J/A+A/406/535 Hamburg/RASS Cat. of optical ident. V3.0 (Zickgraf+, 2003)
The Hamburg/RASS Catalogue of optical identifications.
Northern high-galactic latitude ROSAT Bright Source Catalogue X-ray sources.
Zickgraf F.-J., Engels D., Hagen H.-J., Reimers D., Voges W.
<Astron. Astrophys. 406, 535 (2003)>
=2003A&A...406..535Z 2003A&A...406..535Z
ADC_Keywords: X-ray sources ; Galaxy catalogs ; QSOs ; Cross identifications
Keywords: surveys - X-rays: general - X-rays: galaxies - X-rays: stars -
galaxies: active - galaxies: clusters: general
Abstract:
We present the Hamburg/RASS Catalogue (HRC) of optical identifications
of X-ray sources at high-galactic latitude. The HRC includes all X-ray
sources from the ROSAT Bright Source Catalogue (RASS-BSC) with
galactic latitude |b|≥30° and declination DE≥0°. In this
part of the sky covering ∼10 000 deg2 the RASS-BSC contains 5341
X-ray sources. For the optical identification we used blue Schmidt
prism and direct plates taken for the northern hemisphere Hamburg
Quasar Survey (HQS) which are now available in digitized form. The
limiting magnitudes are 18.5 and 20, respectively. For 82% of the
selected RASS-BSC an identification could be given. For the rest
either no counterpart was visible in the error circle or a plausible
identification was not possible. With ∼42% AGN represent the largest
group of X-ray emitters, ∼31% have a stellar counterpart, whereas
galaxies and cluster of galaxies comprise only ∼4% and ∼5%,
respectively. In ∼3% of the RASS-BSC sources no object was visible on
our blue direct plates within 40" around the X-ray source position.
The catalogue is used as a source for the selection of (nearly)
complete samples of the various classes of X-ray emitters.
Description:
This is the Version 3.0, issued May 6, 2003, 5341 X-ray sources from
the ROSAT-BSC
Version 2.0, issued January 5, 1998 now 4665 positions,
(Bade et al., 1998, Cat. J/A+AS/127/145)
Version 1.1, issued December 5, 1996 additional entries in the X-ray rows
(flags and date of last change)
Version 1.0, issued November 1, 1996
The catalogue can be used for scientific purposes if the above
mentioned paper is referenced.
For more detailed information about the identification code and the
classification scheme for objective prism spectra the catalogue user
is also referred to this paper.
Acknowledgements:
The ROSAT project is supported by the Ministerium fuer Bildung,
Wissenschaft, Forschung und Technologie (BMBF/DARA) and by the
Max-Planck-Gesellschaft (MPG).
This research has made use of the NASA/IPAC Extragalactic Database
(NED) which is operated by the Jet Propulsion Laboratory, California
Institute of Technology, under contract with the National Aeronautics
and Space Administration.
This work has been funded by the Deutsche Forschungsgemeinschaft under
Re 353/22-1 to 4 and by the BMBF under DARA 50 0R 96016.
The STScI Digitized Sky Surveys were produced at the Space Telescope
Science Institute under U.S. Government grant NAG W-2166. The images
of these surveys are based on photographic data obtained using the
Oschin Schmidt Telescope on Palomar Mountain and the UK Schmidt
Telescope. The plates were processed into the present compressed
digital form with the permission of these institutions.
The National Geographic Society - Palomar Observatory Sky Atlas
(POSS-I) was made by the California Institute of Technology with
grants from the National Geographic Society.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
x-ray.dat 135 5341 X-ray data
optical.dat 107 13829 Optical data
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See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)
J/A+AS/127/145 : Hamburg/RASS Cat. of optical identifications, HRC (Bade+ 1998)
Byte-by-byte Description of file: x-ray.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [1RXS]
6- 21 A16 --- 1RXS Object name, 1RXS JHHMMSS.s+DDMMSS
23- 28 F6.3 ct/s RASSCR RASS count rate
30- 34 F5.3 ct/s e_RASSCR Error of count rate
36- 40 F5.2 --- HR1 Hardness ratio HR1 (1)
42- 45 F4.2 --- e_HR1 Error of HR1
47- 51 F5.2 --- HR2 Hardness ratio HR2 (1)
53- 56 F4.2 --- e_HR2 Error of HR2
58- 60 I3 arcsec Ext Source extension
62- 65 I4 --- L_Ext Source extension likelihood
67- 68 A2 --- --- [RX]
70- 81 A12 --- RX RASS name, RX JHHMM.m+DDMM, as used in the
first catalogue version
84- 85 I2 h RAh Right ascension (J2000.0)
87- 88 I2 min RAm Right ascension (J2000.0)
90- 93 F4.1 s RAs Right ascension (J2000.0)
96 A1 --- DE- Declination sign (J2000.0)
97- 98 I2 deg DEd Declination (J2000.0)
100-101 I2 arcmin DEm Declination (J2000.0)
103-104 I2 arcsec DEs Declination (J2000.0)
106-107 I2 arcsec errPos Error radius derived from the BSC
109-115 A7 --- Seq Internal number of the HRC data base
117-119 I3 --- Code Type of source identification code (2)
121 I1 --- Flag1 [0/1]? 1: identification changed since last
catalogue version
122 I1 --- Flag2 [0/1]? 1: entries to this X-ray position
have changed since last catalogue version
123 I1 --- Flag3 [0/1]? 1: supplementary X-ray positions
125-134 A10 "YYYY/MM/DD" Date ? Date of last change (3)
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Note (1): The hardness ratio are defined as:
HR1=B-A/B+A and HR2=D-C/D+C, where
A is the count rate in 0.11-0.41keV energy band,
B is the count rate in 0.52-2.01keV energy band,
C is the count rate in 0.52-0.90keV energy band,
D is the count rate in 0.91-2.01keV energy band,
Note (2): The identification code is defined as follows:
The first (and third) digit give(s) the classification:
1 AGN
2 Galaxy, derived from the morphology on the direct plates
3 Cluster
5 M dwarf
6 White Dwarf
7?1 K Dwarf
7?2 F or G star
7?3 Cataclysmic Variable (CV)
7?4 Bright Star (B < 13)
8 no plausible candidate found
803 one object in favourable position, but no spectral information
0 empty field on objective prism and direct plate within a radius
of at least 40 arcsec
The second digit in the identification code describes the reliability
of the given identification:
0 'highly probable', the proposed counterpart fulfills all
requirements of its class and no other plausible counterpart
within the error radius of the X-ray source exists
1 'probable', the proposed counterpart fulfills the requirements of
its class, but there are limitations. Either, the objective
spectrum is not typical, or there are small conflicts with the
X-ray information (spectral or spatial information, distance to
the X-ray position) or there is another (considerably less)
plausible counterpart in the error circle
2 'possible', the proposed counterpart fulfills some requirements
of its class, but there are doubts arising from insufficient
objective prism data, conflicting X-ray data or another
plausible candidate
Note (3): For 1RXS J123516.9+233447, the last digit of the Date was missing,
and replaced by 0.
For 1RXS J081929.5+704221, and there is no Flags and Date.
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Byte-by-byte Description of file: optical.dat
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Bytes Format Units Label Explanations
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1- 2 A2 --- --- [RX]
4- 15 A12 --- RX Name of the X-ray source
18 A1 --- OC [+] + for proposed optical counterpart
19- 20 I2 --- NOpt Running number of objects visible in the
error circle ([ZEH2003] RX JHHMM.m+DDMM NN>)
21 A1 --- n_NOpt [P]
23- 24 I2 h RAh ? Right ascension (J2000.0)
26- 27 I2 min RAm ? Right ascension (J2000.0)
29- 32 F4.1 s RAs ? Right ascension (J2000.0)
35 A1 --- DE- Declination sign (J2000.0)
36- 37 I2 deg DEd ? Declination (J2000.0)
39- 40 I2 arcmin DEm ? Declination (J2000.0)
42- 43 I2 arcsec DEs ? Declination (J2000.0)
46- 49 I4 arcsec oRA X-ray position - optical position
in right ascension
52- 55 I4 arcsec oDE X-ray position - optical position in declination
59- 61 I3 arcsec rXO Distance between X-ray and optical position
65 A1 --- l_Bmag Limit flag on Bmag (1)
66- 69 F4.1 mag Bmag ? Optical magnitude B
(no entry means no B magnitude available)
70 A1 --- n_Bmag [uep:] Note on Bmag (2)
72- 75 F4.1 mag B-R ? B-R colour index from USNA-A 2.0
Catalog (I/252)
81- 89 A9 --- Class Classification from objective prism spectrum (3)
90-102 A13 --- Note Note when no position
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Note (1): A '<' means upper limit for magnitude, the object is saturated
Bmag='>19.0' means that the optical counterpart is only visible
on the direct plate not on the prism plate(s)
Note (2): Note on Bmag:
'u' means that the magnitude is taken form the USNO (I/252)
'e' means "extended image"
'p' not defined in the original data
':' means uncertainty
Note (3): For the classification of objective prism spectra the
following scheme was adopted:
SUBDWARF Hot Subdwarfs (sdO,sdB)
W-DWARF White Dwarfs
STAR-BA Balmer absorption lines, point-like image
STAR-FG G-Band, Ca H+K, point-like image
STAR-K G-Band, Ca H+K, redder continuum, point-like image
STAR-M Very red, TiO lines, Ca I 4226, point-like image
CV Cataclysmic variable, Balmer emission lines
GALAXY Extended image on direct plate, no emission lines, red continuum
AGN Emission line(s), blue continuum, weak extension on direct
plate allowed
BLUE GAL moderately blue continuum, extended image on direct plate
QSO Emission line(s), extremely blue continuum, no extension
on direct plate
EBL-WK Extremely blue continuum, weak point-like object
BLUE-WK Moderately blue continuum, weak point-like object
RED-WK Red continuum, weak point-like object
UNIDENT Classification open
OVERLAP Classification not possible due to overlapping spectra
SATURATE Classification not possible due to amplifier saturation
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History:
Copied at ftp://ftp.hs.uni-hamburg.de/pub/outgoing/rass-id/
(End) James Marcout, Patricia Bauer [CDS] 22-Sep-2003