
(JD-2455197.5) (gtransittime) (1)
53- 69 E17.9 e-/s FG ? Transit averaged G band flux
(gtransitflux) (2)
71- 88 E18.9 e-/s e_FG ? Error on the transit averaged G band flux
(gtransitflux_error)
90-107 E18.9 --- RFG ? Transit averaged G band flux divided by its
error (gtransitfluxovererror)
109-117 F9.6 mag Gmag ? Transit averaged G band magnitude (converted
from transit averaged G band flux)
(gtransitmag)
119-127 F9.6 mag e_Gmag ? Error on transit averaged G band magnitude,
added by CDS (gtransitmag_error)
129-141 F13.8 d TimeBP ? BP CCD transit observation time
(JD-2455197.5) (bpobstime) (1)
143-159 E17.9 e-/s FBP ? BP band flux (bp_flux)
161-177 E17.9 e-/s e_FBP ? Error on the BP band flux (bpfluxerror)
179-195 E17.9 --- RFBP ? BP band flux divided by its error
(bpfluxover_error)
197-205 F9.6 mag BPmag ? BP band magnitude (converted from BP band
flux) (bp_mag)
207-219 E13.6 mag e_BPmag ? Error on the BP band magnitude, added by CDS
(bpmagerror)
221-233 F13.8 d TimeRP ? RP CCD transit observation time
(JD-2455197.5) (rpobstime) (1)
235-251 E17.9 e-/s FRP ? RP band flux (rp_flux)
253-269 E17.9 e-/s e_FRP ? Error on the RP band flux (rpfluxerror)
271-287 E17.9 --- RFRP ? RP band flux divided by its error
(rpfluxover_error)
289-297 F9.6 mag RPmag ? RP band magnitude (converted from RP band
flux) (rp_mag)
299-309 E11.6 mag e_RPmag ? Error on the RP band magnitude, added by CDS
(rpmagerror)
311 I1 --- noisy [0/1] G band flux scatter larger than expected
by photometry processing (all CCDs
considered) (photometryflagnoisy_data)
313 I1 --- smu [0/1] SM transit unavailable by photometry
processing (photometryflagsm_unavailable)
315 I1 --- af1u [0/1] AF1 transit unavailable by photometry
processing (photometryflagaf1_unavailable)
317 I1 --- af2u [0/1] AF2 transit unavailable by photometry
processing (photometryflagaf2_unavailable)
319 I1 --- af3u [0/1] AF3 transit unavailable by photometry
processing (photometryflagaf3_unavailable)
321 I1 --- af4u [0/1] AF4 transit unavailable by photometry
processing (photometryflagaf4_unavailable)
323 I1 --- af5u [0/1] AF5 transit unavailable by photometry
processing (photometryflagaf5_unavailable)
325 I1 --- af6u [0/1] AF6 transit unavailable by photometry
processing (photometryflagaf6_unavailable)
327 I1 --- af7u [0/1] AF7 transit unavailable by photometry
processing (photometryflagaf7_unavailable)
329 I1 --- af8u [0/1] AF8 transit unavailable by photometry
processing (photometryflagaf8_unavailable)
331 I1 --- af9u [0/1] AF9 transit unavailable by photometry
processing (photometryflagaf9_unavailable)
333 I1 --- bpu [0/1]? ABP transit unavailable by photometry
processing (photometryflagbp_unavailable)
335 I1 --- rpu [0/1]? ABP transit unavailable by photometry
processing (photometryflagrp_unavailable)
337 I1 --- smr [0/1] SM transit rejected by photometry
processing(photometryflagsm_reject)
339 I1 --- af1r [0/1] AF1 transit rejected by photometry
processing (photometryflagaf1_reject)
341 I1 --- af2r [0/1] AF2 transit rejected by photometry
processing (photometryflagaf2_reject)
343 I1 --- af3r [0/1] AF3 transit rejected by photometry
processing (photometryflagaf3_reject)
345 I1 --- af4r [0/1] AF4 transit rejected by photometry
processing (photometryflagaf4_reject)
347 I1 --- af5r [0/1] AF5 transit rejected by photometry
processing (photometryflagaf5_reject)
349 I1 --- af6r [0/1] AF6 transit rejected by photometry
processing (photometryflagaf6_reject)
351 I1 --- af7r [0/1] AF7 transit rejected by photometry
processing (photometryflagaf7_reject)
353 I1 --- af8r [0/1] AF8 transit rejected by photometry
processing (photometryflagaf8_reject)
355 I1 --- af9r [0/1] AF9 transit rejected by photometry
processing (photometryflagaf9_reject)
357 I1 --- bpr [0/1]? BP transit rejected by photometry
processing (photometryflagbp_reject)
359 I1 --- rpr [0/1]? RP transit rejected by photometry
processing (photometryflagrp_reject)
361 I1 --- VarGr [0/1]? Average G transit photometry rejected
by variability processing
(variabilityflagg_reject) (3)
363 I1 --- VarBPr [0/1]? Average BP transit photometry rejected
by variability processing
(variabilityflagbp_reject) (3)
365 I1 --- VarRPr [0/1]? Average RP transit photometry rejected
by variability processing
(variabilityflagrp_reject) (3)
Note (1): Field-of-view transit averaged observation time in units of
Barycentric JD (in TCB) in days -2455197.5, computed as follows.
First the observation time is converted from On-board Mission Time (OBMT) into
Julian date in TCB (Temps Coordonnee Barycentrique). Next a correction is
applied for the light-travel time to the Solar system barycentre, resulting in
Barycentric Julian Date (BJD). Finally, an offset of 2455197.5 days is applied
(corresponding to a reference time T0 at 2010-01-01T00:00:00) to have a
conveniently small numerical value.
Units: (Barycentric JD in TCB - 2455197.5 (day)).
For TimeG: Although the centroiding time accuracy of the individual CCD
observations is (much) below 1ms, this per-FoV observation time is averaged
over typically 9 CCD observations taken in a time range of about 44 sec.
Note (2): The average G flux value for the FoV transit. The calculation only
uses accepted transits. This could include SM and AF fluxes.
Note (3): Flag as follows:
1 = rejected
0 = processed
Byte-by-byte Description of file: rm.dat
Bytes Format Units Label Explanations
1- 12 F12.9 d ProtB Best rotation period (bestrotationperiod) (1)
14- 24 F11.9 d e_ProtB Error on best rotation period
(bestrotationperiod_error)
26- 32 F7.5 mag AImax Activity Index in segment
(maxactivityindex) (2)
34- 40 F7.5 mag e_AImax Error on Activity index in segment
(maxactivityindex_error) (3)
42- 49 F8.5 mag Gunsp The unspotted G magnitude in segment
(g_unspotted) (4)
51- 57 F7.5 mag e_Gunsp The unspotted G mag uncertainties in segment
(gunspottederror)
59- 66 F8.5 mag BPunsp ? The unspotted BP magnitude in segment
(bp_unspotted)
68- 74 F7.5 mag e_BPunsp ? The unspotted BP magnitude uncertainty in
segment (bpunspottederror)
76- 83 F8.5 mag RPunsp ? The unspotted RP magnitude in segment
(rp_unspotted)
85- 91 F7.5 mag e_RPunsp ? The unspotted RP magnitude uncertainty in
segment (rpunspottederror)
93-111 I19 --- SolID Solution Identifier (solution_idR) (G1)
113-131 I19 --- Source Source Identifier (source_id) (G2)
133-134 I2 --- Nseg Number of segments (num_segments) (5)
136-137 I2 --- Nout Number of outliers (num_outliers) (6)
Note (1): this field is an estimate of the stellar rotation period and is
obtained by averaging the periods obtained in the different segments
Note (2): this array stores the activity indexes measured in the different
segments. In a given segment the amplitude of variability A is taken as an
index of the magnetic activity level. The amplitude of variability is
measured by means of the equation: A=mag95-mag5 where mag95 and mag5 are the
95-th and the 5-th percentiles of the G-band magnitude values.
Note (3): error associated with the activity indexes in the G band. In a given
segment the error on the activity index A is computed by means of the equation:
sigmaA=sqrt{sigmamag952 + sigmamag52} where
sigmamag95 and sigmamag5 are the uncertainties of the measurements
associated with the 95th and 5th percentiles of the G-band magnitude values,
respectively
Note (4): in a given segment the G magnitude corresponding to the unspotted
state is estimated by taking the minimum G value in the segment.
Note (5): This is the number of time intervals (segments) in which the magnitude
and colour time-series are splitted. The segmentation of time-series is needed
because the spots due to the stellar magnetic activity have a life-time shorter
than the whole Gaia time-series. The rotational modulation induced by spots
can therefore be detected only in segments whose duration is comparable with
the spots life-time
Note (6): the number of outliers detected by the robust linear regression
procedure.
Byte-by-byte Description of file: rmseg.dat
Bytes Format Units Label Explanations
1- 19 I19 --- Source Unique source identifier (source_id) (G2)
21- 36 F16.12 d SProt ? Rotation period in segment
(segmentsrotationperiod) (1)
38- 54 E17.12 d e_SProt ? Rotation period uncertainty in segment
(segmentsrotationperiod_error)
56- 72 E17.12 % FAPsPRot FAP on rotation period in segment
(segmentsrotationperiod_fap) (2)
74- 82 F9.6 mag Scos ? Coefficient of cosine term of linear fit in
segment (segmentscosterm) (3)
84- 91 F8.6 mag e_Scos ? Error on cosin term (segmentscosterm_error)
93-101 F9.6 mag Ssin ? Coefficient of sin term of linear fit in
segment (segmentssinterm) (3)
103-110 F8.6 mag e_Ssin ? Error on sine term (segmentssinterm_error)
112-120 F9.6 mag Sa0 ? Constant term (A0) of linear fit in segment
(segmentsa0term) (3)
122-129 F8.6 mag e_Sa0 ? Error on constant term
(segmentsa0term_error)
131-137 F7.5 mag SAI Activity Index in segment
(segmentsactivityindex) (4)
139-145 F7.5 mag e_SAI Error on Activity index in segment
(segmentsactivityindex_error) (5)
147-154 F8.5 mag SGunsp The unspotted G magnitude in segment
(segmentsgunspotted)
156-162 F7.5 mag e_SGunsp The unspotted G magnitude uncertainty in
segment (segmentsgunspotted_error)
164-171 F8.5 mag SBPunsp ? The unspotted BP magnitude in segment
(segmentsbpunspotted)
173-179 F7.5 mag e_SBPunsp ? The unspotted BP magnitude uncertainty in
segment (segmentsbpunspotted_error)
181-188 F8.5 mag SRPunsp ? The unspotted RP magnitude in segment
(segmentsrpunspotted)
190-196 F7.5 mag e_SRPunsp ? The unspotted RP magnitude uncertainty in
segment (segmentsrpunspotted_error)
198-210 F13.8 d STimeS Time at which segments start (JD-2455197.5)
(segmentsstarttime) (6)
212-224 F13.8 d STimeE Time at which segments end (JD-2455197.5)
(segmentsendtime) (6)
226-234 F9.3 --- ScolI Colour-Magnitude Intercept in segment
(segmentscolourmag_intercept) (7)
236-242 F7.3 --- e_ScolI Colour-Magnitude Intercept uncertainty in
segment (segmentscolourmagintercepterror)
244-251 F8.4 --- ScolM Colour-Magnitude Slope in segments
(segmentscolourmag_slope) (7)
253-259 F7.4 --- e_ScolM Colour-Magnitude Slope uncertainty in segment
(segmentscolourmagslopeerror)
261-268 F8.5 --- Scor Correlation coefficient in segment
(segmentscorrelationcoefficient) (8)
270-276 F7.5 --- Ssigni Correlation coefficient significance in
segment (segmentscorrelationsignificance) (9)
Note (1): A period search algorithm is applied to the different time-series
segments. If the star is a solar-like variable the detected period is a measure
of the stellar rotation period. This array is filled with the periods detected
in the different segments (for each segment the period with the highest
statistical significance is stored).
Note (2): False Alarm Probability = Probability that that a white noise sequence
produces a peak similar or higher than the computed one; i.e.;
small FAP = little probability of noise;high FAP = noise is an acceptable
explanation for the peak.
Note (3): if a significative period T0 is detected in a time-series segment;
then the points of the time-series segment are fitted with the function
mag(t)=mag0+Acos(2{pi}/T0t) + Bsin(2{pi}/T0t).
This array stores the A terms obtained by the fitting procedure in the
different segments.
Note (4): this array stores the activity indexes measured in the different
segments. In a given segment the amplitude of variability A is taken as an
index of the magnetic activity level. The amplitude of variability is measured
by means of the equation: A=mag95-mag5 where mag95 and mag5 are the 95-th and
the 5-th percentiles of the G-band magnitude values.
Note (5): this array stores the errors associated with the activity indexes in
the G band. In a given segment the error on the activity index A is computed by
means of the equation: sigmaA=sqrt{sigmamag952+sigmamag52} where
sigmamag95and sigmamag5 are the uncertainties of the measurements
associated with the 95th and 5th percentiles of the G-band magnitude values,
respectively.
Note (6): an array filled with the starting (ending) times of segments in
Barycentric JD in TCB - 2455197.5 unit.
Note (7): a robust linear regression is applied to the points (BP-RP;G) in each
segment. This array is filled with the intercepts given by the fitting
procedure in the different segments.
Note (8): The Pearson correlation coefficient r between BP-RP and G is computed
in each segment. The higher is the Pearson coefficient the higher is the
probability that the stellar variability is due to rotational modulation. This
array is filled with the Pearson coefficients obtained in the different
segments.
Note (9): this array is filled with the statistical significances associated
with the Pearson coefficients computed in the different segments. The
significance p associated with a given r=r0 gives the probability P(r>=r0)
that two sets of uncorrelated measurements have a Pearson coefficient >=r0.
Byte-by-byte Description of file: rmout.dat
Bytes Format Units Label Explanations
1- 19 I19 --- Source Unique source identifier (source_id) (G2)
21- 33 F13.8 d TimeOutliers Times at which outliers occurs
(JD-2455197.5 ) (outliers_time) (1)
Note (1): times at which the detected outliers occurred in Barycentric JD in
TCB-2455197.5 unit.
Byte-by-byte Description of file: ssoobj.dat
Bytes Format Units Label Explanations
1- 19 I19 --- SolID Solution Identifier (solution_id) (G1)
21- 31 I11 --- Source Unique source identifier (source_id) (G3)
33- 35 I3 --- Nobs [15/591] Number of CCD-level observations of
the asteroid that appear in the
SsoObservation (ssoobs.dat) table (numofobs)
37- 42 I6 --- MPC Minor planet number attributed by MPC
(number_mp)
44- 59 A16 --- Name MPC name or preliminary designation
(denomination)
Byte-by-byte Description of file: ssoorb.dat
Bytes Format Units Label Explanations
1- 19 I19 --- SolID Solution Identifier (solution_id) (G1)
21- 26 I6 --- MPC Asteroid number assigned by MPC
(number_mp)
28- 43 A16 --- Name MPC name or preliminary designation
(designation)
45- 49 F5.2 mag Hmag Absolute magnitude H for the asteroid
(mag_h) (2)
51- 54 F4.2 --- Slopeg Slope parameter of the magnitude-phase law
(slope_g)
56- 62 I7 --- Code Object specific flags (code) (3)
64- 68 I5 d Obs.arc Time interval of the observations used to
compute the orbit (obs_arc)
70- 73 I4 --- Obs.num Number of observations used to compute the
orbit (obs_num)
75- 82 A8 "YYYYMMDD" Obs.epoch Epoch of osculation, yyyymmdd (TDT)
(osc_epoch) (4)
84- 93 F10.6 deg Orb.m Orbital element: Mean anomaly (orb_m)
95-104 F10.6 deg Omega Argument of perihelion at equinox J2000.0
(omega) (5)
106-115 F10.6 deg Node.omega Longitude of the ascending node at equinox
J2000.0 (node_omega) (5)
117-125 F9.6 deg Incl Orbit inclination (J2000.0) (inclination)
127-136 F10.8 --- Eccen Orbit eccentricity (eccentricity)
138-148 F11.8 AU a Semimajor axis of the orbit (a)
150-157 A8 "YYYYMMDD" Orb.Date Date of orbit computation
(MST, = UTC - 7 hr) (orb_date)
159-164 F6.4 arcsec CEU Absolute value of the current 1-sigma
ephemeris uncertainty (ceu)
166-172 F7.4 mas/s CEU.rate Rate of change of the orbit uncertainty
(ceu_rate) (6)
174-181 A8 "YYYYMMDD" CEU.epoch Date of CEU (0 hr UT) (ceu_epoch)
Note (2): Number of decimal places depending on accuracy (zero to 2), except for
unnumbered asteroids (2 decimals even if H is poorly known)
Note (3): See ftp://cdsarc.u-strasbg.fr/pub/cats/B/astorb/astorb.html for
a full description
Note (4): The epoch is the Julian date ending in 00.5 nearest the date the
orbit data set was compiled.
Note (5): Note this is not ICRS because these orbits are heliocentric and all
angles are referred to the nodal point defined at equinox J2000.0)
Note (6): Note that in astorb it is given in arcsec/day.
Byte-by-byte Description of file: ssores.dat
Bytes Format Units Label Explanations
1- 11 I11 --- Source Unique source identifier (source_id) (G3)
13- 29 I17 --- Transit Transit Identifier (transit_id) (2)
31- 48 I18 --- Obs.ID Observation Identifier (observation_id) (3)
50- 55 I6 --- MPC Minor Planet number attributed by MPC
(number_mp)
57- 74 F18.13 d Epoch Gaiacentric epoch TCB(Gaia) (epoch) (G4)
76- 94 E19.13 mas Res.RA Post-orbital fit residual in RA*cos(DE)
direction (residual_ra)
96-114 E19.13 mas Res.DE Post-orbital fit residual in DE direction
(residual_dec)
116-133 E18.13 mas Res.AL Post-orbital fit residual in AL (Along Scan)
direction (residual_al)
135-153 E19.13 mas Res.AC Post-orbital fit residual in AC (Across Scan)
(residual_ac)
155 I1 --- Select [0/1] Flag for observation not rejected by
orbital fit (selected) (5)
Note (2): The Transit Id is a number obtained from the combination of data
fields from the telemetry. More specifically, from AF1 refacquisitiontime,
AF1 ac, FOV and CCD Row. It uniquely identifies the transit of a source on
the focal plane.
Note (3): Identifier at single CCD level of the observation of a Solar System
object. It is unique, and obtained from a combination of transitId and an
integer number representing the CCD strip.
Note (5): Post-fit residuals are then computed. Rejection of single
observations may occur in this process.
This flag is 1 when no observation is rejected.
Byte-by-byte Description of file: ssoobs.dat
Bytes Format Units Label Explanations
1- 19 I19 --- SolID Solution Identifier (solution_id) (G1)
21- 31 I11 --- Source Unique source identifier (source_id) (G3)
33- 50 I18 --- Obs.Id Observation Identifier (observation_id)
52- 57 I6 --- MPC Minor Planet number attributed by MPC
(number_mp)
59- 76 F18.13 d Epoch Gaiacentric epoch TCB(Gaia) (JD-2455197.5)
(epoch) (G4)
78- 86 E9.3 d e_Epoch Error in Gaiacentric epoch
(for both Epoch and EpochUTC) (epoch_err)
88-105 F18.13 d EpochUTC Gaiacentric epoch UTC (epoch_utc)
(JD-2455197.5) (1)
107-129 F23.19 deg RAdeg ICRS Right Ascension of the source as
observed by Gaia at epoch EpochUTC (ra)
133-155 E23.19 deg DEdeg ICRS Declination of the source as observed
by Gaia at epoch EpochUTC (dec)
157-163 F7.4 mas e_RAdeg Standard error of right ascension - systematic
component (e_RA*cosDE) (raerrorsystematic)
165-171 F7.4 mas e_DEdeg Standard error of declination - systematic
component (decerrorsystematic)
173-179 F7.4 --- RADEcors Correlation of RA and DE errors - systematic
component (radeccorrelation_systematic )
181-188 F8.4 mas eRAdeg Standard error of right ascension - random
component (e_RA*cosDE) (raerrorrandom)
190-197 F8.4 mas eDEdeg Standard error of declination - random
component (decerrorrandom)
199-205 F7.4 --- RADEcorr Correlation of RA and DE errors - random
component (radeccorrelation_random)
207-215 F9.6 mag Gmag ? Calibrated G magnitude (corrected G
magnitude based on refined signal
analysis) (g_mag)
217-234 E18.14 e-/s FG ? Average calibrated G flux for the
transit (g_flux)
236-253 E18.14 e-/s e_FG ? Error on the G flux (gfluxerror)
255-276 E22.17 AU Xpos Barycentric equatorial J2000 (ICRS)
x position of Gaia at the epoch of
observation (x_gaia)
278-299 E22.17 AU Ypos Barycentric equatorial J2000 (ICRS)
y position of Gaia at the epoch of
observation (y_gaia)
301-322 E22.17 AU Zpos Barycentric equatorial J2000 (ICRS)
z position of Gaia at the epoch of
observation (z_gaia)
324-345 E22.17 AU/d VX Barycentric equatorial J2000 (ICRS)
x velocity of Gaia at the epoch of
observation (vx_gaia)
347-368 E22.17 AU/d VY Barycentric equatorial J2000 (ICRS)
y velocity of Gaia at the epoch of
observation (vy_gaia)
370-391 E22.17 AU/d VZ Barycentric equatorial J2000 (ICRS)
z velocity of Gaia at the epoch of
observation (vz_gaia)
393-402 F10.6 deg PA Position angle of the scanning direction
(positionanglescan) (2)
404 I1 % ConfLevel [0] Level of confidence of the
identification (levelofconfidence) (3)
Note (1): Gaiacentric epoch in UTC in JD-2455197.5 corresponding to
right ascension and declination.
Note (2): Position angle of the scan direction at the epoch of observation in
the equatorial reference frame.
0 = North direction, pi/2 = increasing right ascension, pi = South,
3pi/2 = decreasing right ascension.
It is defined as the angle between the AL direction and the direction to the
North Pole, at the SSO position, after applying the correction for aberration.
As a consequence of this correction for aberration, the AC direction is no
longer strictly perpendicular to the AL direction.
Note (3): Level of confidence in the identification of the given SSO source_id
with this observation as follows:
0 = completely unambiguous
100 = no identification
Global notes:
Note (G1): All Gaia data processed by the Data Processing and Analysis
Consortium comes tagged with a solution identifier. This is a numeric field
attached to each table row that can be used to unequivocally identify the
version of all the subsystems that where used in the generation of the data as
well as the input data used. It is mainly for internal DPAC use but is included
in the published data releases to enable end users to examine the provenance of
processed data products. To decode a given solution ID visit.
https://gaia.esac.esa.int/decoder/decoder.jsp
Note (G2): Unique source identifier (unique within a particular Data Release)
Long Description: A unique numerical identifier of the source, encoding the
approximate position of the source (roughly to the nearest arcmin), the
provenance (data processing centre where it was created), a running number,
and a component number.
The approximate equatorial (ICRS) position is encoded using the nested HEALPix
scheme at level 12 (Nside = 4096), which divides the sky into ~200 million
pixels of about 0.7 arcmin2.
The source ID consists of a 64-bit integer, least significant bit = 1 and most
significant bit = 64, comprising:
- a HEALPix index number (sky pixel) in bits 36 - 63; by definition the
smallest HEALPix index number is zero.
- a 3-bit Data Processing Centre code in bits33 - 35; for example
MOD(sourceId / 4294967296, 8) can be used to distinguish between sources
initialised via the Initial Gaia Source List by the Torino DPC (code = 0)
and sources otherwise detected and assigned by Gaia observations (code>0)
- a 25-bitplus 7 bit sequence number within the HEALPix pixel in bits 1-32
split into:
- a 25 bitrunning number in bits 8-32; the running numbers are defined to be
positive, i.e. never zero
- a 7-bit component number in bits 1- 7
This means that the HEALpix index leel 12 of a given source is contained in
the most significant bits. HEALpix index of 12 and lower levels can thus be
retrieved as follows:
- HEALpix level 12 = source_id / 34359738368
- HEALpix level 11 = source_id / 137438953472
- HEALpix level 10 = source_id / 549755813888
- HEALpix level n = source_id / 235*4(12-level)
Additional details can be found in the Gaia DPAC public document _Source
Identifiers - Assignment and Usage throughout DPAC_
(document code GAIA-C3-TN-ARI-BAS-020).
Note (G3): A unique single numerical identifier of the source obtained from
GaiaSource (for a detailed description see GaiaSource.sourceId).
Note in particular that these identifiers are by convention negative for SSOs.
Note (G4): Gaiacentric epoch TCB(Gaia) in JD corresponding to the time of
crossing of the fiducial line of the CCD. This is the epoch to which the
target coordinates and the position/velocity of Gaia are referred to.
To avoid loss of precision the reference time J2010.0 is subtracted.
Barycentric JD in TCB - 2455197.5.
Note (G5): for single-mode pulsators classified as fundamental mode pulsators,
this parameter is filled with the periodicity found in the time-series.
For double-mode RR Lyrae this parameter is filled with the period corresponding
to the longer periodicity. For double-mode DCEPs this parameter is filled with
the period corresponding to the longer periodicity if the DCEP is classified
as "F/1O" or "F/2O". For triple-mode DCEPs this parameter is filled with the
period corresponding to the longer periodicity if the DCEP is classified as
"F/1O/2O" This value is obtained by modelling the G band time series using the
Levenberg-Marquardt non linear fitting algorithm (see Clementini et al.,
2016A&A...595A.133C, Cat. I/337).
Note (G6): This parameter is filled with the uncertainty of the period
parameter. Its value is derived from Monte Carlo simulations that generate
several (100) time series with the same time path as the data points but with
magnitudes generated randomly around the corresponding data values. For each of
these time series the period is computed. The mean of all the periods and its
standard deviation are then derived, and the latter value is used to fill the
periodError parameter. The value refers to the analysis performed on the
G band time series.
Note (G7): for single-mode pulsators classified as first-overtone pulsators,
this parameter is filled with the periodicity found in the time-series.
For double-mode RR Lyrae this parameter is filled with the period corresponding
to the shortest periodicity. For double-mode DCEPs this parameter is filled
with the period corresponding to the shortest periodicity if the DCEP is
classified as "F/1O"; otherwise it is filled with the longest one if the
classification is "1O/2O" or "1O/3O". For triple-mode DCEPs this parameter is
filled with the period corresponding to the intermediate periodicity if the
DCEP is classified as "F/1O/2O"; it is filled with the longest periodicity if
the classification is "1O/2O/3O". This value is obtained by modelling the G
time series using the Levenberg-Marquardt non linear fitting algorithm
(see Clementini et al., 2016A&A...595A.133C, Cat. I/337)
Note (G8): For single-mode DCEPs classified as second-overtone pulsators, this
parameter is filled with the periodicity found in the time-series. For
double-mode DCEPs this parameter is filled with the period corresponding to
the shortest periodicity if the DCEP is classified as "1O/2O" of "F/2O";
otherwise it is filled with the longest periodicity if the classification
is "2O/3O". For triple-mode DCEPs this parameter is filled with the period
corresponding to the shortest periodicity if the DCEP is classified as
"F/1O/2O"; it is filled with the intermediate periodicity if the classification
is "1O/2O/3O". This value is obtained by modelling the G time series using the
Levenberg-Marquardt non linear fitting algorithm
(see Clementini et al., 2016A&A...595A.133C, Cat. I/337).
Note (G9): for double-mode DCEPs this parameter is filled with the periodicity
found in the time-series corresponding to the shortest periodicity if the DCEP
is classified as "1O/3O" of "2O/3O". For triple-mode DCEPs this parameter is
filled with the period corresponding to the shortest periodicity if the DCEP is
classified as "1O/2O/3O". This value is obtained by modelling the G time series
using the Levenberg-Marquardt non linear fitting algorithm
(see Clementini et al., 2016A&A...595A.133C, Cat. I/337).
Note (G10): Epoch of maximum light for the Gaia G band light curve. It
corresponds to the Baricentric Julian day (BJD) of the maximum value of the
light curve model which is closest to the BJD of the first observations
-3 times the period of the source (first periodicity depending on the
pulsation mode).
The mentioned BJD is offset by JD 2455197.5 (= J2010.0)
(Barycentric JD in TCB - 2455197.5 (day)).
Note (G11): This parameter is filled with the uncertainty of the
Average_magnitude parameter. Its value is derived from Monte Carlo simulations
that generate several (100) time series with the same time path as the data
points but with magnitudes generated randomly around the corresponding data
values. For each of these time series the Average_magnitude is computed.
The mean of all the magnitudes found and its standard deviation are then
computed, and the latter value is kept to fill the
AveragemagnitudeError parameter.
Note (G12): This parameter is filled with the peak-to-peak amplitude value of
the band light curve. The peak-to-peak amplitude is calculated as the
(maximum)-(minimum) of the modelled folded light curve in the band. The light
curve of the target star is modelled with a truncated Fourier series
(mag(tj)=zp+{SIGMA}[Aisin(ix2{pi}{nu}maxtj+{phi}i)]). Zero-point (zp),
period (1/{nu}max), number of harmonics (i), amplitudes (Ai), and
phases ({phi}i) of the harmonics, for the band light curve are determined using
the Levenberg-Marquardt non linear fitting algorithm.
Note (G13): This parameter is filled with the uncertainty value of the Amplitude
parameter. Its value is derived from Monte Carlo simulations that generate
several (100) time series with the same time path as the data points but with
magnitudes generated randomly around the corresponding data values. For each of
these time series the peakToPeakG is computed. The mean of all the amplitudes
found and its standard deviation are then computed, and the latter value is
kept to fill the Amplitude_Error parameter.
Note (G14): this parameter is filled with the [Fe/H] metallicity derived for the
source from the Fourier parameters of the G-band light curve.
Note (G15): this parameter is filled with the Fourier decomposition parameter
R21=A2/A1 (R31=A3/A_1), where A2 is the amplitude of the 2nd
harmonic, A3 is the amplitude of the 3rd harmonic and A1 is the amplitude
of the fundamental harmonic of the truncated Fourier series defined as
(mag(tj)=zp+{SIGMA}[Aisin(ix2{Pi}{nu}maxtj+{phi}i)]) used to model the G-band
light curve. Zero-point (zp), period (1/{nu}max), number of harmonics (i),
amplitudes (Ai), and phases ({phi}i) of the harmonics, are determined using the
Levenberg-Marquardt non linear fitting algorithm.
Note (G16): this parameter is filled with the uncertainty value on the r21G/r31G
parameter. Its value is derived from Monte Carlo simulations that generate
several (100) time series with the same time path as the data points but with
magnitudes generated randomly around the corresponding data values. For each of
these time series the r21G/r31G is computed. The mean of all the r21G/r31G
values found and its standard deviation are then computed, and the latter
value is kept to fill the r21G/r31GError parameter.
Note (G17): this parameter is filled with the Fourier decomposition parameter
{phi}21={phi}2-2{phi}1 ({phi}31={phi}3-3{phi}1): where {phi}2 is the phase
of the 2nd harmonic, {phi}3 is the phase of the 3rd harmonic and {phi}1 is the
phase of the fundamental harmonic of the truncated Fourier series defined as
(mag(tj)=zp+{SIGMA}[Aisin(ix2{pi}{nu}maxtj+{phi}i)]) used to model the G-band
light curve. Zero-point (zp), period (1/{nu}max), number of harmonics (i),
amplitudes (Ai), and phases ({phi}i) of the harmonics, are determined using the
Levenberg-Marquardt non linear fitting algorithm.
Note (G18): this parameter is filled with the uncertainty of the phi21G (phi31G)
parameter. Its value is derived from Monte Carlo simulations that generate
several (100) time series with the same time path as the data points but with
magnitudes generated randomly around the corresponding data values. For each of
these time series the phi21G (phi31G) is computed. The mean of all the
phi21G ((phi31G) values is found and its standard deviation are then computed,
and the latter value is kept to fill the phi21G((phi31G)Error parameter.
History:
From Gaia team
Acknowledgements:
For radial velocity catalog:
Caroline Soubiran, caroline.soubiran(at)u-bordeaux.fr,
[Lab. d'Astrophys. Bordeaux]
For all other catalogs:
Gaia team
References:
Gaia Data Release 2: Summary of the contents and survey properties,
Gaia Collaboration, Brown, A.G.A., et al. (2018A&A...616A...1G)
Gaia Data Release 2: The astrometric solution,
Lindegren, L., et al. (2018A&A...616A...2L)
Gaia Data Release 2: Calibration and mitigation of electronic offset effects
in Gaia data, Hambly, N., et al. (2018A&A...616A..15G)
Gaia Data Release 2: Processing of the photometric data,
Riello, M., et al. (2018A&A...616A...3R)
Gaia Data Release 2: The photometric content and validation,
Evans, D.W., et al. (2018A&A...616A...4E)
Gaia Data Release 2: The Gaia Radial Velocity Spectrometer,
Cropper, M., et al. (2018A&A...616A...5C)
Gaia Data Release 2: The catalogue of radial velocity standard stars
Soubiran, C., et al. (2018A&A...616A...7S)
Gaia Data Release 2: Processing, validation and performance of the
spectroscopic data, Sartoretti, P., et al. (2018A&A...616A...6S)
Gaia Data Release 2: Properties and validation of the radial velocities,
Katz, D., et al. (2018A&A..in.prep...)
Gaia Data Release 2: Summary of variability processing and analysis results,
Holl, B., et al. (2018A&A..in.prep...)
Gaia Data Release 2: First stellar parameters from Apsis,
Andrae, R., et al. (2018A&A...616A...8A)
Gaia Data Release 2: Catalogue validation,
Arenou, F., et al. (2018A&A...616A..17A)
Gaia Data Release 2: Cross-match with external catalogues: algorithm and
statistics, Marrese, P.M., et al. (2018A&A..in.prep...)
Gaia Data Release 2: On the use of Gaia parallaxes,
Luri, X., et al. (2018A&A...616A...9L)
Gaia Data Release 2: The celestial reference frame (Gaia-CRF2),
Gaia Collaboration, Mignard, F., et al. (2018A&A...616A..14G)
Gaia Data Release 2: Observational Hertzsprung-Russell diagrams,
Gaia Collaboration, Babusiaux, C., et al. (2018A&A...616A..10G),
Cat. J/A+A/616/A10
Gaia Data Release 2: Observations of Solar System objects,
Gaia Collaboration, Spoto, F., et al. (2018A&A...616A..13G)
Gaia Data Release 2: Mapping the Milky Way disk kinematics,
Gaia Collaboration, Katz, D., et al. (2018A&A...616A..11G)
Gaia Data Release 2: The kinematics of globular clusters and dwarf galaxies
around the Milky Way, Gaia Collaboration, Helmi, A., et al.
(2018A&A...616A..12G), Cat. J/A+A/616/A12
Gaia Data Release 2: Variable stars in the Colour-Magnitude Diagram,
Gaia Collaboration, Eyer, L., et al. (2018A&A..in.prep...)
Gaia Data Release 2 - Rotational modulation in late-type dwarfs,
Lanzafame, A.C, et al. (2018A&A...616A..16L)
================================================================================
(End) Arnaud Siebert, Thomas Boch, Patricia Vannier [CDS] 25-Apr-2018