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EINOPSLGAL - Einstein Survey of Optically Selected Galaxies

HEASARC
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Overview

The Einstein Survey of Optically Selected Galaxies contains the results of a complete Einstein Imaging Proportional Counter (IPC) X-ray survey of optically-selected galaxies from the Shapley-Ames (S-A) Catalog (CDS Catalog <VII/112>), the Uppsala General Catalog (UGC, CDS Catalog <VII/26>) and the European Southern Observatory (ESO) Catalog (CDS Catalog <VII/115>). Well-defined optical criteria were used to select the galaxies, and X-ray fluxes were measured at the optically-defined positions. The result is a comprehensive list of X-ray detection and upper limit measurements for 1018 galaxies. Of these, 827 galaxies have either independent distance estimates or radial velocities. Associated optical, redshift, and distance data have been assembled for these galaxies, and their distances come from a combination of directly predicted distances and those predicted from the Faber-Burstein Great Attractor/Virgocentric infall model. The accuracy of the X-ray fluxes has been checked in three different ways; all are consistent with the derived X-ray fluxes being of <= 0.1 dex accuracy. In particular, there is agreement with previously published X-ray fluxes for galaxies in common with a 1991 study by Roberts et al. (1991ApJS...75..751R) and a 1992 study by Fabbiano et al. (1992ApJS...80..531F, also available at the HEASARC as a database table called EINGALCAT).

Catalog Bibcode

1997ApJS..111..163B

References

An Einstein X-ray survey of optically selected galaxies. I. Data
     Burstein D., Jones C., Forman W., Marston A.P., Marzke R.O.
    <Astrophys. J. Suppl. Ser. 111, 163 (1997)>
    =1997ApJS..111..163B

Provenance

This database was created at the HEASARC in May 2002 based on the ADC/CDS Catalog J/ApJS/111/163 and is derived from Tables 5, 6, 7, 12, 13, and 14 of the published paper.

HEASARC Changes

The HEASARC has made a small number of changes to the data as written in the original tables supplied to the CDS by the authors, so as to make this database table more in conformance with its standard practices:

(i) We have combined data from three separate pairs of CDS tables (for ESO, UGC and S-A galaxies, respectively) into one database table. To identify from which original table pair any given entry originates, we created a new parameter galaxy_sample with self-explanatory values of ESO, UGC and S-A. Notice that some of the parameters, such as t_type and bmag, can have somewhat different meanings depending on which sample they come from: carefully check the help section describing the various parameters for a discussion of these subtleties.

(ii) The naming convention used for galaxies in the tables in their original forms was condensed and non-standard, and we have thus converted them to more standard names which, for example, are recognized by the CDS Simbad: thus, the prefix 'N' has been replaced by 'NGC','I' by 'IC', 'U' by 'UGC', and 'E' by 'ESO'. For ESO galaxies we have also removed the embedded 'G' and 'IG' characters: thus, the original name 'E116-IG07' is rendered in this HEASARC table as 'ESO 116-07'.

(iii) In a few cases, we have used different units for parameters than were used in the original tables: arcminutes rather than tenths of arcminutes for the angular diameter (the log_d parameter), and counts per second rather than counts per kilosecond for the X-ray count rate and error (count_rate and count_rate_error parameters, respectively).


Parameters

Name
The name of the galaxy. The naming convention used for galaxies in the tables in their original forms was condensed and non-standard, and we have thus converted them to more standard names which, for example, are recognized by the CDS Simbad: thus, the prefix 'N' has been replaced by 'NGC','I' by IC', 'U' by 'UGC', and 'E' by 'ESO'. For ESO galaxies we have also removed the embedded 'G' and 'IG' characters: thus, the original name 'E116-IG07' is rendered in this HEASARC table as 'ESO 116-07'.

Bmag
The apparent B Magnitude of the galaxy. For Shapley-Ames galaxies (galaxy_sample = 'S-A'), this is the BT magnitude or otherwise mB as given in the computer version of RC2 (de Vaucouleurs et al., 1976, CDS Cat. <VII/112>, for UGC galaxies (galaxy_sample = 'UGC'), if bmag <= 15.7, this comes from Zwicky (1961-1968, CDS Cat. <VII/49>) via Huchra (1976AJ.....81..952H) corrections, otherwise it is just a rough estimate (accuracy 0.5 - 1.0 mag) by Nilson (1973, CDS Cat. <VII/26>), and for ESO galaxies (galaxy_sample = 'ESO'), this is as given in the ESO-LV catalog (Lauberts & Valentijn, 1989, CDS Cat. <VII/115>), or 0.00 if no magnitude given.

Log_D
The logarithm of the angular diameter in the B band, in arcminutes. For Shapley-Ames galaxies (galaxy_sample = 'S-A'), this is the logarithm of the RC2 observed B mag diameter, log D25, for UGC galaxies (galaxy_sample = 'UGC'), this is the logarithm of the UGC Bmag diameter, and for ESO galaxies (galaxy_sample = 'ESO'), this is the logarithm of the ESO-LV Bmag diameter at the 25th mag isophote, and is set to -2.10 if no diameter is given.

T_Type
The morphological type code or Hubble numerical type for the galaxy. For Shapley-Ames galaxies (galaxy_sample = 'S-A'), this is the RC2 numerical code for galaxy morphological type, e.g., -5 = E, 0 = S0/a, 5 = Sc, 10 = Im, with the Burstein revision that I0 = -7 (not 0 as in RC2), while for UGC and ESO galaxies (galaxy_sample = 'UGC' and 'ESO', respectively), this is the the hierarchical numerical typing system for morphological types as developed by Burstein. The abbreviated system for the UGC and ESO catalogs is as follows:

      Burstein Code Number   Classification

                   1          E and E/S0
                  10          All S0
                  11          All S0/a
                  12          All Sa
                  13          All Sa/b
                  14          All Sb
                  15          All Sb/Sc
                  16          All Sc
                  17          All Sc/Sd
                  18          All Sd
                  19          All Sd/Irr
                  20          All Irr
                  30          All non-divided classified types
                  40          Dwarf galaxies
                  50          Compact galaxies and N galaxies
                  60          Multiple systems
                  70          Peculiar galaxies
                  90          No galaxy class given

Sequence_Number
The IPC Field Number in which the X-ray flux was measured. If more than one IPC field was measured, a -1 is given here, and the fields used are given in Table 8 of the published paper.

Exposure
The total exposure time, in seconds, for the IPC images, summed over all observed fields.

RA
The Right Ascension of the galaxy in the selected equinox. This is the optically derived position at which the X-ray image was searched. The RA was given in 1950 coordinates to a precision of 0.01 minutes of time in the original table. For Shapley-Ames galaxies (galaxy_sample = 'S-A'), the positions come from the RC2, for UGC galaxies (galaxy_sample = 'UGC'), the positions are as determined either by Dressel & Condon (1976ApJS...31..187D) or from the catalog authors' own measurements (the accuracy of the positions is +/-8 arcseconds), while for ESO galaxies (galaxy_sample = 'ESO'), the positions come from the ESO-LV Catalog (Lauberts & Valentijn, 1989, CDS Cat. <VII/115>).

Dec
The Declination of the galaxy in the selected equinox. This is the optically derived position at which the X-ray image was searched. The Dec was given in 1950 coordinates to a precision of 0.1 arcminutes in the original table. For Shapley-Ames galaxies (galaxy_sample = 'S-A'), the positions come from the RC2, for UGC galaxies (galaxy_sample = 'UGC'), the positions are as determined either by Dressel & Condon (1976ApJS...31..187D) or from the catalog authors' own measurements (the accuracy of the positions is +/-8 arcseconds), while for ESO galaxies (galaxy_sample = 'ESO'), the positions come from the ESO-LV Catalog (Lauberts & Valentijn, 1989, CDS Cat. <VII/115>).

LII
The Galactic Longitude of the galaxy.

BII
The Galactic Latitude of the galaxy.

Count_Rate
The Einstein IPC (X-ray) count rate measured for the galaxy, in ct/s. This count rate has been corrected only for dead-time and background.

Count_Rate_Error
The error in the Einstein IPC (X-ray) count rate, in ct/s.

Conversion_Factor
The multiplicative conversion factor to convert the vignetting-corrected and dead-time-corrected IPC count rate, in ct/s, to an X-Ray flux in the 0.5 to 4.5 keV energy range, in units of 10-11 erg cm-2 s-1, for an assumed HI column density and source energy distribution, as discussed in section 2.2 of the published paper.

Vignet_Correction
The IPC vignetting correction (to be divided into the observed count rate) to the X-Ray count rate. If more than one IPC image was used for the observed count rate, the vignetting correction given here is the exposure-weighted average of the individual vignetting corrections.

Aperture_Code
A numerical code for the largest aperture used to obtain the X-Ray count rate, where 1 means a 200 arcsecond aperture, 2 means a 232 arcsecond aperture, 3 means a 264 arcsecond aperture, and 4 means a 296 arcsecond aperture.

Radial_Velocity
The heliocentric radial velocity of the galaxy, in km/s, from sources as cited in the paper, including the RC2 (CDS Cat. <VII/112>), RC3 (CDS Cat. <VII/155>), and the NASA Extragalactic Database (NED).

Distance
The distance of the galaxy, in Mpc, based on the reference for the distance (ref_distance), and assuming a Hubble Constant H0 of 75 km/s/Mpc.

Ref_Distance
A numerical code for the source of the distance estimate. All independent distance measurements come from Willick et al. (1996ApJ...457..460W and ADC-distributed data base); see references therein for details of individual data sets. The abbreviations correspond to the notation of Willick et al.

     1 = Faber et al. (1989, Cat. <VII/176>)
     2 = Tormen & Burstein reanalysis of Aaronson et al. (1982, Cat. < VII/75>)
          H-0.05 magnitudes (A82);
     3 = Han, Mould et al. Northern survey data (e.g.,
           Han & Mould, 1992ApJ...396..453H; HM);
     4 = Han, Mould et al. Southern survey data (e.g.,
           Han & Mould, 1992ApJ...396..453H; HM);
     5 = Courteau and Faber data (CF; Courteau, 1992, Ph.D. Thesis);
     6 = Mathewson, Ford & Buchhorn (1992ApJS...81..413M; MAT);
     7,8 = Willick (Willick et al., 1996ApJS..109..333W);
     9 = from Faber-Burstein Great Attractor velocity field model for an
          associated cluster or a Local Group galaxy;
    10 = from Faber-Burstein Great Attractor velocity field model for this
          galaxy;
    90 = from Mark II data set (Burstein, 1989, Mark II Catalog of Galaxies
           Peculiar Velocities, email distribution);
    99 = from Willick et al. (1996ApJS..109..333W) but observed 2 or more times.

Abs_Bmag
The absolute blue magnitude of the galaxy, corrected for Galactic extinction from Burstein & Heiles (1984ApJS...54...33B and from the BH reddening maps) and redshift/K-correction via RC2 principles. For spiral and irregular galaxies, this has been also corrected for inclination-dependent internal extinction via the general RC3 relation: {delta}B_T=-1.5log(a/b), where a/b is the observed axial ratio. For UGC and ESO galaxies, this is set to 0.00 if no magnitude is given.

Log_Diameter
The logarithm of the absolute (metric) diameter, log D25, in kpc, based on the 25th magnitude isophote in the B band. This has been corrected for Galactic extinction only, i.e., no inclination correction has been made. For ESO galaxies, this is set to 0.00 if no distance is given.

Log_Lx_Limit
This flag is set to '<' to indicate that the quoted X-Ray luminosity is an upper limit. If blank, this implies that there is a >2.5 sigma X-ray detection of the galaxy.

Log_Lx
The logarithm of the absolute, fully-corrected X-Ray luminosity, in erg s-1 = 10-7 W. This is an upper limit if log_lx_limit - '<'.

Seyfert_Code
A code used to describe the type of Seyfert galaxy, based on Seyfert classifications taken from NED:

                blank = not a Seyfert
                1 = Seyfert 1
                2 = Seyfert 2
                3 = Seyfert ?

Galaxy_Sample
A HEASARC-created parameter describing which galaxy sample the galaxy comes from: a value of 'S-A' means that it is a Shapley-Ames galaxy whose properties are listed in Tables 5 and 12 of the published paper, a value of 'UGC' means that it is a UGC galaxy whose properties are listed in Tables 6 and 13 of the published paper, and a value of 'ESO' means that it is an ESO galaxy whose properties are listed in Tables 7 and 14 of the published paper.

Class
The HEASARC Browse object classification. The HEASARC has not attempted a fine classification based on the morphological T-types, but has here simply used the values of the seyfert_code parameter to indicate the Seyfert galaxies in the table.


Contact Person

Questions regarding the EINOPSLGAL database table can be addressed to the HEASARC Help Desk.
Page Author: Browse Software Development Team
Last Modified: Monday, 16-Sep-2024 17:26:51 EDT