J/A+A/298/115 ROSAT study of Praesepe (Randish+, 1995)
A ROSAT X-ray study of the Praesepe cluster
Randich S., Schmitt J.H.M.M.
<Astron. Astrophys. 298, 115 (1995)>
=1995A&A...298..115R 1995A&A...298..115R (SIMBAD/NED Reference)
ADC_Keywords: Clusters, open; X-ray sources
Keywords: open cluster and associations: individual (Praesepe) -
stars: coronae - X-ray: stars
Description:
We present the results of the ROSAT PSC observations of the Praesepe
cluster. 68 Praesepe candidates have been detected, above a threshold
of ∼2x10+28erg/s (2x1021W), in the ∼4degx4deg area of the cluster
covered by the observations. 56 out of the 68 detected objects are
cataloged as high probability Praesepe members.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2 100 68 Optical properties of X-ray detected Praesepe
candidates
table4 63 68 X-ray properties of the detected Praesepe
candidates
table5 57 12 Undetected Praesepe candidates lying in the
low sensitivity image region
table2.tex 86 171 LaTeX version of table2
table4.tex 107 122 LaTeX version of table4
table5.tex 72 44 LaTeX version of table5
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Byte-by-byte Description of file: table2
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Bytes Format Units Label Explanations
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2- 3 I2 --- Id [1/68] X-ray number
10- 15 A6 --- OtherId Optical identification (1)
21- 22 I2 h RAh Right ascension J2000
24- 25 I2 min RAm Right ascension J2000
27- 31 F5.2 s RAs Right ascension J2000
37 A1 --- DE- Declination sign
38- 39 I2 deg DEd Declination J2000
41- 42 I2 arcmin DEm Declination J2000
44- 47 F4.1 arcsec DEs Declination J2000
49- 53 F5.2 mag Vmag V magnitude
56- 59 F4.2 mag B-V []? B-V colour
62- 65 F4.2 mag V-I []? V-I colour
69- 70 I2 % Proba []? Membership probability
71 A1 --- n_Proba [p] A 'p' means possible
74- 79 A6 --- Sp Spectral type
82-101 A20 --- Notes Notes
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Note (1): KW: Klein-Wassink (1927)
JC: Jones & Cudworth (1983)
JS: Jones & Stauffer (1991)
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Byte-by-byte Description of file: table4
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Bytes Format Units Label Explanations
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2- 3 I2 --- Id X-ray number
4 A1 --- n_Id [*] Note
8- 12 F5.1 --- ML Maximum Likelihood (ML) algorithm
14- 19 F6.2 arcsec dRA []? Offset in right ascension
21- 26 F6.2 arcsec dDE []? Offset in declination
28- 33 F6.4 ct/s ct Counts
35- 40 F6.4 ct/s e_ct rms uncertainty on counts (1 sigma error)
42- 45 F4.1 10+22W Lx X-ray luminosity
47- 49 F3.1 10+22W e_Lx rms uncertainty on Lx (1 sigma error)
51- 56 E6.2 --- Lx/Lbol X-ray over bolometric luminosity
58 A1 --- l_HardR [>] limit flag on HardR
59- 63 F5.2 --- HardR Hardness ratio
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Byte-by-byte Description of file: table5
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Bytes Format Units Label Explanations
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1- 6 A6 --- Name Star name
8- 9 I2 h RAh Right ascension J2000
11- 12 I2 min RAm Right ascension J2000
14- 17 F4.1 s RAs Right ascension J2000
18 A1 --- DE- Declination sign
19- 20 I2 deg DEd Declination J2000
22- 23 I2 arcmin DEm Declination J2000
25- 26 I2 arcsec DEs Declination J2000
28- 32 F5.2 mag V V magnitude
34- 37 F4.2 mag B-V []? B-V colour
40- 43 F4.2 mag V-I []? V-I colour
45- 46 I2 % Proba Membership probability
48- 53 F6.4 ct/s Upct Upper limit on counts
55- 57 F3.1 10+22W Lx Upper limit on X-ray luminosity (1029erg/s)
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References:
Klein-Wassink W.J. 1927, Publ. Kepyen Astron. Lab. Nr 41
Jones B.F., Cudworth K., 1983, AJ 88, 215
Jones B.F., Staufer J.R. 1991, AJ 102, 1080
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(End) Patricia Bauer [CDS] 24-Nov-1994