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SDSSQUASAR - Sloan Digital Sky Survey Quasar Catalog (10th Data Release: DR10Q)

HEASARC
Archive

Overview

This table contains the Data Release 10 Quasar (DR10Q) catalog from the Baryon Oscillation Spectroscopic Survey (BOSS) of the Sloan Digital Sky Survey III. The catalog includes all BOSS objects that were targeted as quasar candidates during the first 2.5 years of the survey and that are confirmed as quasars via visual inspection of the spectra, have luminosities Mi [z = 2] < -20.5 (in a LambdaCDM cosmology with H0 = 70 km s-1 Mpc-1 , OmegaM = 0.3, and OmegaLambda = 0.7), and either display at least one emission line with a full width at half maximum (FWHM) larger than 500 km s-1 or, if not, have interesting/complex absorption features. The catalog also includes known quasars (mostly from SDSS-I and II) that were re-observed by BOSS. The catalog contains 166,583 quasars (74,454 are new discoveries since SDSS-DR9) detected over 6,373 deg2 with robust identification and redshift measured by a combination of principal component eigenspectra. The number of quasars with z > 2.15 (117,668) is ~5 times greater than the number of z > 2.15 quasars known prior to BOSS. Redshifts and FWHMs are provided for the strongest emission lines (C IV, C III, Mg II). The catalog identifies 16,461 broad absorption line (BAL) quasars and gives their characteristics. For each object, the catalog presents five-band (u, g, r, i, z) CCD-based photometry with typical accuracy of 0.03 mag and information on the optical morphology and selection method. 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 cover the wavelength region 3,600 - 10,500 Angstrom at a spectral resolution in the range 1,300 < R < 2,500; the spectra can be retrieved from the SDSS Catalog Archive Server at http://www.sdss3.org/dr10/data_access/. In their paper, the authors also provided a supplemental list of an additional 2,376 quasars that have were identified among the galaxy targets of the SDSS-III/BOSS: these are not included in the present table.

In SDSS-III, all fluxes in the 5 SDSS bands (u, g, r, i and z) are expressed in terms of "nanomaggies" (nMgy), which are a convenient linear unit. These quantities are related to standard AB magnitudes thus: an object with a flux F given in nMgy has a Pogson magnitude (on the AB scale) m=[22.5 mag] - 2.5*log10(F). A flux of 1 Mgy is therefore close to 3631 Jy, and 1 nMgy = ~3.631 uJy (microJy).


Catalog Bibcode

2014A&A...563A..54P

References

The Sloan Digital Sky Survey: tenth data release.
    Paris I., Petitjean P., Aubourg E., Ross N.P., Myers A.D., Strblyanska A.,
    Bailey S., Hall P.B., Strauss M.A., Anderson S.F., Bizyaev D., Borde A.,
    Brinkmann J., Bovy J., Brandt W.N., Brewington H., Browstein J.R.,
    Cook B.A., Ebelke G., Fan X., Filiz Ak N., Finley H., Font-Ribera A.,
    Ge J., Hamann F., Ho S., Jiang L., Kinemuchi K., Malanushenko E.,
    Malanushenko V., Marchante M., McGreer I.D., McMahon R.G., Miralda-Escude
    J., Muna D., Noterdaeme P., Oravetz D., Palanque-Delabrouille N., Pan K.,
    Perez-Fournon I., Pieri M., Riffel R., Schlegel D.J., Schneider D.P.,
    Simmons A., Viel M., Weaver B.A., Wood-Vasey W.M., Yeche C., York D.G.
   <Astron. Astrophys. 563, A54 (2014)>
   =2014A&A...563A..54P
   =2014yCat.7270....0P

Provenance

This table was created by the HEASARC in May 2014 based on CDS Catalog VII/270 file dr10q.dat.

Parameters

Name
The SDSS DR10 object designation, given by the format SDSS Jhhmmss.ss+ddmmss.s. The coordinates in the object name follow IAU convention and are truncated, not rounded.

RA
The Right Ascension of the quasar in the selected equinox. This was given in J2000.0 decimal degrees to a precision of 10-6 degrees in the original table. The astrometry is from SDSS-DR10 (see Ahn et al. 2012, ApJS, 203, 21).

Dec
The Declination of the quasar in the selected equinox. This was given in J2000.0 decimal degrees to a precision of 10-6 degrees in the original table. The astrometry is from SDSS-DR10 (see Ahn et al. 2012, ApJS, 203, 21).

LII
The Galactic Longitude of the quasar.

BII
The Galactic Latitude of the quasar.

Thing_ID
The 64-bit integer that uniquely describes the objects that are listed in the SDSS (photometric and spectroscopic) catalogs (THING_ID).

Spect_Plate_Number
The SDSS spectroscopic plate number of the observation. This is one of 3 pieces of information about the spectroscopic observation (spectroscopic plate number, modified Julian Date, and spectroscopic fiber number) that were used to determine the characteristics of the spectrum. These three numbers are unique for each spectrum, and can be used to retrieve the digital spectra from the public SDSS database. When an object has been observed several times, the authors selected the best quality spectrum as defined by the SDSS pipeline (Bolton et al. 2012, AJ, 144, 144), i.e. with SPECPRIMARY = 1.

Spect_Date
The SDSS spectroscopic date of the observation. This is one of 3 pieces of information about the spectroscopic observation (spectroscopic plate number, modified Julian Date - the HEASARC xTime web tool can be used to find the MJD corresponding to this YYYY-MM-DD date - and spectroscopic fiber number) that were used to determine the characteristics of the spectrum. These three numbers are unique for each spectrum, and can be used to retrieve the digital spectra from the public SDSS database. When an object has been observed several times, the authors selected the best quality spectrum as defined by the SDSS pipeline (Bolton et al. 2012, AJ, 144, 144), i.e. with SPECPRIMARY = 1.

Spect_Fiber_Number
The SDSS fiber number of the observation. This is one of 3 pieces of information about the spectroscopic observation (spectroscopic plate number, modified Julian Date, and spectroscopic fiber number) that were used to determine the characteristics of the spectrum. These three numbers are unique for each spectrum, and can be used to retrieve the digital spectra from the public SDSS database. When an object has been observed several times, the authors selected the best quality spectrum as defined by the SDSS pipeline (Bolton et al. 2012, AJ, 144, 144), I.e. with SPECPRIMARY = 1.

VI_Redshift
The redshift of the quasar obtained from the visual inspection, Z_VI (see Sections 3.1 and 4.2.2 of the reference paper for more details).

Pipeline_Redshift
The redshift of the quasar from the SDSS BOSS pipeline (Bolton et al. 2012, AJ, 144, 144).

Pipeline_Redshift_Error
The error in the SDSS pipeline redshift of the quasar.

Pipeline_Redshift_Flag
The ZWARNING flag from the pipeline. ZWARNING > 0 indicates uncertain results in the redshift-fitting code (Bolton et al. 2012, AJ, 144, 144). This 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
  

PCA_Redshift
An automatic redshift estimate Z_PCA for the quasar which uses a linear combination of four principal components (see Section 4 of Paris et al. 2012, A&A, 548, A66 for details). When the velocity difference between the automatic PCA and visual inspection redshift estimates is larger than 3000 km s-1, this PCA redshift is set to null (-1 in the original table).

PCA_Redshift_Error
The error in the automatic PCA redshift estimate for the quasar. If the PCA redshift is set to null, the associated error is also set to null (-1 in the original table).

PCA_Continuum_Quality
An estimator of the PCA continuum quality (between 0 and 1) as given in Eq. (11) of Paris et al. (2011, A&A, 530, A50).

C_IV_Redshift
The redshift of the quasar measured from the C IV emission line from a linear combination of five principal components (see Paris et al. 2012, A&A, 548, A66). The line redshift is estimated using the maximum of each emission line, contrary to Z_PCA (the pca_redshift parameter) that is a global estimate using all the information available in a given spectrum.

C_III_Redshift
The redshift of the quasar measured from the the C III] emission line complex from a linear combination of five principal components (see Paris et al. 2012, A&A, 548, A66). The line redshift is estimated using the maximum of each emission line, contrary to Z_PCA (the pca_redshift parameter) that is a global estimate using all the information available in a given spectrum.

Mg_II_Redshift
The redshift of the quasar measured from the Mg II emission line from a linear combination of five principal components (see Paris et al. 2012, A&A, 548, A66). The line redshift is estimated using the maximum of each emission line, contrary to Z_PCA (the pca_redshift parameter) that is a global estimate using all the information available in a given spectrum.

Morphology_Flag
The morphological information flag for the quasar: objects classified as point sources by the SDSS photometric pipeline have SDSS_MORPHO = 0 while extended quasars have SDSS_MORPHO = 1. The vast majority of the quasars included in the present catalog are unresolved (SDSS_MORPHO = 0) as it is a requirement of the main quasar target selection (Ross et al. 2012, ApJS, 199, 3).

Boss_TS_Flag
The BOSS target selection flag for the quasar. The main target selection information is tracked with the BOSS_TARGET1 flag bits (19; see Table 2 in Ross et al. 2012, ApJS, 199, 3 for a full description).

Anc_TS_Flag_1
The ancillary target selection flag 1 for the quasar. Ancillary program target selection is tracked with the ANCILLARY_TARGET1 (20) and ANCILLARY_TARGET2 (21) flag bits. The bit values and the corresponding program names are listed in Dawson et al. (2013, AJ, 145, 10) and Appendix B of the reference paper.

Anc_TS_Flag_2
The ancillary target selection flag 2 for the quasar. Ancillary program target selection is tracked with the ANCILLARY_TARGET1 (20) and ANCILLARY_TARGET2 (21) flag bits. The bit values and the corresponding program names are listed in Dawson et al. (2013, AJ, 145, 10) and Appendix B of the reference paper.

SDSS_Dr7_Quasar_Flag
A quasar previously known from the SDSS-DR7 quasar catalog (Schneider et al. 2010, AJ, 139, 2360, CDS Cat. VII/260) has a value equal to 1 for this parameter, and is set to 0 otherwise. During Year 1 and 2, all SDSS-DR7 quasars with z >= 2.15 were re-observed. After Year 2, all SDSS-DR7 quasars with z >= 1.8 have been re-observed.

SDSS_Dr7_Plate_Number
The SDSS-DR7 spectroscopic plate number for the quasar.

SDSS_Dr7_Spect_Date
The date when the SDSS-DR7 spectroscopic data were obtained.

SDSS_Dr7_Fiber_Number
The SDSS-DR7 spectroscopic fiber number for the quasar.

Uniform_Sample_Flag
The uniform sample flag value for the quasar. The authors provide a uniform flag in order to identify a homogeneously selected sample of quasars. Although the CORE sample has been designed to have a well understood, uniform, and reproducible selection function, its definition varied over the first year of the survey. Thus, the nominal CORE quasars are not a uniformly-selected sample. Areas within which all the algorithms used in the quasar target selection are uniform are called "Chunks". The definition of each of them can be found in Ross et al. (2012, ApJS, 199, 3). After Chunk 12, CORE targets were selected with the XDQSO technique alone (Bovy et al. 2011, ApJ, 729, 141). These objects have uniform = 1. Quasars in this catalog with uniform = 2 are objects that would have been selected by XDQSO if it had been the CORE algorithm prior to Chunk 12. Objects with uniform = 2 are reasonably complete to what XDQSO would have selected, even prior to Chunk 12. But, as DR10Q only contains information about spectroscopically confirmed quasars, not about all targets, care must be taken to create a statistical sample from the uniform flag. See, e.g., the discussion regarding the creation of a statistical sample for clustering measurements in White et al. (2012, MNRAS, 424, 933). Quasars with uniform = 0 are not homogeneously selected CORE targets.

Spectral_Index
The spectral index of the quasar, alpha. The continuum is approximated by a power-law, fcont ~ nualpha, and is computed in emission line free regions: 1450 - 1500 A, 1700 - 1850 A and 1950 - 2750 A in the quasar rest frame.

SNR_Overall
The median signal-to-noise ratio (SNR) per pixel for the quasar, computed over the whole spectrum.

SNR_1700_Angstrom
The median SNR per pixel for the quasar, computed over the window 1650 - 1750 A, in the quasar rest frame. If the wavelength range is not covered by the BOSS spectrum, the value is set to null (-1 in the original table).

SNR_3000_Angstrom
The median SNR per pixel for the quasar, computed over the window 2950 - 3050 A, in the quasar rest frame. If the wavelength range is not covered by the BOSS spectrum, the value is set to null (-1 in the original table).

SNR_5150_Angstrom
The median SNR per pixel for the quasar, computed over the window 5100 - 5250 A, in the quasar rest frame. If the wavelength range is not covered by the BOSS spectrum, the value is set to null (-1 in the original table).

C_IV_FWHM
The FWHM (km s-1) of the C IV emission line. If the emission line is not in the spectrum, the FWHM is set to null (-1 in the original table).

C_IV_Blue_Hwhm
The blue half width at half-maximum (HWHM, in km s-1: the sum of the blue and red HWHMs equals the FWHM) of the C IV emission line. If the emission line is not in the spectrum, the blue HWHM is set to null (-1 in the original table).

C_IV_Red_Hwhm
The red half width at half-maximum (HWHM, in km s-1: the sum of the blue and red HWHMs equals the FWHM) of the C IV emission line. If the emission line is not in the spectrum, the blue HWHM is set to null (-1 in the original table).

C_IV_Amplitude
The amplitude of the C IV emission line in units of the median rms pixel noise (see Section 4 of Paris et al. 2012, A&A, 548, A66).

C_IV_Rf_EW
The rest frame equivalent width in Angstrom of the C IV emission line. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table).

C_IV_Rf_Ew_Error
The uncertainty in the rest frame equivalent width in Angstrom of the C IV emission line. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table).

C_III_FWHM
The FWHM in km s-1 of the C III] emission line complex. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table). It is well known that C III] 1909A is blended with Si III] 1892A and to a lesser extent with Al III] 1857A. The authors do not attempt to deblend these lines. Therefore the redshift and red HWHM derived for this blend correspond to C III] 1909A. The blue HWHM is obviously affected by the blend.

C_III_Blue_Hwhm
The blue HWHM in km s-1 of the C III] emission line complex. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table). It is well known that C III] 1909A is blended with Si III] 1892A and to a lesser extent with Al III] 1857A. The authors do not attempt to deblend these lines. Therefore the redshift and red HWHM derived for this blend correspond to C III] 1909A. The blue HWHM is obviously affected by the blend.

C_III_Red_Hwhm
The red HWHM in km s-1 of the C III] emission line complex. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table). It is well known that C III] 1909A is blended with Si III] 1892A and to a lesser extent with Al III] 1857A. The authors do not attempt to deblend these lines. Therefore the redshift and red HWHM derived for this blend correspond to C III] 1909A. The blue HWHM is obviously affected by the blend.

C_III_Amplitude
The amplitude of the C III] emission line complex in units of the median rms pixel noise (see Section 4 of Paris et al. 2012, A&A, 548, A66).

C_III_Rf_EW
The rest frame equivalent width in Angstrom of the C III] emission line complex. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table).

C_III_Rf_Ew_Error
The uncertainty in the rest frame equivalent width in Angstrom of the C III] emission line complex. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table).

Mg_II_FWHM
The FWHM in km s-1 of the Mg II emission line. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table.

Mg_II_Blue_Hwhm
The blue HWHM in km s-1 of the Mg II emission line. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table.

Mg_II_Red_Hwhm
The red HWHM in km s-1 of the Mg II emission line. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table.

Mg_II_Amplitude
The amplitude of the Mg II emission line in units of the median rms pixel noise (see Section 4 of Paris et al. 2012, A&A, 548, A66).

Mg_II_Rf_EW
The rest frame equivalent width in Angstrom of the Mg II emission line. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table). The authors do not correct for the Fe II emission.

Mg_II_Rf_Ew_Error
The uncertainty in the rest frame equivalent width in Angstrom of the Mg II emission line. If the emission line is not in the spectrum, this quantity is set to null (-1 in the original table).

Bal_Vi_Flag
The BAL flag from the visual inspection, BAL_FLAG_VI. If a BAL feature was identified in the course of the visual inspection, BAL_FLAG_VI is set to 1, 0 otherwise. Note that BAL quasars are flagged during the visual inspection at any redshift.

C_IV_Trough_BI
The balnicity index (BI; Weymann et al. 1991, ApJ, 373, 23) for C IV troughs, and their errors, expressed in km s-1. See he definition in Section 5 of Paris et al. (2012, A&A, 548, A66). The Balnicity index is measured for quasars with z > 1.57 only so that the trough enters into the BOSS wavelength region. If the BAL flag from the visual inspection is set to 1 and the BI is equal to 0, this means either that there is no C IV trough (but a trough is seen in another transition) or that the trough seen during the visual inspection does not meet the formal requirement of the BAL definition. In cases with bad fits to the continuum, the balnicity index and its error are set to null (-1 in the original table.

C_IV_Trough_Bi_Error
The error in the BI of the C IV trough, in km s-1.

C_IV_Trough_Ai
The absorption index AI for the C IV troughs expressed in km s-1. See the definition in Section 5 of Paris et al. (2012, A&A, 548, A66). In cases with bad continuum fits, the absorption index and its error are set to null (-1 in the original table.

C_IV_Trough_Ai_Error
The error in the AI of the C IV trough, in km s-1.

C_IV_Trough_Ai_Chi2
Following Trump et al. (2006, ApJS, 165, 1), the authors calculate the reduced chi-squared which they call Chi2trough for each C IV trough from Equation (3) in Paris et al. (2012, A&A, 548, A66). They require that troughs have Chi2trough > 10 to be considered as true troughs.

C_IV_Troughs_2k_Num
The number of C IV troughs of width greater than 2000 km/s.

C_IV_Troughs_2k_Min_Vel
The minimum velocity limit of the velocity range in which C IV troughs of width larger than 2000 km s-1 and reaching at least 10% below the continuum are to be found. Velocities are positive bluewards and the zero of the scale is at the visual inspection redshift, Z_VI. So, if there are multiple troughs, this goes from one end of the first one to the other end of the last one.

C_IV_Troughs_2k_Max_Vel
The maximum velocity limit of the velocity range in which C IV troughs of width larger than 2000 km s-1 and reaching at least 10% below the continuum are to be found. Velocities are positive bluewards and the zero of the scale is at the visual inspection redshift, Z_VI. So, if there are multiple troughs, this goes from one end of the first one to the other end of the last one.

C_IV_Troughs_450_Num
The number of C IV troughs of width greater than 450 km/s.

C_IV_Troughs_450_Min_Vel
The minimum velocity limit of the velocity range in which C IV troughs of width larger than 450 km s-1 and reaching at least 10% below the continuum are to be found. Velocities are positive bluewards and the zero of the scale is at the visual inspection redshift, Z_VI. So, if there are multiple troughs, this goes from one end of the first one to the other end of the last one.

C_IV_Troughs_450_Max_Vel
The maximum velocity limit of the velocity range in which C IV troughs of width larger than 450 km s-1 and reaching at least 10% below the continuum are to be found. Velocities are positive bluewards and the zero of the scale is at the visual inspection redshift, Z_VI. So, if there are multiple troughs, this goes from one end of the first one to the other end of the last one.

Si_IV_Trough_Rf_EW
The rest frame equivalent width in A of Si IV troughs detected in BAL quasars with BI > 500 km s-1 and SNR_1700 > 5. They are set to 0 otherwise or in cases where no trough is detected and to -1 if the continuum is not reliable.

C_IV_Trough_Rf_EW
The rest frame equivalent width in A of C IV troughs detected in BAL quasars with BI > 500 km s-1 and SNR_1700 > 5. They are set to 0 otherwise or in cases where no trough is detected and to -1 if the continuum is not reliable.

Al_III_Trough_Rf_EW
The rest frame equivalent width in A of Al III troughs detected in BAL quasars with BI > 500 km s-1 and SNR_1700 > 5. They are set to 0 otherwise or in cases where no trough is detected and to -1 if the continuum is not reliable.

Imaging_Run_Number
The SDSS Imaging Run number of the photometric observation used in the catalog.

Imaging_Date
The date of the SDSS photometric observation used in the catalog.

Phot_Proc_Rerun_Number
The SDSS photometric processing rerun number (see Stoughton et al. 2002, AJ, 123, 485 for a description of this parameter)

Camera_Column_Number
The SDSS camera column number containing the image of the object (see Stoughton et al. 2002, AJ, 123, 485 for a description of this parameter).

Field_Number
The SDSS field number of the run containing the object (see Stoughton et al. 2002, AJ, 123, 485 for a description of this parameter)

Object_Number
The SDSS object identification number (see Stoughton et al. 2002, AJ, 123, 485 for a description of this parameter).

Flux_U_Band
The SDSS-DR10 PSF flux of the quasar In the u band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_G_Band
The SDSS-DR10 PSF flux of the quasar in the g band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_R_Band
The SDSS-DR10 PSF flux of the quasar in the r band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_I_Band
The SDSS-DR10 PSF flux of the quasar in the i band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_Z_Band
The SDSS-DR10 PSF flux of the quasar in the z band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_U_Band_IV
The inverse variance of the SDSS-DR10 PSF flux in the u band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_G_Band_IV
The inverse variance of the SDSS-DR10 PSF flux in the g band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_R_Band_IV
The inverse variance of the SDSS-DR10 PSF flux in the r band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_I_Band_IV
The inverse variance of the SDSS-DR10 PSF flux in the i band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Flux_Z_Band_IV
The inverse variance of the SDSS-DR10 PSF flux in the z band in nanomaggies (see Overview) and not corrected for Galactic extinction.

Umag
The SDSS-DR10 PSF AB magnitude of the quasar in the u band (Lupton et al. 1999, AJ, 118, 1406) and not corrected for Galactic extinction.

Umag_Error
The error in the SDSS-DR10 PSF AB magnitude in the u band.

Gmag
The SDSS-DR10 PSF AB magnitude of the quasar in the g band (Lupton et al. 1999, AJ, 118, 1406) and not corrected for Galactic extinction.

Gmag_Error
The error in the SDSS-DR10 PSF AB magnitude in the g band.

Rmag
The SDSS-DR10 PSF AB magnitude of the quasar in the r band (Lupton et al. 1999, AJ, 118, 1406) and not corrected for Galactic extinction.

Rmag_Error
The error in the SDSS-DR10 PSF AB magnitude in the r band.

Imag
The SDSS-DR10 PSF AB magnitude of the quasar in the i band (Lupton et al. 1999, AJ, 118, 1406) and not corrected for Galactic extinction

Imag_Error
The error in the SDSS-DR10 PSF AB magnitude in the i band.

Zmag
The SDSS-DR10 PSF AB magnitude of the quasar in the z band (Lupton et al. 1999, AJ, 118, 1406) and not corrected for Galactic extinction.

Zmag_Error
The error in the SDSS-DR10 PSF AB magnitude in the z band.

Target_Flux_U_Band
The DR8 PSF flux of the quasar (not corrected for Galactic extinction), expressed in nanomaggies, in the u band. This photometry is the one that was used for the main quasar target selection (Ross et al. 2012, ApJS, 199, 3).

Target_Flux_G_Band
The DR8 PSF flux of the quasar (not corrected for Galactic extinction), expressed in nanomaggies, in the g band. This photometry is the one that was used for the main quasar target selection (Ross et al. 2012, ApJS, 199, 3).

Target_Flux_R_Band
The DR8 PSF flux of the quasar (not corrected for Galactic extinction), expressed in nanomaggies, in the r band. This photometry is the one that was used for the main quasar target selection (Ross et al. 2012, ApJS, 199, 3).

Target_Flux_I_Band
The DR8 PSF flux of the quasar (not corrected for Galactic extinction), expressed in nanomaggies, in the i band. This photometry is the one that was used for the main quasar target selection (Ross et al. 2012, ApJS, 199, 3).

Target_Flux_Z_Band
The DR8 PSF flux of the quasar (not corrected for Galactic extinction), expressed in nanomaggies, in the z band. This photometry is the one that was used for the main quasar target selection (Ross et al. 2012, ApJS, 199, 3).

Abs_Imag
The absolute magnitude of the quasar in the i band at z = 2 calculated after correction for Galactic extinction and assuming H0 = 70 km s-1 Mpc-1, OmegaM = 0.3, OmegaLambda = 0.7, and a power-law (frequency) continuum index of -0.5. The K-correction is computed using Table 4 from Richards et al. (2006, AJ, 131, 2766). The authors use the SDSS primary photometry to compute this value.

GI_Color_Offset
The Delta(g-i) color of the quasar, which is the difference in the Galactic extinction corrected (g-i) for the quasar and that of the mean of the quasars at that redshift. If Delta(g-) is not defined for the quasar, which occurs for objects at either z < 0.12 or z > 5.12; the column will contain a null (-999.999 in the original table).

Gal_Ext_U_Band
The Galactic extinction towards the quasar in the u band based on the maps of Schlegel et al. (1998, ApJ, 500, 525). The quasar target selection was done using these maps.

Gal_Ext_G_Band
The Galactic extinction towards the quasar in the g band based on the maps of Schlegel et al. (1998, ApJ, 500, 525). The quasar target selection was done using these maps.

Gal_Ext_R_Band
The Galactic extinction towards the quasar in the r band based on the maps of Schlegel et al. (1998, ApJ, 500, 525). The quasar target selection was done using these maps.

Gal_Ext_I_Band
The Galactic extinction towards the quasar in the i band based on the maps of Schlegel et al. (1998, ApJ, 500, 525). The quasar target selection was done using these maps.

Gal_Ext_Z_Band
The Galactic extinction towards the quasar in the z band based on the maps of Schlegel et al. (1998, ApJ, 500, 525). The quasar target selection was done using these maps.

SF_Gal_Ext_U_Band
The Galactic extinction towards the quasar in the u band based on the maps of Schlafly and Finkbeiner (2011, ApJ, 737, 103).

SF_Gal_Ext_G_Band
The Galactic extinction towards the quasar in the g band based on the maps of Schlafly and Finkbeiner (2011, ApJ, 737, 103).

SF_Gal_Ext_R_Band
The Galactic extinction towards the quasar in the r band based on the maps of Schlafly and Finkbeiner (2011, ApJ, 737, 103).

SF_Gal_Ext_I_Band
The Galactic extinction towards the quasar in the i band based on the maps of Schlafly and Finkbeiner (2011, ApJ, 737, 103).

SF_Gal_Ext_Z_Band
The Galactic extinction towards the quasar in the z band based on the maps of Schlafly and Finkbeiner (2011, ApJ, 737, 103).

Log_NH_Gal
The logarithm of the Galactic neutral hydrogen column density along the line of sight to the quasar, in atoms cm-2. These values were estimated via interpolation of the 21-cm data from Stark et al. (1992, ApJS, 79, 77), using the COLDEN software provided by the Chandra X-ray Center. Errors associated with the interpolation are expected to be typically less than ~ 1 x 1020 cm-2 (e.g., see Section 5 of Elvis et al. 1994, ApJS, 95, 413).

RASS_Log_Count_Rate
The logarithm of the vignetting-corrected count rate (photons s-1) in the broad energy band (0.1 - 2.4 keV) from the ROSAT All-Sky Survey (RASS) Faint Source Catalog (Voges et al. 2000, IAUC 7432) and the RASS Bright Source Catalog (Voges et al. 1999, A&A, 349, 389). The matching radius was set to 30 arcsecond (see Sect. 4.5.6 of the reference paper).

RASS_SNR
The signal-to-noise ratio of the RASS measurement.

SDSS_RASS_Offset
The angular separation between the SDSS-DR10 and the ROSAT All-Sky Survey locations of the quasar (in arcseconds).

Number_XMM_Detections
The number of XMM-Newton matches in a 5-arcsecond radius around the SDSS-DR10 quasar position.

SB_Lx
The soft (0.5-2.0 keV) X-ray flux from the XMM-Newton matching to the SDSS quasar, expressed in erg cm-2 s-1 (in case of several observations, the one with the longest exposure time is used to compute the flux), was used to calculate the corresponding X-ray luminosity in this band, expressed in erg s-1. This value is computed using the visual inspection redshift (Z_VI) and H0 = 70 km s-1 Mpc-1, Omegam = 0.3, OmegaLamda = 0.7.

HB_Lx_Limit
This flag is set to '<' if the corresponding parameter value is an upper limit or unreliable not a confirmed detection.

HB_Lx
The hard (2-12 keV) X-ray flux from the XMM-Newton matching to the SDSS quasar, expressed in erg cm-2 s-1 (in case of several observations, the one with the longest exposure time is used to compute the flux), was used to calculate the corresponding X-ray luminosity in this band, expressed in erg s-1. This value is computed using the visual inspection redshift (Z_VI) and H0 = 70 km s-1 Mpc-1, Omegam = 0.3, OmegaLamda = 0.7.

SDSS_XMM_Offset
The angular separation between the SDSS-DR10 and the XMM-Newton locations of the quasar (in arcseconds).

GALEX_Match_Flag
This flag parameter (GALEX_MATCHED) is set to 1 if the SDSS-DR10 quasar has a matched with a GALEX source, else is set to 0.

GALEX_FUV_Flux
The flux of the GALEX counterpart, aperture-photometered from the original GALEX images, in the FUV band. The fluxes are expressed in nanomaggies.

GALEX_FUV_Flux_IV
The inverse variance of the GALEX FUV flux.

GALEX_NUV_Flux
The flux of the GALEX counterpart, aperture-photometered from the original GALEX images, in the NUV band. The fluxes are expressed in nanomaggies.

GALEX_NUV_Flux_IV
The inverse variance of the GALEX NUV flux.

Jmag
The J magnitude from the Two Micron All Sky Survey All-Sky (2MASS) Data Release Point Source Catalog (Cutri et al. 2003, CDS Cat. II/246) using a matching radius of 2.0 arcseconds (see Section 4.5.3 of the reference paper). A non-detection by 2MASS is indicated by a null value (0.000 in the original table). Note that the 2MASS measurements are Vega-based, not AB, magnitudes.

Jmag_Error
The error in the 2MASS J magnitude.

Jmag_SNR
The signal-to-noise ratio of the 2MASS J-band measurement.

Jmag_Flag
The 2MASS jr_d flag that gives the meaning of peculiar values of the corresponding band magnitude and its error (see http://www.ipac.caltech.edu/2mass/releases/ allsky/doc/explsup.html).

Hmag
The H magnitude from the Two Micron All Sky Survey All-Sky (2MASS) Data Release Point Source Catalog (Cutri et al. 2003, CDS Cat. II/246) using a matching radius of 2.0 arcseconds (see Section 4.5.3 of the reference paper). A non-detection by 2MASS is indicated by a null value (0.000 in the original table). Note that the 2MASS measurements are Vega-based, not AB, magnitudes.

Hmag_Error
The error in the 2MASS H magnitude.

Hmag_SNR
The signal-to-noise ratio of the 2MASS H-band measurement.

Hmag_Flag
The 2MASS jr_d flag that gives the meaning of peculiar values of the corresponding band magnitude and its error (see http://www.ipac.caltech.edu/2mass/releases/ allsky/doc/explsup.html).

Kmag
The K magnitude from the Two Micron All Sky Survey All-Sky (2MASS) Data Release Point Source Catalog (Cutri et al. 2003, CDS Cat. II/246) using a matching radius of 2.0 arcseconds (see Section 4.5.3 of the reference paper). A non-detection by 2MASS is indicated by a null value (0.000 in the original table). Note that the 2MASS measurements are Vega-based, not AB, magnitudes.

Kmag_Error
The error in the 2MASS K magnitude.

Kmag_SNR
The signal-to-noise ratio of the 2MASS K-band measurement.

Kmag_Flag
The 2MASS jr_d flag that gives the meaning of peculiar values of the corresponding band magnitude and its error (see http://www.ipac.caltech.edu/2mass/releases/ allsky/doc/explsup.html).

SDSS_2MASS_Offset
The angular separation between the SDSS and 2MASS positions of the quasar (in arcseconds).

WISE_W1_Mag
The w1 (3.4 um) magnitude Of the match to the SDSS-DR10 quasar from the Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010, AJ, 140, 1868) All-Sky Data Release Point Source Catalog using a matching radius of 2 arcseconds.

WISE_W1_Mag_Error
The error in the WISE w1 magnitude of the match to the SDSS-DR10 quasar.

WISE_W1_Mag_SNR
The signal-to-noise ratio of the WISE w1-band detection.

WISE_W1_Mag_Chi2
The chi-squared of the WISE w1-band detection.

WISE_W2_Mag
The w2 (4.6 um) magnitude of the match to the SDSS-DR10 quasar from the Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010, AJ, 140, 1868) All-Sky Data Release Point Source Catalog using a matching radius of 2 arcseconds.

WISE_W2_Mag_Error
The error in the WISE w2 magnitude of the match to the SDSS-DR10 quasar.

WISE_W2_Mag_SNR
The signal-to-noise ratio of the WISE w2-band detection.

WISE_W2_Mag_Chi2
The chi-squared of the WISE w2-band detection.

WISE_W3_Mag
The w3 (12 um) magnitude of the match to the SDSS-DR10 quasar from the Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010, AJ, 140, 1868) All-Sky Data Release Point Source Catalog using a matching radius of 2 arcseconds.

WISE_W3_Mag_Error
The error in the WISE w3 magnitude of the match to the SDSS-DR10 quasar.

WISE_W3_Mag_SNR
The signal-to-noise ratio of the WISE w3-band detection.

WISE_W3_Mag_Chi2
The chi-squared of the WISE w3-band detection.

WISE_W4_Mag
The w4 (22 um) magnitude of the match to the SDSS-DR10 quasar from the Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010, AJ, 140, 1868) All-Sky Data Release Point Source Catalog using a matching radius of 2 arcseconds.

WISE_W4_Mag_Error
The error in the WISE w4 magnitude of the match to the SDSS-DR10 quasar.

WISE_W4_Mag_SNR
The signal-to-noise ratio of the WISE w4-band detection.

WISE_CC_Flag
The WISE contamination and confusion flag for the source.

SDSS_Wise_Offset
The angular separation between the SDSS-DR10 and WISE positions of the quasar (in arcseconds).

UKIDSS_Match_Flag
If an SDSS-DR10 quasar matches UKIDSS aperture-photometric data, this parameter is set to 1, it is set to 0 otherwise.

First_Match_Flag
If there is a source in the FIRST radio catalog (version February 2012) within 2.0 arcseconds of the quasar position, this flag is set to 1, O if not. If the quasar lies outside of the FIRST footprint, it is set to null (-1 in the original table).

Flux_20_cm
The FIRST peak flux density of the quasar at 20 cm, in mJy.

SNR_20_cm
The signal-to-noise ratio of the FIRST 20-cm detection of the quasar.

SDSS_FIRST_Offset
The angular separation between the SDSS and FIRST positions of the quasar (in arcseconds).


Contact Person

Questions regarding the SDSSQUASAR database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 22-May-2014