FAIRALL91: southern redshifts catalogue
Table name: fairall
Spectral Band: OPT,RADIO
Kind of Object: Galaxy,BlLac,Radio Sources,Seyfert
- Publications of the Department of Astronomy, University of Cape Town
1991, No. 11 A.P. Fairall and A. Jones
This catalogue provides a "best-estimate" of the heliocentric radial
velocities of some 13000 galaxies south of Declination 0 degrees. It is based
on over 17000 redshift measurements, from over 200 sources, either published or
otherwise made public. Aside from redshift references, each entry includes
flags as to whether the velocity is from optical or radio observations, or both,
as well as an indication of the nature of any optical emission lines. Galaxies
with velocities beyond 75000 km/s are not included. All entries have been made
interactivly, by one person (A.P.F.). The interaction was necessary because
different investigators may use different names, quote slightly different
positions, and obtain slightly different velocities for the same galaxy. Thus
duplicate entries for the same galaxy are avoided (although a few may
inevitably be included).
name Object Name
ra_ori R.A. B1950
dec_ori Declination B1950
lii_ori Galactic Longitude (precision: tenth of degree)
bii_ori Galactic Latitude (precision: tenth of degree)
ref1 Reference (see catalogue Fairall91_ref)
type Kind of object:
S1 Seyfert 1
S2 Seyfert 2
S3 or S? Suspected Seyfert
BL BL Lac object
H2 H II emission, generally implying strong emission
lines of relatively high excitation, including
[O III] 5007 + 4959 emission
EM Generally implies low-excitation
emission, [O II] 3727 and/or H-alpha,
or unspecified emission
band_flag The reference or references only give optical velocities
R - The reference or references only give radio velocities
B - Both optical and radio velocities
ra Right Ascension J 2000
dec Declination J 2000
lii Galactic Longitude (full precision)
_bii Galactic Latitude (full precision)
This catalogue was first published in 1981. The present work is an update
and extension of the 4th version, completed in January 1988. Since that
version, the northern Declination limit has been shifted from -17.5 degrees to
the equator, and radio velocities have been included. The new version,
including updated references, has just over double the number of galaxies in
the previous version. While most of the references are original source papers,
the catalogue was founded on the de Vaucouleurs Second Reference Catalogue
(Ref 001) to take care of references prior to 1975. In similar fashion, the HI
database of Bottinelli et al (Ref 150), published in 1990, has been used to
fill in many of the radio velocities. Literature searches have been made
covering the main journals up to Apr-Jun 1991. Whilst the aim is to obtain all
available redshifts, experience has shown that, inevitably, some references
are overlooked, and no claim to completeness can be made. This is particularly
applicable to the Declination zone 0 to -17.5 degrees, into which the catalogue
has recently been extended. Apologies are made to any author whose work has
been unintentionally omitted. We would obviously welcome any reports regarding
The preparation of a definitive catalogue that includes
all sources, with exhaustive searching and detailed checking, is a major task.
Its coverage must necessarilly lag behind current literature. The present work
does not claim to be a definitive work, but its coverage is up to only 3 or 4
months short of its publication.
Past versions of this catalogue have been well received, and demand has
prompted the preparation of the new version. One of us (A.P.F.) is also involved
in the preparation of the definitive updated version of the "Catalogue of
Radial Velocities of Galaxies" with G.G.C. Palumbo, G. Vettolani and G.
Baiesi-Pillastrini, based in Bologna. That catalogue shows all individual
measurements for galaxies over the whole sky. A significant fraction of the
effort to produce a catalogue of this nature goes to dealing with references
that give only designations (not always obvious ones) of galaxies without
providing their coordinates - or which give only galactocentric, not
heliocentric, velocities. Such references can take a considerable amount of
processing, even before they are entered. Authors and referees should appreciate
the importance of accurate coordinates (even with obvious NGC galaxies) for
identification purposes. The released version of this catalogue is a public
version. The full catalogue does include a few hundred addition redshifts
(obtained at the South African Astronomical Observatory, in collaboration with
L. da Costa and his group) that have not yet been published.
The catalogue is managed in IBM-compatible PCs using dedicated software
developed by one of us (A.J.). It allows almost instant access to galaxies at
any coordinate position, or within a chosen error box. It offers full editing
facilties and can produce ASCII files etc. The procedure for entering a new
velocity determination is initiated by typing in (or interactively feeding
from a file) the 1950 coordinates. The computer then searches within 1m in
R.A. and 2 arcmin in Declination (the generous range in R.A. is to allow for
objects close to the pole), so to determine if an entry for the galaxy already
exists. The option is then given to decide whether to add a new entry or edit
an existing one. One of the features of the software package is the
identification of any form of subset of the data - such as all galaxies within
a specified range of R.A. and Declination, range of galactic longitude and
latitude, specified velocity range or common velocity flag, common reference or
common type. Obviously such subsets are not available in this publication, but
special requests can be considered.
The designations have been entirely picked up from the references quoted.
Thus, if references choose to ignore recognised designations (such as NGC or
ESO) they may also be absent in the catalogue. In general, ESO designations
have been contracted to an "E" prefix. When multiple designations cause space
problems, further contractions, such as NGC to an "N' prefix, are made. Further
information to that given below is included, where appropriate, in the reference
1950 Coordinates and galactic longitude and latitude are given. In earlier
versions of the catalogue, declinations were rounded off to the nearest 15
arcsec - this remains for many entries under references 001 to 078. Some
entries from Ref 131 onwards were entered from files (put in the same format
as the Bologna catalogue); these have declinations rounded off to the nearest
6 arcsec. Where galaxies are reported by different observers, small differences
in coordinates sometimes occur, but usually these are less than 3s in R.A. and
30 arecsec in Declination. In general, many observers make use of the Lauberts
catalogue so positions are coincidental in the stated coordinates.
Heliocentric Vel. (cz)
This column provides the "best estimate" of the Heliocentric velocity. If
only a single reference is available, then the value quoted is straight from
that reference. Although individual errors are not shown, a general error for
the reference concerned may be shown in the reference list. We have tried to
provide estimated EXTERNAL errors for the refences. Where these are not shown,
one can assume the standard deviation of the external error to be in the
region 100-120 km/s. As a general rule, the true external errors are twice that
claimed by the authors! Experience has shown that, in general, about one or
two percent of the redshift velocities from a given source are completely
erroneous (and sometimes the percentage is higher). This is apparently
unavoidable, given the nature of optical galaxy spectra or radio confusion,
and even the most careful investigators are sometimes fooled by spurious
features or detections. Similarly, cross correlations on optical spectra can
sometimes latch on to the wrong values. Since the bulk of this catalogue
concerns single reference redshifts, it is possible that 1 percent or so are
erroneous. When two or more redshift references are shown for a galaxy, the
catalogue velocity is a form of mean value, rounded off to the nearest 10 km/s
(except if the velocities agreed to within 20 km/s, when it is rounded to
1 km/s). In deciding this mean value, extra weighting was given to certain
references known to be more accurate. In general, those optical velocities from
higher dispersion spectra (with external errors better than 50 km/s) had triple
weight. Radio redshifts were given still higher weight, but only when
supported by optical observations. If the reference numbers for an individual
galaxy are not sequential (eg 132 076), then the mean value is weighed towards
the value in the first reference (ie 132). The maximum acceptable differences
between optical velocities is considered here to be 400 km/s, that between radio
velocities is 100 km/s. If only two references are available, and there is no
indication as to which is likely to be correct, then, rather than enter an
uncertain value, a flag "LD" (for Large Difference) is substituted when the
difference is greater than the above. Where there are three or more references,
but one is discrepant (the others are considered valid), the discrepant
reference is separated from the others by a blank space (e.g. 079 082 076).
There are, in the catalogue, a few cases where three references fail to show
any agreement, and one case where four different references all show totally
different redshifts for the same galaxy. A few authors quote only
galactocentric, rather than heliocentric, velocities, ie Vo (= V + 300 sin l
cos b); where possible, we have calculated cz = V, but usually rounded off to
10 km s-1. There are other cases where flags occur in place of a velocity.
- SS - Superposed foreground star with near zero velocity.
- NE - No strong emission lines. The quality of the spectrogram did not permit
redshift determination, but strong emission lines can be excluded.
- TF - Too faint. The galaxy is of low surface brightness and only a tentative
redshift (not given) could be obtained, or no redshift obtained from the
- ESO4 - Reference 048. Observed spectroscopically at the European Southern
Observatory, but no accurate redshift apparently yet available.
- NV - Observed spectroscopically but no velocity yet available. Worth
including because of classification under Type column (e.g. Seyfert).
The source references are given a three-digit numerical code. As
mentioned above, the catalogue was originally founded on data extracted from
the de Vaucouleurs Second Reference Catalogue (Reference 001 - which covers
redshift measurements published 1975 and earlier) with subsequent additions
(References 002 onwards). Thus the listing that follows forms a source of
southern redshifts, except that a number of Seyfert galaxies, having a single
reference for a single galaxy, have been put under umbrella Seyfert lists. The
numerical codes for references simply reflect the order in which the data were
entered into the catalogue. It is roughly chronological (but occasionally a
reference overlooked earlier is added). Gaps in sequential reference numbers
result from some consolidation of references used in earlier editions. or
where references are not yet public. When multiple references are listed, the
order may reflect the weighting given to velocities (see above).
The second last column identifies Seyfert galaxies, and partially
identifies other galaxies with emission lines in their optical spectra (where
this can be easily read from the reference concerned).
Abbreviations are as follows:
S1 Seyfert 1
S2 Seyfert 2
S3 or S? Suspected Seyfert
BL BL Lac object
H2 H II emission, generally implying strong
emission lines of relatively high excitation,
including [O III] 5007 + 4959 emission.
EM Generally implies low-excitation emission, [O II] 3727
and/or H-alpha, or unspecified emission.
These classifications are obviously not uniform between different references,
but nevertheless serve as a useful indication.
The flag is as follows:
- O - The reference or references only give optical velocities
- R - The reference or references only give radio velocities
- B - Both optical and radio velocities
1981 Catalogue "A Simple Source Catalogue of Galaxies south of Declination
-17.5 degrees that have been observed spectroscopically" P.J.K. Dobbie and A.P.
Fairall, Publ. Dept. Astr. Univ. Cape Town, No. 4.
1983 Catalogue "A Catalogue of Galaxies south of Declination -30 degrees
that have been observed spectroscopically" A.P. Fairall, L. Lowe and P.J.K.
Dobbie, Publ. Dept. Astr. Univ. Cape Town, No. 5.
1983 Plots "The Spatial Distribution of Galaxies in the Southern Sky" H.
Winkler, Mon. Not. Astr. Soc. Sthn. Africa, 42, 74. "The Spatial Distribution
of Galaxies in the Southern Sky" A.P. Fairall and H. Winkler in "Clusters and
Groups of Galaxies", p. 23. F. Mardirossian et al. (Eds.) Reidel, 1984.
1984 Plots "A Southern Redshift Survey - Redshift-Space Distributions of
Normal and Active Galaxies South of Declination -30 degrees" A.P. Fairall,
Publ. Dept. Astr. Univ. Cape Town, No. 6.
1985 Catalogue "A Catalogue of Galaxies South of Declination -30 degrees
that have been observed spectroscopically (1985 Version)" A.P. Fairall, Publ.
Dept. Astr. Univ. Cape Town, No. 7. Machine-Readable Version by Anne C. Raugh
(March 1987) distributed by the Astronomical Data Center, NASA Goddard Space
1988 Catalogue and Plots "Southern Redshifts - Catalogue and plots" A.P.
Fairall and A. Jones, Publ. Dept. Astr. Univ. Cape Town, No. 10.
Machine-Readable Version by Anne C. Raugh (January 1989) distributed by the
Astronomical Data Center, NASA Goddard Space Flight Center.
1990 Plots "Large-Scale Structure in the Universe: Plots from the Updated
Catalogue of Radial Velocities of Galaxies and the Southern Redshift Catalogue"
A.P. Fairall, G.G.C. Palumbo, G. Vettolani, G. Kauffmann, A. Jones and G.
Baiesi-Pillastrini, Mon. Not. R. astr. Soc., 247, 21P.
The three errors mentioned as "Corrections to October 1991 Version as
noted November 1, 1991" were reported, namely:
- IRAS 09 41 59 (RA) RA corrected to 09 14 59
- NGC 7314 22 30 00 has been deleted
- NGC7314/E533-G53 velocity and references corrected.