J/MNRAS/260/77 ROSAT Wide Field Camera EUV Bright Sources (Pounds+ 1993)
The ROSAT Wide Field Camera all-sky survey of extreme-ultraviolet sources -
I. The Bright Source Catalogue
Pounds K.A., et al.
<Mon. Not. R. Astron. Soc. 260, 77 (1993)>
=1993MNRAS.260...77P 1993MNRAS.260...77P
ADC_Keywords: X-ray sources
Description (Summary):
Table 1 gives the coordinates (equinox J2000.0) of 384 bright EUV
sources detected in the WFC survey. These should be referred to,
according to the IAU convention, by the suitably truncated RA and Dec.
Thus, the first source in the Table is RE J0003+433, a ROSAT EUV
source at 00h 03m and +43deg 35'. Count rates and 1sigma errors are
given for each of the survey filters, in counts per kilosecond. Upper
limits are indicated by "-" in the error column and are 3sigma above
the local background.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1 129 498 The Bright Source Catalogue
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Byte-per-byte Description of file: table1
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Bytes Format Units Label Explanations
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2- 3 I2 h RAh Right Ascension J2000 (hours)
5- 6 I2 min RAm Right Ascension J2000 (minutes)
8- 11 F4.1 s RAs Right Ascension J2000 (seconds)
13 A1 --- DE- Declination J2000 (sign)
14- 15 I2 deg DEd Declination J2000 (degrees)
17- 18 I2 arcmin DEm Declination J2000 (minutes)
20- 21 I2 arcsec DEs Declination J2000 (seconds)
23- 27 I5 ct/ks S1a ?Count rates in filter S1 (90-206eV)
29- 31 I3 ct/ks e_S1a ?mean error on S1a
33- 37 I5 ct/ks S2a ?Count rates in filter S2 (62-110eV)
39- 41 I3 ct/ks e_S2a ?mean error on S2a
43- 57 A15 --- Name1 Possible counterpart (1)
59- 70 A12 --- Name2 Possible counterpart (1)
72- 87 A16 --- Type Counterpart type
90- 93 F4.1 mag Mag ?Counterpart magnitude
94 A1 --- n_Mag Note on the Counterpart magnitude
96-115 A20 --- Comments See Note (2)
117-119 I3 arcsec R90 ?90%-confidence position error circle radius
121-123 I3 arcsec DR ?Counterpart offset from EUV source position
125-127 A3 --- Cat Catalogue from which the counterpart position
was taken
129 A1 --- Rem 'R' for Notes (see below)
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Note (1):
Information on possible counterparts within the 99.9% WFC position
error circle is given. The first counterpart listed is thought to be
the most likely identification from the information available in
existing catalogues and optical follow up work on some sources (Mason
et al., 1992). Extensive use was made of the CDS SIMBAD database,
particularly for obtaining information on multiple names for objects.
Two names are usually given for the first counterpart; normally a
common or variable star name, followed by an HD or WD (McCook and
Sion, 1987) number, where available. One name is generally given for
other objects within the 99.9% error circle. Information on many of
the object names used here can be found in Fernandez et al.
(1983). Object types for the counterparts are given; spectral type
classifications for the same object, but from different catalogues,
are all listed, separated by slashes. For more detailed and accurate
spectral type classifications for active binaries, see Strassmeier et
al. (1988). The magnitudes of the counterparts are given (usually in
the V-band unless B magnitudes are indicated by a "B"). They are meant
only as a rough guide, since they are drawn from a variety of
catalogues, and many of these objects are optically variable. It is
important to note that visual or spectroscopic binary companions can
rarely be ruled out as the source of EUV emission.
Note (2):
The column headed "comments" contains information regarding the
counterparts as detailed below:
E: Exosat detection within WFC error circle.
I: IUE target within WFC error circle (not necessarily a detection).
pm: High proper motion star, from the Luyten catalogue of stars with
proper motions >0.5 arcseconds per year (Luyten, 1976).
N: Nearby stars, from the Gliese and Jahreiss (1969,1979,1991) catalogues.
A: Active star or star system (mostly from the Strassmeier et al.
catalogue of chromospherically active binary stars). The "A" flag
is not given for RS CVn and BY Dra systems, or where the spectral
type indicates emission (e.g. dMe).
(B): The most probable counterpart is a known binary, or has one or more
sources nearby, within the error circle, with the same name, but a
different qualifying letter at the end, usually implying a visual
binary or multiple star system. The source(s) of EUV emission are not
always clear in these cases.
V*: Variable star, from the general catalogue of variable stars (GCVS),
either directly or via the SIMBAD database.
EI: Einstein IPC detection within WFC error circle.
H: Einstein HRI detection within WFC error circle.
N(H)= Interstellar hydrogen absorption column, in units of 10^20 cm-2,
estimated from the maps of Stark et al. (1992; available for
delta> -40deg) for extragalactic counterparts within the error
circles. Generally we do not expect to detect extragalactic sources
through a column greater than N(H)∼2.
(C): Designates another counterpart in the error circle, which has the
same name, but different extension letter to the first counterpart.
b: Blue star, generally from the master list of non-stellar sources (Dixon,
1970), or from references given in the SIMBAD database.
HEAO: HEAO-A1 detection (Wood et al., 1984).
IDP: ROSAT WFC optical identification programme (Mason et al., 1992) with
activity/non-activity represented by "A" and "nonA" respectively.
"IDPn" indicates no identification yet found from spectroscopic search
of EUV error circle. The final three columns in Table 1 give the WFC 90%
confidence position error circle radius (arcsecs); the counterpart
offset from the EUV source position (arcsecs), and the catalogue from
which the counterpart position was taken. Sources for which there is
note below are marked with a "R" symbol at the end of the entry. The
catalogue names are abbreviated as listed below (following notes on
individual sources).
Notes on individual sources ('R' in column 129):
RE 0044+093: New fast rotating single star radio source
(Bromage et al., in preparation).
RE 0116-022: AY Cet is an active close binary with a WD companion
(Strassmeier et al., 1988) and a 57 day orbit. The WD
is not expected to contribute to the EUV flux.
RE 0415-073: 40 Eri emission was resolved with the Einstein HRI, most emission
coming from 40 Eri C, the dMe flare star (Cash et al., 1980).
All three components could be contributing to the EUV flux.
RE 0447-275: Identification is with a newly discovered dMe star, the fainter
companion of a close visual pair; this has subsequently been
discovered to be a flare star (Bromage, 1992).
RE 0515+324: Identified with a white dwarf, coincident with the 8th magnitude,
A2/F4V star HD 33959C. An IUE SWP spectrum of this star shows
a rise towards short wavelengths, indicative of a hot white dwarf
companion (Hodgkin et al., 1992). Other catalogued stars in
the WFC error circle include the 5th magnitude A9IV star KW Aur,
and the 11th magnitude star BD+32 922B, which are both
unlikely to contribute to the detected EUV flux.
RE 0532-030: Star identified may be HBC97 (dKe) but this association is
uncertain because of position discrepancies.
RE 0604-343: The S2 filter count rate was enhanced by a flare; this is a new
dMe flare star. See Bromage (1992).
RE 0604-482: HD 41824 is a very close visual binary. Star A (G? V) has no
reported variations in radial velocity or photometry whereas star
B (G6V) has variable RV and photometric variability. Following
the IDP discovery of chromospheric activity (Mason et al., 1992)
it seems very likely that star B is the EUV emitter and is
probably an SB1 RSCVn binary.
RE 0631+500: The dMe star discovered in the optical identification programme
now appears (but not named) in the latest version of the Gliese
catalogue (1991) as an M0 star with V=11.09 mag.
RE 0734+315: YY Gem is an eclipsing binary double-flare star. The S2 filter
count rate was enhanced by a flare event on 1990 Oct 03
(Bromage, 1992).
RE 0751+144: Identified as new intermediate polar system (Mason et al., 1992b).
RE 0827+284: Identified with the hot, evolved star PG 0824+289, classified as a
subdwarf in the Palomar Green survey
(Green et al., 1986 - hereafter PG), and more recently shown to
be a hot DA white dwarf (Sansom et al., 1992).
RE 0838-430: This WFC detection is part of the Vela SNR. There is also a 9th
magnitude K giant in the WFC error circle, which is likely to be
a chance coincidence.
RE 1016-052: This is a newly discovered Feige-24 type DA+dMe binary
(Jomaron et al., 1992).
RE 1043+445: Identified with the hot, evolved star PG 1040+451, classified as a
hot subdwarf (sdB) in the PG survey and more recently shown to be
a possible hot DA white dwarf (Sansom et al., 1992). Because of
the low signal-to-noise data the optical classification of this
star is still uncertain, as indicated by the colon after the
spectral type in table 1.
RE 1104+381: Identified with the BL Lac object Mrk 421. The DC white dwarf also
in the EUV source error circle is probably too cool to be detected.
RE 1111-224: Positionally coincident with the 4th magnitude, A2 IV star beta
Crt, the likely source of EUV emission has been shown to be a
DA white dwarf companion beta Crt B (Fleming et al., 1991),
which is a spectroscopic binary companion to beta Crt.
RE 1149+284: Identified as probable new AM Her system (Mittaz et al., 1992).
RE 1236+475: Identified with the hot, evolved star PG 1234+482, classified as a
hot subdwarf (sdOB) in the PG survey, and more recently shown to
be a hot DA white dwarf (Jordan et al., 1991, Sansom et al., 1992).
RE 1255+255: The variable star IN Com, within the WFC error circle, is very
close to the centre of the planetary nebula LT5. IN Com is a
triple system consisting of an 8.7th magnitude, G5 III star with
active chromosphere and a low mass, binary companion, plus an
outer, hot subdwarf (Malasan et al., 1991). The G star is the
most likely source of EUV emission, but emission from the other
components cannot be ruled out.
RE 1307+535: Identified as probable new AM Her system, with the shortest known
period in the class (Osborne et al., 1992).
RE 1428+424: Identified with a BL Lac; first seen by HEAO-1 and later optically
identified by Remillard et al. (1989).
RE 1603-574: iota Nor consists of a group of several 5th magnitude mid-A
stars within approx 2 arcsec (SAO 243279: IDS 15554-1570AB). The
star SAO 243278 (IDS 15554-1570C) approximately 10 arcsec away has
now been shown to be a 6-day period double-lined spectroscopic
binary active G star and candidate RSCVn binary (Bromage, 1992).
RE 1625-490: The optical identification has been made independently by
Cutispoto et al. (1992) from an optical follow up programme of
serendipitous EXOSAT sources; the object does not show any
evidence of binarity.
RE 1629+780: This is a newly discovered Feige-24 type DA+dMe binary (Cooke et
al., 1992).
RE 1800+683: Identified with the hot, evolved star KUV 18004+6836, classified
as a hot subdwarf (sdB) by Wegner et al. (1987), and more recently
shown to be a hot DA white dwarf (Sansom et al., 1992).
RE 1833+514: The famous prototype of the BY Dra class of spotty active stars;
the S2 flux was enhanced by a flare (Barstow et al., 1991).
RE 1938-461: Identified as new AM Her system (Buckley et al., 1992).
RE 2045-312: AU Mic, a well known flare star. The S1 flux was enhanced by a
flare (Bromage, 1992).
RE 2047-363: A newly discovered very fast rotating single dwarf star, nicknamed
"Speedy Mic" (Bromage et al., 1992). The S2 flux was enhanced by
a long-lived flare, and variability of activity occurred in
both filters.
RE 2147-160:delta Cap: the visual companions of this 3rd magnitude peculiar A
star binary have been ruled out as possible EUV counterparts by
CCD photometry and high-resolution spectroscopy, leaving the
likely counterpart as the hidden binary companion of delta Cap
itself (probably a mildly active late type star).
(Wonnacott et al., 1992).
RE 2157-505: Gliese B41A: newly identified as an SB2 binary dMe flare star; the
common proper-motion WD companion is too cool to contribute to
the EUV flux, but the derived age of the system makes G1841A one
of the oldest known active star systems
(Jeffries and Bromage, 1992).
RE 2246+442: The well-known flare star EV Lac. Both S1 and S2 filter fluxes
were enhanced by flares during the survey coverage (Bromage, 1992).
See also:
J/ApJS/93/569 : the first EUVE Catalog (Bowyer et al. 1994)
II/203 : the second EUVE Catalog (Bowyer et al., 1996)
J/MNRAS/274/1165 : the 2RE Catalog (Pye et al. 1995)
J/A+AS/114/465 : the ROSAT XUV Pointed Phase Source Catalog
(Kreysing et al. 1995)
Acknowledgments:
Thanks are due to Dr Mike Watson for e-mailing the LaTeX files.
"DeTeX" was performed at CDS, and the insertion of the 'J' for
truncated IAU-style designation was added in the text.
(End) Francois Ochsenbein [CDS] 29-May-1993