J/A+AS/114/109 Cha X-ray sources & optical identifications (Alcala+ 1995)
A study of the Chamaeleon star forming region from the ROSAT all-sky survey.
I. X-ray observations and optical identifications
Alcala J.M., Krautter, J., Schmitt J.H.M.M., Covino E., Wichmann R.,
Mundt R.
<Astron. Astrophys. Suppl. Ser. 114, 109 (1995)>
=1995A&AS..114..109A 1995A&AS..114..109A (SIMBAD/NED BibCode)
ADC_Keywords: X-ray sources ; QSOs
Mission_Name: ROSAT
Keywords: X-ray: stars - stars: pre-main-sequence - ISM: Chamaeleon clouds -
Surveys
Description:
We present the observations of the ROSAT all-sky survey (RASS) in the
direction of the Chamaeleon cloud complex, as well as the
spectroscopic identifications of the detected X-ray sources. The main
purpose of this identification program was the search for low mass
pre-main sequence stars. Sixteen previously known PMS stars were
detected with high confidence by ROSAT. Eight are classical T Tauri
stars and eight are weak-line T Tauri stars. Seventy-seven new
weak-line T Tauri stars were identified on the basis of the presence
of strong Li λ6707 absorption, spectral type later than F0 and
chromospheric emission. We give coordinates and count rates of the
X-ray sources, and present optical spectra and finding charts for the
sources identified optically as new pre-main sequence stars. Optical
UBV(RI)c and near-infrared JHKLM photometry for this sample of stars
is also provided. In addition, 6 new dKe-dMe candidates are found
among the RASS sources.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table6 95 180 ROSAT all-sky survey X-ray sources in Chamaeleon
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See also:
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1996)
Byte-by-byte Description of file: table6
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Bytes Format Units Label Explanations
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1- 11 A11 --- RXJ RXJ X-ray source name
12 A1 --- m_RXJ Multiplicity index on RXJ
15- 16 I2 h RAh Right ascension (J2000)
18- 19 I2 min RAm Right ascension (J2000)
21- 25 F5.2 s RAs Right ascension (J2000)
28 A1 --- DE- Declination sign
29- 30 I2 deg DEd Declination (J2000)
32- 33 I2 arcmin DEm Declination (J2000)
35- 38 F4.1 arcsec DEs Declination (J2000)
41- 45 F5.3 ct/s Count Count rates from ROSAT
47- 51 F5.3 ct/s e_Count rms uncertainty on Count
53- 64 A12 ---- ID Optical identification
66- 67 I2 arcsec Theta ? Offset distance
70- 74 A5 --- SpType Spectral type
77- 80 A4 --- Type Type (1)
82- 86 A5 --- Note Appearance in finding chart
88 A1 --- n_Note Note (2)
90- 95 A6 --- Ref References (3)
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Note (1): W : previously known weak-line T Tauri star
C : previously known classical T Tauri star
Wn : new weak-line T Tauri star
UAS: unrelated active star
UBS: unrelated bright star
IR : infrared source
QS : quasar
RS : radio source
G : galaxy.
Note (2): St.: Stellar, Gal.: galaxy, faint: object fainter than V∼20.
a : source investigated spectroscopically, but without stellar
counterpart found.
b : source not investigated. Its corresponding error circle contains
objects fainter than our limit for the spectroscopic
observations (V∼17mag).
c : very strong spectroscopic and photometric variability
(Alcala et al. 1993A&A...272..225A 1993A&A...272..225A).
d : Halpha filled-in with emission but no Li I A6707 absorption.
e : Li I lambda6707 absorption to be confirmed because of low S/N of
the spectrum.
Note (3): 1: this Work
2: Simbad catalogue (see ROSAT PSPC, Cat. IX/11)
3: Gauvin and Strom (1992ApJ...385..217G 1992ApJ...385..217G)
4: Feigelson and Kriss (1989ApJ...338..262F 1989ApJ...338..262F)
5: Hyland et al. (1982MNRAS.201.1095H 1982MNRAS.201.1095H)
6: Hughes and Hartigan (1992AJ....104..680H 1992AJ....104..680H)
7: Walter (1992AJ....104..758W 1992AJ....104..758W)
8: Feigelson et al. (1993ApJ...416..623F 1993ApJ...416..623F)
9: Huenemoerder et al. (1994MNRAS.271..967H 1994MNRAS.271..967H)
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History: Prepared via OCR at CDS.
(End) James Marcout, Patricia Bauer [CDS] 25-Oct-1996