VII/142A Southern Redshifts Catalogue (Fairall+, 1991)
Southern Redshifts Catalogue and Plots
Fairall A.P., Jones A.
<Publ. Dept. Astron., U. Cape Town No. 11 (1991)>
=1991srcp.book.....F 1991srcp.book.....F
ADC_Keywords: Galaxies, optical; Redshifts
Abstract:
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
interactively, 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).
Introduction:
Previous Versions of this Work:
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 Flight Center.
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.
Coverage and Completeness:
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. Whilst 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. The authors would obviously welcome
any reports regarding reference coverage. The preparation of a
definitive catalogue that includes all sources, with exhaustive
searching and detailed checking, is a major task. Its coverage must
necessarily 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 the authors (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.
Computer Management of the Catalogue:
The catalogue is managed in IBM-compatible PCs using dedicated
software developed by one of the authors. It allows almost instant
access to galaxies at any coordinate position, or within a chosen
error box. It offers full editing facilities 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.
Hardcopy and Computer-readable Versions of this Catalogue:
This catalogue is being distributed in two forms. One is a
conventional printed version, the other is a weight-reduced version
with the catalogue and reference lists compressed onto a computer
diskette. The computer-readable version is distributed by the
Strasbourg and Goddard data centres.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
catalog.dat 96 12843 The catalogue
refs.dat 80 604 The references (371 non-blank lines)
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Byte-by-byte Description of file: catalog.dat
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Bytes Format Units Label Explanations
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1- 20 A20 --- ID *Designation
22- 23 I2 h RAh *Right ascension hours, 1950.0
25- 26 I2 min RAm *Right ascension minutes, 1950.0
28- 29 I2 s RAs *Right ascension seconds, 1950.0
31 A1 --- DE- Declination sign
32- 33 I2 deg DEd *Declination degrees, 1950.0
35- 36 I2 arcmin DEm *Declination minutes, 1950.0
38- 39 I2 arcsec DEs *Declination seconds, 1950.0
41- 45 F5.1 deg GLON Galactic longitude
47- 51 F5.1 deg GLAT Galactic latitude
53- 57 I5 km/s cz *?Velocity
59- 85 A27 --- r_cz *Comma-separated list of references
87- 88 A2 --- type *Classification of Galaxy
91 A1 --- f_cz *Flag for radio/optical cz origin
93- 96 A4 --- n_cz *Velocity flags
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Note on ID:
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 lists.
Note on RAh, RAm, RAs, DE-, DEd, DEm, DEs:
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.
Note on 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. The authors 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
Note on n_cz:
There are other cases where flags occur in place of a velocity. These are:
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 spectrogram.
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).
Note on r_cz:
The source references are given three-digit numerical codes (see
refs.dat). 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).
Note on type:
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.
Note on f_cz:
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
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Byte-by-byte Description of file: refs.dat
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Bytes Format Units Label Explanations
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2- 4 I3 --- Ref Reference number
6- 80 A75 --- Text Text of reference
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Acknowledgements:
The authors thank. Penny Dobbie is thanked for help with layout and
printing of the catalogue. They also thank various colleagues who have
reported corrections to the previous version, particularly H. Winkler,
H. Andernach, V. Liporetsky and G. Paturel. The Foundation for
Research Development and University of Cape Town have provided
research funding that contributed to the production of this work.
History:
The original document was prepared by the authors in October 1991. The
contact for the first author is:
Anthony P. Fairall, Department of Astronomy, University of Cape Town,
Rondebosch. 7700 SOUTH AFRICA
Telephone: (27)(21)650-2392 Fax: (27)(21)650-3726 E-mail:
The document was prepared for the ADC by Anne C. Raugh and converted
to the current standard form by the undersigned. The format tables
were added. Various corrections were made to catalog.dat and the blank
lines were removed from the reference tables.
* 11-Jan-2003: two corrections forwarded by H. Adernach to CDS:
- duplicated record at B1950 17:20:48-00:14:16 removed
- missing - sign for Declination of MCG+0-24-9 added.
* 19-Feb-2003
References rearranged, and ref.029 added thanks to Tony Fairall.
(End) Nancy G. Roman [ADC/SSDOO] 26-Jul-1995