ACDS V10.0 - Sat Apr 27 06:40:53 CEST 2019
|  | Detailed Description of VII/279 :
 SDSS quasar catalog: twelfth data release (Paris+, 2017)
 |  | 
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.
VII/279          SDSS quasar catalog: twelfth data release   (Paris+, 2017)
================================================================================
The Sloan Digital Sky Survey Quasar Catalog: Twelfth data release.
    Paris I., Petitjean P., Ross N.P., Myers A.D., Aubourg E., Streblyanska A.,
    Bailey S., Armengaud E., Palanque-Delabrouille N., Yeche C., Hamann F.,
    Strauss M.A., Albareti F.D., Bovy J., Bizyaev D., Brandt W.N., Brusa M.,
    Buchner J., Comparat J., Croft R.A.C., Dwelly T., Fan X., Font-Ribera A.,
    Ge J., Georgakakis A., Hall P.B., Jiang L., Kinemuchi K., Malanushenko E.,
    Malanushenko V., Mcmahon R.G., Menzel M.-L., Merloni A., Nandra K.,
    Noterdaeme P., Oravetz D., Pan K., Pieri M.M., Prada F., Salvato M.,
    Schlegel D.J., Schneider D.P., Simmons A., Viel M., Weinberg D.H., Zhu L.
   <Astron. Astrophys., 597, A79 (2017)>
   =2017A&A...597A..79P    (SIMBAD/NED BibCode)
   =2017yCat.7278....0P
================================================================================
ADC_Keywords: Surveys ; QSOs ; Active gal. nuclei ; Spectroscopy
Keywords: catalogs - surveys - quasars: general
Abstract:
    We present the Data Release 12 Quasar catalog (DR12Q) from the Baryon
    Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky
    SurveyIII. This catalog includes all SDSS-III/BOSS objects that were
    spectroscopically targeted as quasar candidates during the full survey
    and that are confirmed as quasars via visual inspection of the
    spectra, have luminosities Mi[z=2]< -20.5 (in a {Lambda}CDM
    cosmology with H0=70km/s/Mpc, {Omega}M=0.3, and
    {Omega}{Lambda}=0.7), and either display at least one emission line
    with a full width at half maximum (FWHM) larger than 500km/s or, if
    not, have interesting/complex absorption features. The catalog also
    includes previously known quasars (mostly from SDSS-I andII) that were
    reobserved by BOSS. The catalog contains 297 301 quasars (272 026 are
    new discoveries since the beginning of SDSS-III) detected over
    9376deg2 with robust identification and redshift measured by a
    combination of principal component eigenspectra. The number of quasars
    with z>2.15 (184 101, of which 167 742 are new discoveries) is about
    an order of magnitude greater than the number of z>2.15 quasars known
    prior to BOSS. Redshifts and FWHMs are provided for the strongest
    emission lines (CIV, CIII], MgII). The catalog identifies 29 580 broad
    absorption line quasars and lists their characteristics. For each
    object, the catalog presents five-band (u, g, r, i, z) CCD-based
    photometry with typical accuracy of 0.03mag together with some
    information on the optical morphology and the selection criteria. When
    available, the catalog also provides information on the optical
    variability of quasars using SDSS and Palomar Transient Factory
    multi-epoch photometry. The catalog also contains X-ray, ultraviolet,
    near-infrared, and radio emission properties of the quasars, when
    available, from other large-area surveys. The calibrated digital
    spectra, covering the wavelength region 3600-10 500Å at a spectral
    resolution in the range 1300<R<2500, can be retrieved from the SDSS
    Catalog Archive Server. We also provide a supplemental list of an
    additional 4841 quasars that have been identified serendipitously
    outside of the superset defined to derive the main quasar catalog.
Description:
    We present the final quasar catalog of the SDSS-III/BOSS survey
    resulting from five years of observations. The catalog, which we call
    "DR12Q", contains 297301 quasars, 184101 of which have
    z>2.15. We provide robust identification from visual inspection and
    refined redshift measurements based on the result of a principal
    component analysis of the spectra. The present catalog contains about
    80% more quasars than our previous release (Paris et al., 2014, Cat.
    VII/270). As part of DR12Q, we also provide a catalog of 29580 BAL
    quasars and their properties. Spectroscopic line measurements are
    provided together with multi-wavelength matching with GALEX, 2MASS,
    UKIDSS, WISE, FIRST, RASS and XMM-Newton observations.
File Summary:
       FileName      Lrecl  Records   Explanations
×                   80        .   This file
× ReadMe            80        .   This file
× dr12q.dat       2742   297301   SDSS-DR12 Quasar Catalog
× DR12Q.fits      2880   186665   SDSS-DR12 Quasar Catalog (FITS)
× dr12qbal.dat    1525    29580   Detailed properties of BAL quasars
× DR12Q_BAL.fits  2880    10156   Detailed properties of BAL quasars (FITS)
× dr12qsp.dat      476     4841   Supplementary list that contains serendipitous
                                  quasars
× DR12Q_sup.fits  2880      388   Supplementary list that contains serendipitous
                                  quasars (FITS)
× dr12qspb.dat     476      226   Supplementary list that contains quasars
                                  identified on bad plates
× DR12Q_supbad.fits  2880       32   Supplementary list that contains quasars
                                  identified on bad plates (FITS)
See also:
   VII/270 : SDSS quasar catalog: tenth data release  (Paris+, 2014)
     V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)
Byte-by-byte Description of file:  dr12q.dat
   Bytes Format Units    Label     Explanations
   1- 18  A18   ---      SDSS      SDSS-DR12 designation HHMMSS.ss+DDMMSS.s
                                      (J2000) corrected by CDS
                                      (SDSS_NAMEc) (G1)
  20- 37  A18   ---      SDSSo     SDSS-DR12 designation HHMMSS.ss+DDMMSS.s
                                       (J2000) (SDSS_NAME) (G1)
  39- 48  F10.6 deg      RAdeg     Right Ascension (J2000) (RA)
  50- 59  F10.6 deg      DEdeg     Declination (J2000) (DEC)
  61- 70  I10   ---      THINGID   Thing_ID (unique identifier of SDSS
                                       sources) (THING_ID)
  72- 75  I4    ---      Plate     Spectroscopic Plate number (PLATE)
  77- 81  I5    ---      MJD       Spectroscopic MJD (MJD)
  83- 86  I4    ---      Fiber     Spectroscopic Fiber number (FIBERID)
  88- 95  F8.6  ---      z.v       Redshift from visual inspection (Z_VI)
  97-105  F9.6  ---      z.b       ?=-1 Redshift from BOSS pipeline (Z_PIPE)
 107-118  F12.6 ---      e_z.b     []?=-1 Error on BOSS pipeline redshift
                                       (error codes -4, -5, -6) (ERR_ZPIPE)
 120-122  I3    ---      f_z.b     ZWARNING flag (ZWARNING) (G3)
 124-132  F9.6  ---      z.PCA     Refined PCA redshift (Z_PCA) (G4)
 134-142  F9.6  ---      e_z.PCA   ?=-1 Error on refined PCA redshift
                                       (ERR_ZPCA)
 144-153  E10.4 ---      qCont     Estimator of the PCA continuum quality
                                       (PCA_QUAL)
 155-161  F7.4  ---      zCIV      Redshift of CIV emission line (Z_CIV)
 163-169  F7.4  ---      zCIII     Redshift of C iii] emission complex
                                       (Z_CIII)
 171-177  F7.4  ---      zMgII     Redshift of Mg ii emission line (Z_MGII)
 179-180  I2    ---      Morph     SDSS morphology flag
                                       0=point source 1=extended (SDSS_MORPHO)
 182-195  I14   ---      Btarg1    BOSS target flag for main survey
                                       (BOSS_TARGET1) (G5)
 197-215  I19   ---      Atarg1    BOSS target flag for ancillary programs
                                       (ANCILLARY_TARGET1) (G5)
 217-233  I17   ---      Atarg2    BOSS target flag for ancillary programs
                                       (ANCILLARY_TARGET2) (G5)
 235-247  I13   ---      eBtarg0   Target selection flag for the
                                      SDSS-IV/eBOSS pilot survey (EBOSS_TARGET0)
 249-250  I2    ---      NspBOSS   Number of additional spectra available in
                                       SDSS-III/BOSS (NSPEC_BOSS)
 251-442 32I6   ---      PlateDup  Spectroscopic plate number for each
                                       duplicate spectrum (PLATE_DUPLICATE)
 443-666 32I7   ---      MJDDup    Spectroscopic MJD for each duplicate
                                       spectrum (MJD_DUPLICATE)
 667-858 32I6   ---      FiberDup  Spectroscopic fiber number for each
                                       duplicate spectrum (FIBERID_DUPLICATE)
     860  I1    ---      f7        [0/1] 1 if the quasar is known from DR7
                                       (SDSS_DR7)
 862-866  I5    ---      Plate7    ?=-1 SDSS-DR7 spectroscopic Plate number
                                       if the quasar is known from DR7
                                       (PLATE_DR7)
 868-873  I6    ---      MJD7      ?=-1 SDSS-DR7 spectroscopic MJD if the
                                       quasar is known from DR7 (MJD_DR7)
 875-878  I4    ---      Fiber7    ?=-1 SDSS-DR7 spectroscopic Fiber number
                                       if the quasar is known from DR7
                                       (FIBERID_DR7)
     880  I1    ---      US        [0/2] Uniform sample flag (UNIFORM) (G6)
 882-890  F9.4  ---      alphanu   Spectral index measurement (ALPHA_NU)
 892-900  F9.4  ---      SNRSpec   Median signal-to-noise ratio over the
                                       whole spectrum (SNR_SPEC)
 901-1220 32F10.4 ---     SNRDup    Median signal-to-noise ratio over the
                                       whole spectrum of duplicate SDSS-III/BOSS
                                       spectra when available (SNR_DUPLICATE)
 1222-1230  F9.4  ---      SNR1700   Median signal-to-noise ratio in the
                                       window 1650-1750Å (rest frame)
                                       (SNR_1700)
 1232-1240  F9.4  ---      SNR3000   Median signal-to-noise ratio in the
                                       window 2950-3050Å (rest frame)
                                       (SNR_3000)
 1242-1250  F9.4  ---      SNR5150   Median signal-to-noise ratio in the
                                       window 5100-5250Å (rest frame)
                                       (SNR_5150)
 1252-1261  F10.4 km/s     FW(CIV)   ?=-1 FWHM of CIV emission line (FWHM_CIV)
 1263-1272  F10.4 km/s     HW(CIV)b  ?=-1 Blue HWHM of CIV emission line
                                       (BHWHM_CIV)
 1274-1283  F10.4 km/s     HW(CIV)r  ?=-1 Red HWHM of CIV emission line
                                       (RHWHM_CIV)
 1285-1293  F9.4  ---      A(CIV)    Amplitude of CIV emission line in units
                                       of median rms pixel noise (AMP_CIV)
 1295-1308  E14.7 0.1nm    W(CIV)    ?=-1 Rest frame equivalent width of CIV
                                       emission line in Å (REWE_CIV)
 1309-1321  E13.7 0.1nm    e_W(CIV)  ?=-1 Uncertainty on the rest frame
                                       equivalent width of CIV emission line
                                       (ERRREWECIV)
 1323-1332  F10.4 km/s     FW(CIII)  ?=-1 FWHM of CIII] emission complex
                                       (FWHM_CIII)
 1334-1343  F10.4 km/s    HW(CIII)b  ?=-1 Blue HWHM of CIII] emission line
                                       (BHWHM_CIII)
 1345-1354  F10.4 km/s    HW(CIII)r  ?=-1 Red HWHM of CIII] emission line
                                       (RHWHM_CIII)
 1356-1364  F9.4  ---      A(CIII)   Amplitude of CIII] emission complex in
                                      units of median rms pixel noise (AMP_CIII)
 1366-1378  E13.7 0.1nm    W(CIII)   ?=-1 Rest frame equivalent width of CIII]
                                       emission line in Å (REWE_CIII)
 1380-1392  E13.7 0.1nm   e_W(CIII)  ?=-1 Uncertainty on the rest frame
                                       equivalent width of CIII] emission
                                       complex (ERRREWECIII)
 1394-1403  F10.4 km/s     FW(MgII)  ?=-1 FWHM of MgII emission line
                                       (FWHM_MGII)
 1405-1414  F10.4 km/s    HW(MgII)b  ?=-1 Blue HWHM of MgII emission line
                                       (BHWHM_MGII)
 1416-1425  F10.4 km/s    HW(MgII)r  ?=-1 Red HWHM of MgII emission line
                                       (RHWHM_MGII)
 1427-1436  F10.4 ---      A(MgII)   Amplitude of MgII emission line in units
                                       of median rms pixel noise (AMP_MGII)
 1438-1450  E13.7 0.1nm    W(MgII)   ?=-1 Rest frame equivalent width of MgII
                                       emission line (REWE_MGII)
 1452-1464  E13.7 0.1nm   e_W(MgII)  ?=-1 Uncertainty on the rest frame
                                       equivalent width of MgII emission
                                       (ERRREWEMGII)
    1466  I1    ---      BAL-VI    [0/1] BAL flag from visual inspection
                                       (BALFLAGVI)
 1468-1477  F10.4 km/s     BI(CIVt)  ?=-1 Balnicity index of CIV trough
                                       (BI_CIV)
 1479-1488  F10.4 km/s   e_BI(CIVt)  ?=-1 Error on the Balnicity index of CIV
                                       trough (ERRBICIV)
 1490-1499  F10.4 km/s     AI(CIVt)  ?=-1 Absorption index of CIV trough
                                       (AI_CIV)
 1501-1510  F10.4 km/s   e_AI(CIVt)  ?=-1 Error on the absorption index of
                                       CIV trough (ERRAICIV)
 1512-1521  F10.4 ---      Chi2CIVt  ?=0 {chi}2 of the trough from Eq. (3) in
                                       Paris et al. (2012, Cat. VII/269)
                                       (CHI2TROUGH)
 1523-1524  I2    ---      N2t       Number of distinct CIV troughs of width
                                       larger than 2000km/s (NCIV_2000)
 1526-1535  F10.4 km/s     Vmin2t    ?=0  Minimum velocity of the CIV troughs
                                       (VMINCIV2000)
 1537-1546  F10.4 km/s     Vmax2t    ?=0  Maximum velocity of the CIV troughs
                                       (VMAXCIV2000)
 1548-1550  I3    ---      N.45t     Number of distinct CIV troughs of width
                                       larger than 450km/s (NCIV_450)
 1552-1561  F10.4 km/s     Vmin.45t  ?=0 Minimum velocity of the CIV troughs
                                       (VMINCIV450)
 1563-1572  F10.4 km/s     Vmax.45t  ?=0 Maximum velocity of the CIV troughs
                                       (VMAXCIV450)
 1574-1583  F10.4 0.1nm    W(SiIVt)  ?=0 Rest frame equivalent width of the
                                       Si iv trough (REW_SIIV)
 1585-1594  F10.4 0.1nm    W(CIVt)   ?=0 Rest frame equivalent width of the
                                       CIV trough (REW_CIV)
 1596-1605  F10.4 0.1nm   W(AlIIIt)  ?=0 Rest frame equivalent width of the
                                       AlIII] trough (REW_ALIII)
 1607-1610  I4    ---      RUN       SDSS Imaging Run Number of photometric
                                       measurements (RUN_NUMBER)
 1612-1616  I5    ---      Ph-MJD    Modified Julian Date of imaging
                                       observation (PHOTO_MJD)
 1618-1620  A3    ---      Rerun     SDSS Photometric Processing Rerun Number
                                       (RERUN_NUMBER)
    1622  I1    ---      Colcam    [1/6]?=0 SDSS Camera Column Number
                                       (COL_NUMBER)
 1624-1626  I3    ---      Field     SDSS Field Number (FIELD_NUMBER)
 1628-1646  A19   ---      objID     SDSS Object Identification Number (OBJ_ID)
 1648-1659  E12.6 3.63uJy  Fu        ?=-9999 PSF flux in u band (not corrected
                                       for Galactic extinction)
                                       in nnomggies (PSFFLUXu) (G2)
 1661-1672  E12.6 3.63uJy  Fg        ?=-9999 PSF flux in g band (not corrected
                                       for Galactic extinction)
                                       in nnomggies (PSFFLUXg) (G2)
 1674-1685  E12.6 3.63uJy  Fr        ?=-9999 PSF flux in r band (not corrected
                                       for Galactic extinction) in nnomggies
                                       (PSFFLUXr) (G2)
 1687-1698  E12.6 3.63uJy  Fi        ?=-9999 PSF flux in i band (not corrected
                                       for Galactic extinction) in nnomggies
                                       (PSFFLUXi) (G2)
 1700-1711  E12.6 3.63uJy  Fz        ?=-9999 PSF flux in z band (not corrected
                                       for Galactic extinction) in nnomggies
                                       (PSFFLUXz) (G2)
 1713-1722  F10.6 3.63uJy  IVFu      Inverse variance of of PSF flux in u band
                                       in nnomggies (IVAR_PSFFLUXu) (G2)
 1724-1733  F10.6 3.63uJy  IVFg      Inverse variance of of PSF flux in g band
                                       in nnomggies (IVAR_PSFFLUXg) (G2)
 1735-1744  F10.6 3.63uJy  IVFr      Inverse variance of of PSF flux in r band
                                       in nnomggies (IVAR_PSFFLUXr) (G2)
 1746-1755  F10.6 3.63uJy  IVFi      Inverse variance of of PSF flux in i band
                                       in nnomggies (IVAR_PSFFLUXi) (G2)
 1757-1766  F10.6 3.63uJy  IVFz      Inverse variance of of PSF flux in z band
                                       in nnomggies (G2) (IVAR_PSFFLUXz)
 1768-1779  E12.6 mag      umag      ?=-9999 PSF magnitude in u band (not
                                       corrected for Galactic extinction)
                                        (PSFMAGu)
 1781-1792  E12.6 mag      gmag      ?=-9999 PSF magnitude in g band (not
                                       corrected for Galactic extinction)
                                        (PSFMAGg)
 1794-1805  E12.6 mag      rmag      ?=-9999 PSF magnitude in r band (not
                                       corrected for Galactic extinction)
                                        (PSFMAGr)
 1807-1818  E12.6 mag      imag      ?=-9999 PSF magnitude in i band (not
                                       corrected for Galactic extinction)
                                        (PSFMAGi)
 1820-1831  E12.6 mag      zmag      ?=-9999 PSF magnitude in z band (not
                                       corrected for Galactic extinction)
 1833-1844  E12.6 mag      e_umag    ?=-9999 error in PSF magnitude in u band
                                        (ERR_PSFMAGu)
 1846-1857  E12.6 mag      e_gmag    ?=-9999 error in PSF magnitude in g band
                                        (ERR_PSFMAGg)
 1859-1870  E12.6 mag      e_rmag    ?=-9999 error in PSF magnitude in r band
                                        (ERR_PSFMAGr)
 1872-1883  E12.6 mag      e_imag    ?=-9999 error in PSF magnitude in i band
                                        (ERR_PSFMAGi)
 1885-1896  E12.6 mag      e_zmag    ?=-9999 error in PSF magnitude in z band
                                        (ERR_PSFMAGz)
 1898-1909  E12.6 3.63uJy  Fut       ?=-9999 Target flux in the u band
                                       (not corrected for Galactic extinction)
                                       in nnomggies (G2) (TARGET_FLUXu)
 1911-1922  E12.6 3.63uJy  Fgt       ?=-9999 Target flux in the g band
                                       (not corrected for Galactic extinction)
                                       in nnomggies (G2) (TARGET_FLUXg)
 1924-1935  E12.6 3.63uJy  Frt       ?=-9999 Target flux in the r band
                                        (not corrected for Galactic extinction)
                                        in nnomggies (G2) (TARGET_FLUXr)
 1937-1948  E12.6 3.63uJy  Fit       ?=-9999 Target flux in the i band
                                        (not corrected for Galactic extinction)
                                        in nnomggies (G2) (TARGET_FLUXi)
 1950-1961  E12.6 3.63uJy  Fzt       ?=-9999 Target flux in the z band
                                        (not corrected for Galactic extinction)
                                        in nnomggies (G2) (TARGET_FLUXz)
 1963-1975  F13.6 mag      iMAG      ? Absolute i magnitude (1)
 1977-1989  F13.6 mag      D(g-i)    ? {Delta}(g-i)=(g-i)-<(g-i)>redshift
                                       (Galactic extinction corrected)
                                       (DGMI) (G7)
 1991-1998  F8.6  mag      Extu      ? Galactic extinction in u band
                                       (EXTINCTIONu) (G8)
 2000-2007  F8.6  mag      Extg      ? Galactic extinction in g band
                                       (EXTINCTIONg) (G8)
 2009-2016  F8.6  mag      Extr      ? Galactic extinction in r band
                                       (EXTINCTIONr) (G8)
 2018-2025  F8.6  mag      Exti      ? Galactic extinction in i band
                                       (EXTINCTIONi) (G8)
 2027-2034  F8.6  mag      Extz      ? Galactic extinction in z band
                                       (EXTINCTIONz) (G8)
 2036-2043  F8.6  mag      ExtuR     Recalculated Galactic extinction in u
                                       (EXTINCTION_RECALu) (G9)
 2045-2052  F8.6  mag      ExtgR     Recalculated Galactic extinction in g
                                       (EXTINCTION_RECALg) (G9)
 2054-2061  F8.6  mag      ExtrR     Recalculated Galactic extinction in r
                                       (EXTINCTION_RECALr) (G9)
 2063-2070  F8.6  mag      ExtiR     Recalculated Galactic extinction in i
                                       (EXTINCTION_RECALi) (G9)
 2072-2079  F8.6  mag      ExtzR     Recalculated Galactic extinction in z
                                       (EXTINCTION_RECALz) (G9)
 2081-2087  F7.4  [cm-2]   logNHI    logarithm of Galactic HI column density
                                        (HI_GAL)
 2089-2091  I3    ---      Varmatch  Flag for variability information
                                       (0 if not available) (VAR_MATCHED)
 2093-2099  F7.2  ---      Varchi2   Reduced {chi}2 when the light curve is
                                       fit with a constant (VAR_CHI2)
 2101-2107  F7.5  ---      VarA      Structure function parameter A as defined
                                       in Palanque-Delabrouille et al.
                                       (2011A&A...530A.122P) (VAR_A)
 2109-2116  F8.5  -        Vargamma  Structure function parameter {gamma} as
                                       defined in Palanque-Delabrouille et al.
                                       (2011A&A...530A.122P) (VAR_GAMMA)
 2118-2123  F6.4  [ct/s]   logXct    log RASS full band count rate
                                       (RASS_COUNTS)
 2125-2131  F7.4  ---      SNR(X)    S/N of the RASS count rate
                                        (RASSCOUNTSSNR)
 2133-2139  F7.4  arcsec   sepX      SDSS-RASS separation in arcsec
                                        (SDSS2ROSAT_SEP)
 2141-2146  I6    ---      NDetX     Number of detections in XMM-Newton
                                        (NDETECTIONXMM)
 2148-2158  E11.6 mW/m2    F0.2-12   Total flux (0.2-12keV) from XMM-Newton
                                       computed from the longest observation
                                       FLUX0212KEVSGL)
 2160-2170  E11.6 mW/m2   e_F0.2-12  Error in total flux (0.2-12keV) from
                                       XMM-NewtonRFLUX0212KEV_SGL)
 2172-2182  E11.6 mW/m2    F0.2-2    Soft (0.2-2keV) X-ray flux from
                                       XMM-Newton (FLUX02_2KEV)
 2184-2194  E11.6 mW/m2    e_F0.2-2  Error in soft (0.2-2keV) X-ray flux from
                                       XMM-Newton (ERRFLUX022KEV)
 2196-2206  E11.6 mW/m2    F4.5-12   Hard (4.5-12keV) X-ray flux from
                                       XMM-Newton (FLUX2_12KEV)
 2208-2218  E11.6 mW/m2   e_F4.5-12  Error in hard (4.5-12keV) X-ray flux
                                       from XMM-Newton (ERRFLUX212KEV)
 2220-2230  E11.6 mW/m2    F0.2-12W  Total weighted average flux (0.2-12keV)
                                       from XMM-Newton (FLUX02_12KEV)
 2232-2242  E11.6 mW/m2  e_F0.2-12W  Error in total flux (0.2-12keV)
                                       from XMM-Newton (ERRFLUX0212KEV)
 2244-2254  E11.6 10-7W    L0.2-12   Total X-ray luminosity (0.2-12keV) from
                                       XMM-Newton using the longest observation
                                        (LUM022KEVSGL) (2)
 2256-2266  E11.6 10-7W    L0.5-2    Soft (0.2-2keV) X-ray luminosity from
                                       XMM-Newton (LUM05_2KEV) (2)
 2268-2278  E11.6 10-7W    L4.5-12   Hard (4.5-12keV) X-ray luminosity from
                                       XMM-Newton (LUM2_12KEV) (2)
 2280-2290  E11.6 10-7W    L0.2-2W   Total X-ray luminosity (0.2-12keV) from
                                       XMM-Newton using weighted average flux
                                       (LUM02_2KEV) (2)
 2296-2297  I2    ---     f_F4.5-12  [0/1]?=-1 Flag for upper limit of hard
                                       X-ray flux (LUMX210UPPER)
 2299-2304  F6.4  arcsec   sepXM     ?=0 SDSS-XMM-Newton separation in arcsec
                                       (SDSS2XMM_SEP)
    2306  I1    ---      GALEX     GALEX match (GALEX_MATCHED)
 2308-2316  F9.4  3.63uJy  FFUV      ?=0 FUV flux (GALEX) (FUV)
 2318-2327  F10.4 3.63uJy-2 IVFUV    ?=0 Inverse variance of FUV flux
                                       (in nnomggies-2) (FUV_IVAR)
 2329-2337  F9.4  3.63uJy  FNUV      ?=0 NUV flux (GALEX) (NUV)
 2339-2348  F10.4 3.63uJy-2 IVNUV    ?=0 Inverse variance of NUV flux
                                       (in nnomggies-2) (NUV_IVAR)
 2350-2356  F7.4  mag      Jmag      ?=0 2MASS J magnitude (Vega) (JMAG)
 2358-2367  F10.4 mag      e_Jmag    ?=0 Error in J magnitude (Vega)
                                       (ERR_JMAG)
 2369-2378  F10.4 ---      SNR(J)    ?=0 J-band S/N (JSNR)
    2380  I1    ---      f_Jmag    ?=0 J-band photometry flag (JRDFLAG)
 2382-2388  F7.4  mag      Hmag      ?=0 2MASS H magnitude (Vega) (HMAG)
 2390-2399  F10.4 mag      e_Hmag    ?=0 Error in H magnitude (ERR_HMAG)
 2401-2410  F10.4 ---      SNR(H)    ?=0 H-band S/N (HSNR)
    2412  I1    ---      f_Hmag    ?=0 H-band photometry flag (HRDFLAG)
 2414-2420  F7.4  mag      Kmag      ?=0 2MASS K magnitude (Vega) (KMAG)
 2422-2431  F10.4 mag      e_Kmag    ?=0 Error in K magnitude (ERR_KMAG)
 2433-2442  F10.4 ---      SNR(K)    ?=0 K-band S/N (KSNR)
    2444  I1    ---      f_Kmag    ?=0 K-band photometry flag (KRDFLAG)
 2446-2452  F7.4  arcsec   Sep2      ?=0 SDSS-2MASS separation in arcsec
                                       (SDSS2MASS_SEP)
 2454-2460  F7.4  mag      W1mag     ?=0 WISE W1 magnitude (Vega) (W1MAG)
 2462-2470  F9.4  mag      e_W1mag   ?=0 Error in W1 magnitude (ERR_W1MAG)
 2472-2478  F7.4  ---      W1SNR     ?=0 S/N in W1 band (W1SNR)
 2480-2486  F7.4  ---      W1chi2    ?=0 {chi}2 in W1 band (W1CHI2)
 2488-2494  F7.4  mag      W2mag     ?=0 WISE W2 magnitude (Vega) (W2MAG)
 2496-2504  F9.4  mag      e_W2mag   ?=0 Error in W2 magnitude (ERR_W2MAG)
 2506-2513  F8.4  ---      W2SNR     ?=0 S/N in W2 band (W2SNR)
 2515-2521  F7.4  ---      W2chi2    ?=0 {chi}2 in W2 band (W2CHI2)
 2523-2529  F7.4  mag      W3mag     ?=0 WISE W3 magnitude (Vega) (W3MAG)
 2531-2539  F9.4  mag      e_W3mag   ?=0 Error in W3 magnitude
                                       (ERR_W3MAG)
 2541-2548  F8.4  ---      W3SNR     ?=0 S/N in W3 band (W3SNR)
 2550-2557  F8.4  ---      W3chi2    ?=0 {chi}2 in W3 band (W3CHI2)
 2559-2565  F7.4  mag      W4mag     ?=0 WISE W4 magnitude (Vega) (W4MAG)
 2567-2575  F9.4  mag      e_W4mag   ?=0 Error in W4 magnitude
                                       (ERR_W4MAG)
 2577-2583  F7.4  ---      W4SNR     S/N in W4 band (W4SNR)
 2585-2587  F3.1  ---      W4chi2    {chi}2 in W4 band (W4CHI2)
 2589-2592  A4    ---      CCflags   WISE contamination and confusion flag
                                       (CC_FLAGS)
 2594-2597  A4    ---      PHflag    WISE photometric quality flag (PH_FLAG)
 2599-2604  F6.4  arcsec   sepW      SDSS-WISE separation in arcsec
                                       (SDSS2WISE_SEP)
    2606  I1    ---      UKIDSS    UKIDSS Matched (UKIDSS_MATCHED)
 2608-2619  E12.6 W/m2/Hz  FY        Y-band flux density from UKIDSS (YFLUX)
 2621-2632  E12.6 W/m2/Hz  e_FY      ?=0 Error in Y-band density flux from
                                       UKIDSS (YFLUX_ERR)
 2634-2645  E12.6 W/m2/Hz  FJ        ?=0 J-band flux density from UKIDSS
                                       (JFLUX)
 2647-2658  E12.6 W/m2/Hz  e_FJ      ?=0 Error in J-band flux density from
                                       UKIDSS (JFLUX_ERR)
 2660-2671  E12.6 W/m2/Hz  FH        ?=0 H-band flux density from UKIDSS
                                       (HFLUX)
 2673-2684  E12.6 W/m2/Hz  e_FH      ?=0 Error in H-band flux density from
                                       UKIDSS (HFLUX_ERR)
 2686-2697  E12.6 W/m2/Hz  FK        ?=0 K-band flux density from UKIDSS
                                       (KFLUX)
 2699-2710  E12.6 W/m2/Hz  e_FK      ?=0 Error in K-band flux density from
                                       UKIDSS (KFLUX_ERR)
 2712-2713  I2    ---      FIRST     FIRST matched (FIRST_MATCHED)
 2715-2724  F10.4 mJy      F1p       ?=0 FIRST peak flux density at 20 cm
                                       expressed in mJy (FIRST_FLUX)
 2726-2735  F10.4 ---      SNR(1)    ?=0 S/N of the FIRST flux density
                                       (FIRST_SNR)
 2737-2742  F6.4  arcsec   sep1      ?=0 SDSS-FIRST separation in arcsec
                                       (SDSS2FIRST_SEP)
Note (1): [z=2](H0=67.8km/s/Mpc, {OMEGA}M=0.308, {OMEGA}_{lambda}=0.692,
    {alpha}v=-0.5 (MI)
Note (2): using Z_VI and H0=70km/s/Mpc, {OMEGA}M=0.3, {OMEGA}_{lambda}=0.7
Byte-by-byte Description of file:  dr12qbal.dat
   Bytes Format Units   Label       Explanations
   1- 18  A18   ---     SDSS        SDSS-DR12 designation HHMMSS.ss+DDMMSS.s
                                       (J2000) corrected by CDS
                                       (SDSS_NAMEc) (G1)
  20- 37  A18   ---     SDSSo       SDSS-DR12 designation HHMMSS.ss+DDMMSS.s
                                       (J2000) (SDSS_NAME) (G1)
  39- 48  F10.6 deg     RAdeg       Right Ascension (J2000) (RA)
  50- 59  F10.6 deg     DEdeg       Declination (J2000) (DEC)
  61- 70  I10   ---     THINGID     Thing_ID (unique SDSS source identifier)
                                       (THING_ID)
  72- 75  I4    ---     Plate       Spectroscopic Plate number (PLATE)
  77- 81  I5    ---     MJD         Spectroscopic MJD (MJD)
  83- 86  I4    ---     Fiber       Spectroscopic Fiber number (FIBERID)
  88- 95  F8.6  ---     z.v         Redshift from visual inspection (Z_VI)
  97-105  F9.6  ---     z.b         ?=-1 Redshift from BOSS pipeline (Z_PIPE)
 107-116  F10.6 ---     e_z.b       []?=-1 Error on BOSS pipeline redshift
                                       (error codes -4, -5, -6) (ERR_ZPIPE)
 118-120  I3    ---     f_z.b       ZWARNING flag (ZWARNING) (G3)
 122-130  F9.6  ---     z.PCA       ?=-1 PCA redshift (Z_PCA) (G4)
 132-140  F9.6  ---     e_z.PCA     ?=-1 Error on PCA redshift (ERR_ZPCA)
 142-143  I2    ---     Morph       [0/1]?=-1 SDSS morphology flag
                                       0=point source 1=extended (SDSS_MORPHO)
 145-158  I14   ---     Btarg1      BOSS target flag for main survey
                                       (BOSS_TARGET1) (G5)
 160-178  I19   ---     Atarg1      BOSS target flag for ancillary programs
                                       (ANCILLARY_TARGET1) (G5)
 180-196  I17   ---     Atarg2      BOSS target flag for ancillary programs
                                       (ANCILLARY_TARGET2) (G5)
 198-210  I13   ---     eBtarg0     Target selection flag for eBOSS pilot
                                       survey  (EBOSS_TARGET0)
 212-222  F11.6 3.63uJy Fu          PSF flux in the u band (not corrected for
                                       Galactic extinction) in nnomggies unit
                                       (PSFFLUXu) (G2)
 224-234  F11.6 3.63uJy Fg          PSF flux in the g band (not corrected for
                                       Galactic extinction) in nnomggies unit
                                       (PSFFLUXg) (G2)
 236-246  F11.6 3.63uJy Fr          PSF flux in the r band (not corrected for
                                       Galactic extinction) in nnomggies unit
                                       (PSFFLUXr) (G2)
 248-258  F11.6 3.63uJy Fi          PSF flux in the i band (not corrected for
                                       Galactic extinction) in nnomggies unit
                                       (PSFFLUXi) (G2)
 260-270  F11.6 3.63uJy Fz          PSF flux in the z band (not corrected for
                                       Galactic extinction) in nnomggies unit
                                       (PSFFLUXz) (G2)
 272-281  F10.6 ---     IVFu        Inverse variance of u flux (IVAR_PSFFLUXu)
 283-292  F10.6 ---     IVFg        Inverse variance of g flux (IVAR_PSFFLUXg)
 294-303  F10.6 ---     IVFr        Inverse variance of r flux (IVAR_PSFFLUXr)
 305-314  F10.6 ---     IVFi        Inverse variance of i flux (IVAR_PSFFLUXi)
 316-325  F10.6 ---     IVFz        Inverse variance of z flux (IVAR_PSFFLUXz)
 327-335  F9.6  mag     umag        PSF magnitude in u band (not corrected for
                                       Galactic extinction) (PSFMAGu)
 337-345  F9.6  mag     gmag        PSF magnitude in g band (not corrected for
                                       Galactic extinction) (PSFMAGg)
 347-355  F9.6  mag     rmag        PSF magnitude in r band (not corrected for
                                       Galactic extinction) (PSFMAGr)
 357-365  F9.6  mag     imag        PSF magnitude in i band (not corrected for
                                       Galactic extinction) (PSFMAGi)
 367-375  F9.6  mag     zmag        PSF magnitude in z band (not corrected for
                                       Galactic extinction) (PSFMAGz)
 377-386  F10.6 mag     e_umag      Error in u PSF magnitude (ERR_PSFMAGu)
 388-397  F10.6 mag     e_gmag      Error in g PSF magnitude (ERR_PSFMAGg)
 399-408  F10.6 mag     e_rmag      Error in r PSF magnitude (ERR_PSFMAGr)
 410-419  F10.6 mag     e_imag      Error in i PSF magnitude (ERR_PSFMAGi)
 421-430  F10.6 mag     e_zmag      Error in z PSF magnitude (ERR_PSFMAGz)
 432-439  F8.6  mag     Extu        Galactic extinction in u band
                                        (EXTINCTIONu) (G8)
 441-448  F8.6  mag     Extg        Galactic extinction in g band
                                        (EXTINCTIONg) (G8)
 450-457  F8.6  mag     Extr        Galactic extinction in r band
                                        (EXTINCTIONr) (G8)
 459-466  F8.6  mag     Exti        Galactic extinction in i band
                                        (EXTINCTIONi) (G8)
 468-475  F8.6  mag     Extz        Galactic extinction in z band
                                        (EXTINCTIONz) (G8)
 477-485  F9.6  ---     SNRspec     Median signal-to-noise ratio per pixel
                                       over the whole spectrum (SNR_SPEC)
 487-496  F10.6 ---     SNR1700     Median signal-to-noise ratio per pixel in
                                      the window 1650-1750Å (rest frame)
                                       (SNR_1700)
 498-506  F9.6  ---     SNR3000     Median signal-to-noise ratio per pixel in
                                      the window 2950-3050Å (rest frame)
                                       (SNR_3000)
 508-517  F10.4 km/s    BI(CIVt)    ?=-1 Balnicity Index (BI) (BI_CIV)
 519-528  F10.4 km/s    e_BI(CIVt)  ?=-1 Error on Balnicity index (ERRBICIV)
 530-531  I2    ---     N2t         Number of troughs wider than 2000km/s
                                       (NCIV_2000)
 533-542  F10.4 ---     Vmin2t1     Minimum velocity of each detected
                                       absorption trough (VMINCIV2000_1)
 544-553  F10.4 ---     Vmin2t2     Minimum velocity of each detected
                                       absorption trough (VMINCIV2000_2)
 555-564  F10.4 ---     Vmin2t3     Minimum velocity of each detected
                                       absorption trough (VMINCIV2000_3)
 566-575  F10.4 ---     Vmin2t4     Minimum velocity of each detected
                                       absorption trough (VMINCIV2000_4)
 577-586  F10.4 ---     Vmin2t5     Minimum velocity of each detected
                                       absorption trough (VMINCIV2000_5)
 588-597  F10.4 ---     Vmax2t1     Maximum velocity of each detected
                                       absorption trough (VMAXCIV2000_1)
 599-608  F10.4 ---     Vmax2t2     Maximum velocity of each detected
                                       absorption trough (VMAXCIV2000_2)
 610-619  F10.4 ---     Vmax2t3     Maximum velocity of each detected
                                       absorption trough (VMAXCIV2000_3)
 621-630  F10.4 ---     Vmax2t4     Maximum velocity of each detected
                                       absorption trough (VMAXCIV2000_4)
 632-641  F10.4 ---     Vmax2t5     Maximum velocity of each detected
                                       absorption trough (VMAXCIV2000_5)
 643-652  F10.4 km/s    posmin2t1   Position of the minimum of each absorption
                                       trough (POSMINCIV2000_1)
 654-663  F10.4 km/s    posmin2t2   Position of the minimum of each absorption
                                       trough (POSMINCIV2000_2)
 665-674  F10.4 km/s    posmin2t3   Position of the minimum of each absorption
                                       trough (POSMINCIV2000_3)
 676-685  F10.4 km/s    posmin2t4   Position of the minimum of each absorption
                                       trough (POSMINCIV2000_4)
 687-696  F10.4 km/s    posmin2t5   Position of the minimum of each absorption
                                       trough (POSMINCIV2000_5)
 698-707  F10.4 ---     Fmin2t1     Normalized flux density at the minimum of
                                       each absorption trough (FMINCIV2000_1)
 709-718  F10.4 ---     Fmin2t2     Normalized flux density at the minimum of
                                       each absorption trough (FMINCIV2000_2)
 720-729  F10.4 ---     Fmin2t3     Normalized flux density at the minimum of
                                       each absorption trough (FMINCIV2000_3)
 731-740  F10.4 ---     Fmin2t4     Normalized flux density at the minimum of
                                       each absorption trough (FMINCIV2000_4)
 742-751  F10.4 ---     Fmin2t5     Normalized flux density at the minimum of
                                       each absorption trough (FMINCIV2000_5)
 753-762  F10.4 km/s    AI(CIVt)    ?=-1 Absorption index (AI) (AI_CIV)
 764-773  F10.4 km/s    e_AI(CIVt)  ?=-1 Error on absorption index
                                        (ERRAICIV)
 775-777  I3    ---     N.45t       ?=-1 Number of absorption trough wider
                                       than 450km/s (NCIV_450)
 778-788  F11.4 ---     Vmin.45t1   ?=-1 Minimum velocity of first detected
                                         absorption trough (VMINCIV450)
 789-964 16F11.4 ---    Vmin.45to   ?=-1 Minimum velocity of others detected
                                       absorption troughs (VMINCIV450)
 965-975  F11.4 ---     Vmax.45t1   ?=-1 Maximum velocity of first detected
                                       absorption trough (VMAXCIV450)
 976-1151 16F11.4 ---    Vmax.45to   ?=-1 Maximum velocity of other detected
                                       absorption troughs (VMAXCIV450)
 1152-1162  F11.4 km/s   posmin.45t1  ?=-1 Position of the minimum of first
                                       absorption trough (POSMINCIV450)
 1163-1338 16F11.4 km/s  posmin.45to  ?=-1 Position of the minimum of other
                                       absorption troughs (POSMINCIV450)
 1339-1349  F11.4 ---     Fmin.45t1   ?=-1 Normalized flux density at the
                                       minimum of first absorption trough
                                       (FMINCIV450)
 1350-1525 16F11.4 ---    Fmin.45to   ?=-1 Normalized flux density at the
                                       minimum of other absorption troughs
                                       (FMINCIV450)
Byte-by-byte Description of file:  dr12qsp.dat  dr12qspb.dat
   Bytes Format Units     Label   Explanations
   1- 18  A18   ---       SDSS    SDSS-DR12 designation HHMMSS.ss+DDMMSS.s
                                   (J2000) corrected by CDS (SDSS_NAMEc) (G1)
  20- 37  A18   ---       SDSSo   SDSS-DR12 designation HHMMSS.ss+DDMMSS.s
                                   (J2000) (SDSS_NAME) (G1)
  39- 48  F10.6 deg       RAdeg   Right Ascension (J2000) (RA)
  50- 59  F10.6 deg       DEdeg   Declination (J2000) (DEC)
  61- 70  I10   ---      THINGID  Thing_ID (THING_ID)
  72- 75  I4    ---       Plate   Spectroscopic Plate number (PLATE)
  77- 81  I5    ---       MJD     Spectroscopic MJD (MJD)
  83- 86  I4    ---       Fiber   Spectroscopic Fiber number (FIBERID)
  88- 95  F8.6  ---       z.v     Redshift from visual inspection (Z_VI)
  97-105  F9.6  ---       z.b     ?=-1 Redshift from BOSS pipeline (Z_PIPE)
 107-116  F10.6 ---       e_z.b   []?=-1 Error on BOSS pipeline redshift
                                   (error codes -4, -5, -6) (ERR_ZPIPE)
 118-120  I3    ---       f_z.b   ZWARNING flag|(ZWARNING) (G4)
 122-123  I2    ---       Morph   SDSS morphology flag
                                   0=point source 1=extended|(SDSS_MORPHO)
 125-138  I14   ---       Btarg1  BOSS target flag for main survey
                                   (BOSS_TARGET1)
 140-158  I19   ---       Atarg1  BOSS target flag for ancillary programs
                                   (ANCILLARY_TARGET1)
 160-178  I19   ---       Atarg2  BOSS target flag for ancillary programs
                                   (ANCILLARY_TARGET2)
 180-189  I10   ---      eBtarg0  Target selection flag for eBOSS pilot survey
                                   (EBOSS_TARGET0)
     191  I1    ---       BAL-VI  BAL flag from visual inspection|(BALFLAGVI)
 193-211  A19   ---       objID   SDSS Object Identification Number|(OBJ_ID)
 213-223  F11.6 3.63uJy   Fu      ?=0 PSF flux in u band (not corrected
                                   for Galactic extinction)
                                   in nnomggies (PSFFLUXu)(G2)
 225-235  F11.6 3.63uJy   Fg      ?=0 PSF flux in g band (not corrected
                                   for Galactic extinction)
                                   in nnomggies (PSFFLUXg)(G2)
 237-247  F11.6 3.63uJy   Fr      ?=0 PSF flux in r band (not corrected
                                   for Galactic extinction)
                                   in nnomggies (PSFFLUXr)(G2)
 249-259  F11.6 3.63uJy   Fi      ?=0 PSF flux in i band (not corrected
                                   for Galactic extinction)
                                   in nnomggies (PSFFLUXi)(G2)
 261-271  F11.6 3.63uJy   Fz      ?=0 PSF flux in z band (not corrected
                                   for Galactic extinction)
                                   in nnomggies (PSFFLUXz)(G2)
 273-282  F10.6 3.63uJy   IVFu    Inverse variance of PSF flux in u band
                                   in nnomggies (IVAR_PSFFLUXu) (G2)
 284-293  F10.6 3.63uJy   IVFg    Inverse variance of PSF flux in g band
                                   in nnomggies (IVAR_PSFFLUXg) (G2)
 295-304  F10.6 3.63uJy   IVFr    Inverse variance of PSF flux in r band
                                   in nnomggies (IVAR_PSFFLUXr) (G2)
 306-315  F10.6 3.63uJy   IVFi    Inverse variance of PSF flux in i band
                                   in nnomggies (IVAR_PSFFLUXi) (G2)
 317-326  F10.6 3.63uJy   IVFz    Inverse variance of PSF flux in z band
                                   in nnomggies (G2) (IVAR_PSFFLUXz)
 328-336  F9.6  mag       umag    PSF magnitude in u band (not corrected for
                                   Galactic extinction) (PSFMAGu)
 338-346  F9.6  mag       gmag    PSF magnitude in g band (not corrected for
                                   Galactic extinction) (PSFMAGg)
 348-356  F9.6  mag       rmag    PSF magnitude in r band (not corrected for
                                   Galactic extinction) (PSFMAGr)
 358-366  F9.6  mag       imag    PSF magnitude in i band (not corrected for
                                   Galactic extinction) (PSFMAGi)
 368-376  F9.6  mag       zmag    PSF magnitude in z band (not corrected for
                                   Galactic extinction) (PSFMAGz)
 378-386  F9.6  mag       e_umag  Error in PSF magnitude in u band (ERR_PSFMAGu)
 388-396  F9.6  mag       e_gmag  Error in PSF magnitude in g band (ERR_PSFMAGg)
 398-406  F9.6  mag       e_rmag  Error in PSF magnitude in r band (ERR_PSFMAGr)
 408-416  F9.6  mag       e_imag  Error in PSF magnitude in i band (ERR_PSFMAGi)
 418-426  F9.6  mag       e_zmag  Error in PSF magnitude in z band (ERR_PSFMAGz)
 428-436  F9.6  mag       Extu    Galactic extinction in u band
                                   (EXTINCTIONu) (G8)
 438-446  F9.6  mag       Extg    Galactic extinction in g band
                                   (EXTINCTIONg) (G8)
 448-456  F9.6  mag       Extr    Galactic extinction in r band
                                   (EXTINCTIONr) (G8)
 458-466  F9.6  mag       Exti    Galactic extinction in i band
                                   (EXTINCTIONi) (G8)
 468-476  F9.6  mag       Extz    Galactic extinction in z band
                                   (EXTINCTIONz) (G8)
Global notes:
Note (G1): Some SDSS names were erroneous. The corrected names have been
  added by CDS.
Note (G2): In SDSS-III, we express all fluxes in terms of "nnomggies",
  which are a convenient linear unit. These quantities are related to
  standard AB magnitudes: an object with flux F given  in nMgy has a
  Pogson magnitude (on AB scale) m=[22.5mag]-2.5log10F. A flux of 1Mgy
  is therefore close to 3631Jy, and 1nMgy=~3.631µJy.
Note (G3): the "zwarning" flag is made of the following bits:
     1 [0] = sky fiber
     2 [1] = too little wavelength coverage
     4 [2] = chi-squared of best fit is too close to that of second best
     8 [3] = synthetic spectrum is negative
    16 [4] = fraction of points more than 5{sigma} away from best model
              is too large (>5%)
    32 [5] = chi-squared minimum at edge of the redshift fitting range
    64 [6] = a QSO line exhibits negative emission (triggered only in QSO
              spectra if CIV, CIII, MgII, H{beta}, or H{alpha} has
              lineArea+3{sigma}(lineArea)<0)
    128 [7] = the fiber was unplugged, so no spectrum obtained
Note (G4): Principal Component Analysis of quasar spectra, see
    Paris et al. 2011, Cat. J/A+A/530/A50; the quality is defined
    by Eq.(11) in Paris et al. (2011A&A...530A..50P)
Note (G5): See Dawson et al. 2013AJ....145...10D for the description
    of the target selection flags.
Note (G6): quasars selected by XDQSO (eXtreme Deconvolution method):
    a positive "uniform" flag indicates QSOs in a sufficiently
    statistical sample for, e.g., clustering measurements.
    1 indicates a core target, and 2 a quite complete core.
Note (G7): {Delta}(g-i) is the difference in (g-i), Galactic extinction
     corrected, between the quasar and the mean of the quasars at that
     redshift. {Delta}(g-i) is not defined for quasars at either z<0.12
     or z>5.12.
Note (G8): from Schlegel et al.  (1998ApJ...500..525S)
Note (G9): from Schlafly & Finkbeiner (2011ApJ...737..103S)
History:
    Copied at http://www.sdss.org/dr12/algorithms/boss-dr12-quasar-catalog/
================================================================================
(End)                                      Patricia Vannier [CDS]    28-Jun-2017