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A CATALOGUE OF
SPECTROSCOPICALLY IDENTIFIED
WHITE DWARFS
BY
GEORGE P. McCOOK
EDWARD M. SION
JAN 1988
I. INTRODUCTION
The first edition of this catalogue was published
privately in May 1977(McCook and Sion 1977) as Villanova
University Observatory Contributions No.2 and contained less
than 500 degenerate stars.The preface to that edition
provided a succinct rationale of our motivation for
preparing the catalog and is presented here verbatim:
"The number of newly discovered white dwarfs has
increased substantially since the the appearance of the
first comprehensive list by Eggen and Greenstein in 1965.
The newly observed objects when added to the earlier lists
comprise a sample approaching six hundred stars. New
spectroscopic, spectrophotometric and photometric observa-
tions are being obtained by several active groups throughout
the world. The volume of data is enormous and much of it is
dispersed throughout the literature. Some confusion exists
with nomenclature especially regarding multiple names. The
volume of data and the nature of its accessibility in the
literature strongly suggested the need for a general
comprehensive white dwarf catalogue. While there is clearly
no substitute for using the primary reference literature, it
may prove useful in certain applications for both observers
and theoreticians to have the data collected into one
catalogue. We apologize in advance for the inevitable errors
in a catalogue of this size and welcome corrections and
additions being brought to our attention for inclusion in
possible future editions".
Since the appearance of the First Edition of the
Villanova Catalogue of Spectroscopically Identified White
Dwarfs ,the number of newly identified spectroscopic
degenerates has more than tripled due in a large part to the
identification of several hundred new spectroscopic
degenerates at the 5.1m Hale reflector by Jesse Greenstein
and through the Palomar-Green North Galactic Pole survey of
hot white dwarfs by R. Green, M. Schmidt, and J. Liebert.
In addition, multi-channel spectrophotometry by Greenstein
and Green is now available for over 500 white dwarfs while
over 300 stars have Stromgren photometry due mostly to
J.Graham ,G. Wegner, O. Eggen, M. Bessel, and D.T.
Wickramasinghe. We decided in 1979 to postpone publication
of the second edition until the large sample of hot white
dwarfs discovered in the Palomar Green Survey became
available for inclusion. In doing so ,the second
edition(McCook and Sion 1984) presented a sample of nearly
1500 degenerate stars and a very much more complete
compilation of color and parallax data for the proper motion
selected sample.
It was felt that the publication of the Villanova
Catalogue of Spectroscopically Identified White Dwarfs,
Third Edition, in the Astrophysical Journal Supplement
would greatly increase its user accessibility and offer the
opportunity to incorporate revisions, corrections and some
additions to the second edition.
The finalized Palomar-Green sample of degenerate stars
(Green, Schmidt and Liebert, 1986) contained a number of
revised object and spectral classifications resulting from
extensive follow-up spectroscopy of the many objects having
only single discovery spectra at lower resolution. As a
result 30 Palomar-Green objects, misclassified as white
dwarfs have been deleted from our catalogue, 16
Palomar-Green objects reclassified as degenerate stars have
been added and 276 Palomar-Green stars were given revised
spectral classifications.
We have also added a large number of newly identified
degenerate stars from the following sources: The Case Low
Dispersion Northern Sky Survey (Sion, Wagner and
Co-workers), the Kiso Ultraviolet Excess Survey (Wegner and
Co-workers), the Kitt Peak Downes Survey (Downes and
Co-workers), 5.1m Palomar CCD Spectroscopy by Greenstein,
and Faint Spectroscopy of Luyten Palomar Proper Motion Stars
by Hintzen. In addition, a number of new parallaxes and
photometric colors have been added, the descriptions of the
names entry have been expanded and the notes section has
been significantly enlarged.
II. SELECTION OF THE DATA, ENTRY CHANGES SINCE THE SECOND EDITION
As in the First edition, we have attempted to include
only white dwarfs with published spectroscopic
identification. In a very few cases, colors and motions
strongly indicate a white dwarf, but no spectral class has
been as yet assigned. We have included white dwarfs that
are components of essentially non-interacting binaries (eg.
Roche lobe detached, short and long period systems) whose
detected photospheric spectra are classifiable. A few
examples illustrate the morphological range of such binary
systems: HZ9, Sirius B, HZ43, the DA component of the mild
Barium star Xi Ceti. We have attempted to include all data
published or released to us in preprint form prior to
January 1987.
Based upon input we have received from colleagues,
content changes have been introduced in the second edition
which it is hoped will help to maximize the scientific
usefulness of the second edition. A new white dwarf
spectral classification system proposed by Sion, Greenstein,
Landstreet, Liebert, Shipman, and Wegner (1983) has been
implemented and is briefly described in the spectral class
entry section below. An absolute visual magnitude has been
computed for each star with measured colors or trigonometric
parallax and the computational procedure is described in the
entry section below. In addition, we have eliminated the
equivalent width entries from the second edition and we have
retained the observed radial velocity entry but eliminated
the radial velocity corrected for solar motion and mean
gravitational redshift. A seven digit WD number has been
adopted and the notes section for white dwarfs of greatest
astrophysical importance has been expanded. Names cross
referenced with WD numbers have been expanded to include
every white dwarf name used in the catalogue. The cross
references are listed in appendix A.
III. THE ENTRIES IN TABLE 2
All entries in table 2 except coordinates, names and
absolute magnitudes are followed by a reference number in
brackets e.g.(41). The reference list can then be used to
identify the source of the catalogue entries.
Column
Heading
WD The first entry contains a 'WD number', a catalogue
number containing the first four digits of right ascension
followed by the sign and the first two digits of declination
and a third digit in which minutes of declination have been
expressed as a fraction of a degree. Stars with identical
catalogue numbers, whether binary or not, have been
distinguished by using the designation .1 and .2 after their
respective catalogue number. The same distinction is used
for wide binary pairs. The choice of the 'WD number' format
was made with the idea of continuing expansion of the
catalogue as data accumulates.
R.A. DEC The second entry contains the full right ascension and
declination (1950.0) adopted according to the following
order of priority: Lowell Observatory coordinates, United
States Naval Observatory coordinates, Luyten Proper Motion
Survey coordinates. For Bruce Proper Motion Survey stars,
the coordinates may refer to epoch 1900.0 if no other proper
motion name is listed.
SP. CL. The third entry lists the spectral type according to the
new system described by E.M. Sion, J.L Greenstein, J.D.
Landstreet,J. Liebert, H.L. Shipman, and G.A. Wegner (1983)
, where a complete discussion may be found. The system uses
(1) an upper case D for degenerate; (2) an upper case letter
for primary spectroscopic type in the optical spectrum; (3)
an upper case letter for weaker or secondary spectroscopic
features, if present, in any part of the electromagnetic
spectrum and (4) a temperature index from 0 to 9 defined by
10 X i (i = 5040/T). Additional symbols to follow the
second upper case letter are upper case P to indicate
polarized magnetic stars, H for magnetic stars showing no
detectable polarization, X for peculiar or unclassifiable
spectra, and an optional V to denote the ZZ Ceti stars or
any other variable degenerate star.
Temperature-color index correlations using model
atmospheres for DA and non-DA stars are available for multi-
channel spectrophotometric colors (g-r); Stromgren colors
(u-b, b-y); and broad band UBV colors (B-V, U-B).
Temperatures derived from different model atmosphere grids
are generally very consistent.
We determine the temperature index by using the color
transformations based upon tables 1 and 2 and equations (9)
and (10) of Shipman (1979). The transformation relations
for non-DA stars are
(B-V) = 0.334 + 0.836 (g-r)
and
(b-y) = 0.286 + 0.553 (g-r).
For DA stars, the color transformations are:
(B-V) = 0.3336 + 0.5906 (g-r)
and
(b-y) = 0.2197 + 0.4485 (g-r).
TABLE 1
-----------------------------------------------------------------
DEFINITION OF PRIMARY SPECTRAL SYMBOLS
Spectral Type Characteristics
DA Only Balmer lines: no HeI or metals
present.
DB HeI lines: no H or metals present.
DC Continuous spectrum, no lines deeper then
5% in any part of the electromagnetic
spectrum.
DO HeII strong: HeI or H present.
DZ Metal lines only: no H or He lines.
DQ Carbon features, either atomic or
molecular in any part of the electro-
magnetic spectrum.
* An asterisk indicates additional informa-
tion in the Notes section, appendix A.
b The letter "b" Indicates a binary member.
-----------------------------------------------------------------
The definition of primary spectral symbols is given in
table 1 according to the Sion et al (1983)
classification.The primary symbols may be combined to
designate atmospheres having hybrid compositions.For example
a DB4 star showing CaII would be DBZ4,a DZ8 star with
detectable H would be DZA8,a DO1 star with CIV(1550) would
be DOZ1,et cetera.If more than one spectral class assignment
has been made and cited and they are in agreement, the
spectral type has been converted to the new system and is
followed by the original reference(s). If more than one
spectral class has been cited and they are in disagreement,
a spectral type converted to the new system is given based
upon our assessment of the spectral resolution and
instrumental technology involved, but the old spectral types
are retained followed by their references. In many cases
the primary classification reference has not been listed but
may be easily found in the secondary reference which is
given.
NAMES The fourth entry contains most of the names that exist
for each star. The names are listed below with most of
their references and an extensive cross reference, to the
names used in Table 2, can be found in Appendix B.
BPM Bruce Proper Motion Survey
see reference list under Luyten
C Case
Stephenson, C.B. 1960,PASP, 72 ,387;1962,PASP, 74 ,610.
CI20 Cincinnati
Porter, J.G., Yowell,E.J., and Smith,E.S. 1930,Publ.
Cincinnati obs.,No.20.
CSO Case Low Dispersion Survey
CBS Pesch, P., and Sanduleak, N. 1983,Ap.J.Suppl., 51 ,171
Sanduleak, N., and Pesch, P.1984,Ap.J. Suppl., 55 ,517.
Pesch, P., and Sanduleak, N.1985,Ap.J.Suppl., 60 ,543.
EG Eggen-Greenstein
See reference list under Eggen and Greenstein.
F Feige
Feige, J. 1958,Ap.J., 128 ,267.
G,GD,GH Lowell Names
see reference list under Giclas
GL Gliese
Gliese, W. Von. 1957,Katalog der Sterne Naher
als 20 parsek fur 1950.0, Heidelberg.
GR Greenstein
See reference list under Greenstein.
GW Greenwich
Astrographic Catalogue 1900.0 Greenwich Section,Vol.3
+64 to +90, F.W.Dyson,1914.
HE Hertzprung
Hertzsprung,E. 1918,A.N., 207 ,171.
HL Tonantzintla
Haro,G. and Luyten,W.J.1960,Bol. Obs.
Tonantzintla y Tacubaya,No.29,16.
HZ Humason-Zwicky
Humason, M., and Zwicky, F. 1947,Ap.J., 105 ,85.
K1 Kohoutek (K1-16)
Perek, L., and Kohoutek, L.
Catalogue of Galactic Planetary Nebulae 1967,Academia
publ. house of the Czechoslovak Academy of Sciences,
p.276,(Prague).
Karpov (K1-12)
Karpov, B.G. 1937,Pub.A.S.P., 49 ,146.
KUV Kiso
Kondo, M., Watanabe, E., Yutani, M., and
Noguchi, T. 1982,Publ.Astron.Soc.Japan, 34 ,541.
Noguchi, T., Maehara, H., and Kondo, M. 1980,Ann.Tokyo
Astr.Obs.,Ser.2, 18 ,55.
Kondo, M., Noguchi, T., and Maehara, H., 1984,Ann.Tokyo
Astr.Obs.,Ser.2, 20 ,130.
KPD Kitt Peak Downes
Downes, R. 1986,Ap.J.Suppl. 61 ,569.
L,LB,LP Luyten Names
LDS,LHS,LTT see reference list under Luyten
MK Markarian
Markarian,B.E.,and Lipovetski,V.A. 1971,
Astrofizika, 7 ,511.
PB Palomar-Berger
Berger, J., and Fringant, A. M. 1977,Astr.Ap.Suppl.,
28 ,123 and subsequent papers.
PG Palomar-Green
Green, R.F., Schmidt, M., and Liebert, J.W.
1986,Ap.J.Supp., 61 ,305.
PHL Tonantzintla
Haro,G. and Luyten,W.J.1962,Bol. Obs.
Tonantzintla y Tacubaya,3,No.22.
R Ross
Ross,F.E. 1925-1939,A.J., 36-48 .
RB RWT Rubin
Rubin, V.C., Westphal, D., and Tuve, M.
1974,A.J., 79 ,1406.
SA Basle Halo Program
Steppe,H.1978,Astr.Ap.Suppl., 31 ,209.
SB Slettebak and Brundage
Slettebak,A. and Brundage,R.K.1971,A.J., 76 ,338.
TC Tonantzintla
TON Iriarte, B., and Chavira, E. 1957,Bol.Obs.
TPS Tonantzintla y Tacubaya,16,3.
TS Chavira, E. 1958,Bol. Obs. Tonantzintla y
Tacubaya,No.17.
Chavira, E. 1959,Bol. Obs. Tonantzintla y
Tacubaya,18,3.
Philip,A.G.D. and Sanduleak,N.1968,Bol. Obs.
Tonantzintla y Tacubaya,4,No.30.
US Usher
Usher, P. D. 1981,Ap.J.Suppl., 46 ,117 and
subsequent papers.
VB Van Biesbroeck
Van Biesbroeck, G. 1961,A.J., 66 ,528.
V Ma Van Maanen
Van Maanen, A. 1938,Ap.J., 88 ,27.
VR Van Rhijn-Raimond
Van Rhijn, P.J. and Raimond, J.J. 1934,M.N.R.A.S., 94 ,508.
W Wolf
Wolf, M. 1919,Sternwarte zu Heidelberg,1,no.10,
A.N., 209-236 ,1919-1929.
Other Other Names--Refer to Fernandez,A.,Lortet,M.-C.,Spite,F.
1983,Astron.Astrophys.Suppl., 52 ,NO.4.
WIDE BAND Entry five contains published values of wide band UBV
V B-V U-B photometry. The V magnitude is listed followed by B-V,
U-B and the reference number. If the star has not been
observed on the UBV system, a photographic magnitude and
color class (CC) is given from either the Lowell or Luyten
Proper Motion Surveys. Photographic magnitudes are indicated
by a PG following the magnitude in the V column.
MC MC Entry six contains multi-channel spectrophotometric
V g-r observations. The multi-channel V magnitude is listed
followed by the multi-channel color and the reference.
STROMGREN The seventh entry lists the Stromgren, narrow band,
y b-y u-b photometry, y, b-y, u-b, and the reference.
Mv The eighth entry lists the absolute visual magnitude
computed from either trigonometric parallax or measured
colors according to the following priority: (1)
trigonometric parallax > 0".1 (2) multi-channel
spectrophotometric colors (3) Stromgren narrow band colors
and (4) UBV photometry. Exceptions to this priority system
are denoted with numerical codes (0),(5), and (6) and are
described below. If measured colors do not exist, an
absolute magnitude was not given. For all spectral types
with (g-r) color index the following calibration formula due
to Greenstein (1984) was employed:
Mv = 13.033 + 3.114 (g-r) -0.799 (g-r) 2
For all spectral types with (b-y) color index, the
following calibration due to Green (1977) was adopted:
Mv = 7.56 (b-y) + 11.50.
The broad band calibrations are those of Sion and
Liebert (1977). For DA white dwarfs with B-V < 0.4:
Mv = 11.246 (B-V+1) 0.60 -0.045.
For non-DA stars with B-V < 0.4:
Mv = 11.916 (B-V+1) 0.44 -0.011.
If B-V > 0.4 we used the following color-magnitude
calibration due to Dahn et. al. (1982):
Mv = (11.43q0.16)+(7.25q0.75)(B-V)-(3.42q0.68)(B-V) 2
In a few cases where 3 or more measured parallaxes from
different sources are in agreement, exceptions were made to
the priority system above. Likewise, for degenerate stars
whose spectra exhibit abnormally strong or peculiar
blanketing (e.g. G47-18, GD 229, LP701-29) and for very
cool white dwarfs (e.g. LP131-66) the above priority system
was not followed.Since for cool white dwarfs ,the blue
colors(e.g.B-V,b-y,g-r) yield less accurate photometric
parallaxes than the red colors(e.g.V-I,R-I),we have adopted
absolute magnitudes from the recent tabulation of cool white
dwarfs by Liebert,Dahn and Monet(1987) if our values
differed by more than 0.3 magnitudes from theirs. These
values are denoted by numerical code (6). An extensive
tabulation of red colors of white dwarfs can be found in a
review by Eggen(1985 and references therein) while V-I color
indices are available from the USNO faint star parallax
lists cited in this catalogue. Likewise for the very hot DA
stars where the blue-sensitive color-magnitude calibrations
are insensitive to temperature,we have used the values of M
derived from actual effective temperature determinations as
given for example,by Fleming et al.(1986) and Holberg et
al.(1986).Here again however their values were adopted only
if a discrepancy greater than 0.3 mag. existed. These
values are denoted by numerical code (0). For the hottest
helium-rich degenerates the photometric parallaxes are
grossly inaccurate.For the DO and DOZ white dwarfs ,we have
replaced the M value with the directly derivable effective
temperature in units of 10 K. Most of the adopted values
were from Wesemael et al.(1985) and are indicated by
numerical code (5).
A discussion of the dispersions and analysis of the
above calibrations is given in Sion (1979) and Sion (1984).
The value of absolute visual magnitude is followed by a
number 1,2,3 or 4 to indicate the method of determination;
(1) parallax; (2) multi-channel color; (3) Stromgren color
and; (4) UBV color, or the value is followed by (0), (5) or
(6) as described earlier. Stars with hybrid classifications
were generally not assigned a photometric parallax.
MU THETA The ninth entry contains the published values of proper
motion and position angle followed by the reference. The
units are seconds of arc per annum for proper motion, and
degrees for the position angle.
VR0 The tenth entry lists the observed radial velocity
uncorrected for solar motion and gravitational redshift and
followed by the reference.
PI ME The final catalogue entry lists the published values of
the trigonometric parallax in second of arc. In most cases
the parallax is followed by the reported mean error in units
of 0.001 seconds of arc.
We are grateful to the many colleagues,too numerous to
mention, who communicated data to us in advance of
publication, and who sent to us, corrections and suggestions
concerning the format and content of this edition. It is a
pleasure to express our deepest gratitude to Drs. Jesse
Greenstein and James Liebert for their valuable and detailed
comments on this edition and to Dr. Hugh M. Van Horn at
whose urging we decided to seek publication in a major
journal instead of continuing to issue the catalogue
privately. We thank William Harris,Kevin Hart,Brian
McNamara, Robert Donahue, Scott Wacker, Raj Goyal, Matthew
Lallo, and Joseph McMullin for their careful assistance with
proofreading and data compilation. We gratefully
acknowledge the support of the National Science Foundation
through Grants AST78-13396-A01-A02 and AST85-17125 to
Villanova University.
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© UDS/CNRS