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ESOLV: ESO Catalogue of Galaxies

Contents

Table name: 	ESOLV
Records:  	15467
Version:	Lauberts-Valentijn 1989
Spectral Band: 	OPT,Bphoto,Rphoto
Kind of Object: Galaxy
Mode: 		Morphology,Survey
PreView:	Yes
Coordinates: 	B1950

Reference

Description

A visual scan of the ESO Quick Blue Schmidt survey plates resulted in a catalogue containing information on 14,155 galaxies defined with (del) < -17:5O and a visual diameter larger than 1 arcmin. This catalogue was published in 1982 by Lauberts and provides information on the positions, morphological types, diameters, axial ratios and position angles. Most of the galaxies were catalogued for the first time. We hereafter refer to this catalogue as 'ESO-Uppsala catalogue ' or 'the ESO-Uppsala catalogue catalogue'.

Since all the information present in ESO-Uppsala catalogue was acquired by visual inspection of the plates, it was decided to undertake a follow up study, in which computerized processing takes the central place. Hereafter we will refer to the present study and its results as ESO-LV. The visually obtained results of ESO-Uppsala catalogue are quite complementary to the automatic processed data of ESO-LV. It should be noted however, that the original ESO-Uppsala catalogue catalogue was used as a reference data base for the processing of ESO-LV and that without this reference this project would not have been possible.

The prime objective of ESO-LV was to obtain accurate magnitudes for the ESO-Uppsala catalogue galaxies. To this end target galaxies have been scanned on both the 407 original ESO Quick Blue survey plates and on the 407 original ESO Red survey plates. It was soon realized that the scanned images of the galaxies could also be used to obtain other photometric and structural parameters.

The scan aperture was always 20x20 microns, using a 10x magnification objective. A smaller aperture, of say 10 microns, was rejected from the beginning because of uncotrollable focus variations. The step size, 20 microns, had to be kept relatively large in order to save time. With a plate scale of 67.5"/mm, the pixel size of 1.35" was significantly smaller than the average seeing of 2".

A full description of the automated parameter extraction procedures is given in Section 5 of [1]. The printed version of the newly determined parameter values, which can be found at the end of this book, contains 37 different entries, while the digitized versions contain up to 180 entries, including radial surface brightness profiles. This data base (180 entries for 16000 galaxies) can be considered the principal result of the project. The data will be made available to the astronomical community in several forms: on the ESO data base computer (IDM), as a MIDAS table on the ESO VAX computers and on magnetic tape. Beside that, the images used in this survey and calibrated to surface brightness are resident on an ESO optical disk drive (see [1] Section 10).

All plates have been calibrated by using 'standard' galaxies, for which aperture photometry has been accumulated both from the literature and from our own photo-electric observations. The photo-electric (p.e.) observations and the conversion to a 'standard system' are described in [1] Section 3. A previous version of the p.e. data base has been published in ESO Scientific report No 3. The procedures followed for scanning and calibrating the plates are described in [1] Section 4. The calibration coefficients of the 814 plates form an interesting data base on the properties of sensitized (Red) and unsensitized (Blue) plates. At the end of Section 4 we present some statistics on these quantities, also including the sky brightness values.

The accuracy of the derived photometry is discussed in [1] Section 7. Both internal consistency checks and comparisons with other photometric observations are presented. The nominal accuracy of total magnitudes, Btot, is expected to be better than 0.09, most likely around 0.06, for galaxies brighter than Btot= 15, while surface brightness (mu) profiles are found to have residuals from photoelectric photometry less than 0.15 for 20 < (mu)B < 24.

The photometric and structural parameters have been used to determine morphological types for ~ 3500 galaxies that could not be classified in ESO-Uppsala catalogue, mostly because they were too faint. The availability of colours and profile gradient parameters allowed us to evaluate in an automated mode the expected morphological type. We have also made extensive use of the recently published classifications by Corwin et.al.(1985). The morphological re-classification is described in [1] Section 6.

A strong aspect of the ESO-LV data base is that data have been acquired in a homogeneous fashion for all sorts of galaxies in various environments. Thus it appears that scientific studies of galaxy properties as function of environment might be fruitful with this data base. In order to facilitate such studies, we have attempted to construct a local projected galaxy density parameter, despite the lack of redshifts for the majority of the catalogue galaxies. Data on Southern Clusters from Abell et.al.(1989) have been incorporated in the galaxy density parameters. A full description is given in [1] Section 8.

In [1] Section 2 we give an account on the construction of the sample, while in Section 9 an analysis is presented of the selection effects inherent in a diameter selected sample, in addition to a discussion on the completeness of the sample with respect to its selection criteria. A Vmax complete sample is drawn from the total sample.

Fields

Name	Col	Fmt	Meaning

a_e	125	F8.1	ABe aperture of circle enclosing half total B light
ab_ado	116	F8.2	a_b0 a/b adopted for computing parameters in ellipses
ab_oct	113	F8.2	a_b0     a/b from ellipse fit to B octants
b_b25	19	F8.2	B25      B mag within ellipse at B sb=25 mag/sq arcs
b_b26	17	F8.2	B26      B mag within ellipse at B sb=26 mag/sq arcs
b_sky	107	F8.2	(mu )BskyBlue sky background, mag/sq arcsec
b_tot	15	F8.2	BT       B mag, total
br_10	100	F8.2	(B - R)10"B-R integrated in central 10" diameter circle
br_d	171	F8.2	4(B - R) difference of B-R of regs (outside - inside) 
			B eff radius
br_e	99	F8.2	(B - R)e B-R integrated in ellipse enclosing half total
			B light
br_t	101	F8.2	(B - R)T B-R total colour
bs_0	104	F8.2	(mu )B0  average B surface brightness, within 10" circ
			aperture
bs_e	143	F8.2	(mu )Be  B sb at B half total light (only if d_e > 10") 
bt_flg	11+112	A1	BflagNresB number of radii susp saturated:

			-   replaced with photoelectric data
			0   deblended
			1,2 Number of radii suspected saturated

c	182	I4	sample   Completeness: 0=not, 1=E/U diam   1', 2=Vmax 
			complete
cz	13	F6.0	cz       radial velocity, helio-centric, km/sec
d25	109	F8.1	DB25     major diameter (arcsec) of ellipse at B sb 25
			mag/sq arcs
d26	110	F8.1	DB26     major diameter (arcsec) of ellipse at B sb 26
			mag/sq arcs
d27	111	F8.1	DB27     major diameter (arcsec) of ellipse at B sb 27
			mag/sq arcs
d70	119	F8.1	DB70     major diameter (arcsec) of ellipse at B 70% 
			total B light
d80	120	F8.1	DB80     major diameter (arcsec) of ellipse at B 80% 
			total B light
d90	121	F8.1	DB90     major diameter (arcsec) of ellipse at B 90% 
			total_B light
d_e	122	F8.1	DBe      major diameter (arcsec) at B half total light
dec	10	F8.3	DEC      Dec (1950), degrees
descr	190	A52	descriptionOriginal classification and comments 
			(old +new)
dnb	152	F8.0	Dnb      distance to nearest neighbour, arcsec
dsnb	155	F8.0	Dsnb     distance to second nearest neighbour, arcsec
e_cz	14	F6.0	czerr    error in radial velocity
eso	1	I8	ESOindentESO field number / galaxy number 
			PIDM.FMT 890502
ic	3	I6	IC       IC number (if negative then additional NGC no)
mt	7	F6.1	Type    morphological type T [-6,+10], revised 
			according to S. A value of -9.0 means unknown
nearn	151	I8	IDnb     identifier of nearest neighbour
ng_sp	131	F8.3	Nsp     No of galaxies/sq degree, Spir, 0   
			Type < 8.5.  A value of -9.000 means unknown
ng_t	127	F8.3	Ntot    Total no of galaxies/sq degree in 1 degree 
			radius circle. A value of -9.000 means unknown
ngc	2	I6	NGC      NGC number (if negative then additional IC no)
noct_b	150	F8.3	NBoct    exponent of fit generalized law to B octants
noct_r	162	F8.3	NRoct    exponent of fit generalized law to R octants
pa_ado	118	F8.1	p:a:0    position angle adopted for parameters in 	
			ellipses
pa_oct	114	F8.1	p:a:1    position angle from ellipse fit to B octants
r_a	9	F8.3	RA       R.A. (1950), degrees
r_b25	20	F8.2	R25      R mag within ellipse at B sb=25 mag/sq arcs
r_b26	18	F8.2	R26      R mag within ellipse at B sb=26 mag/sq arcs
r_sky	108	F8.2	(mu )RskyRed sky background, mag/sq arcsec
r_tot	16	F8.2	RT       R mag, total, with same limiting boundary as 
			B_TOT
rs_0	146	F8.2	(mu )R0  average R surface brightness, within 10" circ 
			aperture
rs_e	144	F8.2	(mu )Re  R sb at B half total light (only if d_e > 10 
			arcsec)
rt_flg		A1	R number of radii susp saturated (-: repl with pe, 0: 
			deblended)
s	8	I4	Tflag    Source for T: 1=vis revised, 2=Corwin, 3=T_OLD,
			4=T_PAR
secnb	154	I8	IDsnb    identifier of second nearest neighbour       

The Catalog Table

The ESO-LV catalog is also available as a compressed binary FITS table (Size: 6.1 MB).

Contact: ESO Operational Helpdesk

Last modified: Tue May 27 10:13:32 MET DST