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J/A+A/521/A45   X-ray detections in the σ Ori cluster  (Caballero+, 2010)

HRC-I/Chandra X-ray observations towards σ Orionis. Caballero J.A., Albacete-colombo J.F., Lopez-Santiago J. <Astron. Astrophys., 521, A45-45 (2010)> =2010A&A...521A..45C
ADC_Keywords: Clusters, open ; Stars, early-type ; X-ray sources Keywords: brown dwarfs - stars: early-type - stars: flare - stars: variables: T Tauri, Herbig Ae/Be - X-rays: stars - open clusters and associations: individual: σ Orionis Abstract: We investigated the X-ray emission from young stars and brown dwarfs in the σ Orionis cluster (τ≃3Ma, d≃385pc) and its relation to mass, the presence of circumstellar discs, and separation to the cluster centre by taking advantage of the superb spatial resolution of the Chandra X-ray Observatory. Description: We used public HRC-I/Chandra data from a 97.6ks pointing towards the cluster centre and complemented them with X-ray data from IPC/Einstein, HRI/ROSAT, EPIC/XMM-Newton, and ACIS-S/Chandra together with optical and infrared photometry and spectroscopy from the literature and public catalogues. On our HRC-I/Chandra data, we measured count rates, estimated X-ray fluxes, and searched for short-term variability. We also looked for long-term variability by comparing with previous X-ray observations. File Summary:
FileName Lrecl Records Explanations
ReadMe 80 . This file tablec1.dat 72 107 HRC-I/Chandra X-ray detections with significance over 5.1. tablec2.dat 87 90 Optical/near-infrared counterparts of X-ray sources in Table C1 tablec3.dat 99 63 A reappraisal to the X-ray sources near σ Ori in Wolk (1996, Ph.D. Thesis)
See also: J/AN/325/705 : RIJHKs of low-mass stars in σ Ori (Bejar+, 2004) J/A+A/419/249 : RJHKs photometry of σ Ori low-mass stars (Scholz+, 2004) J/A+A/446/501 : XMM observations of σ Ori cluster (Franciosini+, 2006) J/A+A/493/931 : MAD observations of σ Ori (Bouy+, 2009) J/ApJ/688/362 : Disks around brown dwarfs in σ Ori (Luhman+ 2008) J/ApJS/191/389 : Photometric monitoring in σ Ori cluster (Cody+, 2010) J/MNRAS/356/89 : σ Ori low-mass stars (Kenyon+, 2005) B/chandra : The Chandra Archive Log (CXC, 1999-) Byte-by-byte Description of file: tablec1.dat
Bytes Format Units Label Explanations
1- 3 I3 --- Seq [1/107] Sequential number 5- 6 I2 h RAh Right ascension (J2000) 8- 9 I2 min RAm Right ascension (J2000) 11- 15 F5.2 s RAs Right ascension (J2000) 17 A1 --- DE- Declination sign (J2000) 18- 19 I2 deg DEd Declination (J2000) 21- 22 I2 arcmin DEm Declination (J2000) 24- 27 F4.1 arcsec DEs Declination (J2000) 29- 32 F4.2 arcsec e_Pos Position error 34- 39 F6.2 --- Signi Significance of detection 41- 45 F5.2 arcmin Offaxis Angular separation to the centre of field of view 47- 52 F6.2 ct/ks CR Count rate 54- 57 F4.2 ct/ks e_CR rms uncertainty on CR 59- 64 F6.2 10-17W/m2 Flux Apparent X-ray flux (10-14erg/cm2/s) 66- 68 I3 --- NX ?=- Source number in Franciosini et al, 2006, Cat. J/A+A/446/501, <[FPS2006] NX NNN> in Simbad 69 A1 --- n_NX [)<] Uncertain or non-detection (1) 71- 72 I2 --- CXO ?=- Source number in Skinner et al. 2008ApJ...683..796S, <[SSC2008] NN> in Simbad
Note (1): Note as follows: ) = uncertainty identification < = sources not detected by Franciosini et al. (2006, Cat. J/A+A/446/501) for which the authors provided EPIC count-rate upper levels
Byte-by-byte Description of file: tablec2.dat
Bytes Format Units Label Explanations
1- 3 I3 --- Seq [1/107] Sequential number 5- 20 A16 --- 2MASS 2MASS name (HHMMSSss+DDMMSSs) 22- 40 A19 --- Name Name 43- 65 A23 --- AName Alternative name 68- 87 A20 --- Class Classification (2)
Note (2): classes are: Young brown dwarf ; Young star; Young star candidate ; Field star ; Possible field star ; Galaxy
Byte-by-byte Description of file: tablec3.dat
Bytes Format Units Label Explanations
1- 12 A12 --- Source Source name (1) 14- 15 I2 h RAh Wolk 1996 Right ascension (J2000) 17- 18 I2 min RAm Wolk 1996 Right ascension (J2000) 20- 23 F4.1 s RAs Wolk 1996 Right ascension (J2000) 25 A1 --- DE- Wolk 1996 Declination sign (J2000) 26- 27 I2 deg DEd Wolk 1996 Declination (J2000) 29- 30 I2 arcmin DEm Wolk 1996 Declination (J2000) 32- 33 I2 arcsec DEs Wolk 1996 Declination (J2000) 35- 40 F6.2 ct/ks CR Count rate 42- 45 F4.2 ct/ks e_CR rms uncertainty on CR 47- 50 A4 --- SpT MK spectral type 51 A1 --- n_SpT [x] when star spectroscopically investigated by Wolk (1996 PhD thesis) but spectral type not given 53- 54 I2 h RA2h ? 2MASS Right ascension (J2000) 56- 57 I2 min RA2m ? 2MASS Right ascension (J2000) 59- 63 F5.2 s RA2s ? 2MASS Right ascension (J2000) 65 A1 --- DE2- 2MASS Declination sign (J2000) 66- 67 I2 deg DE2d ? 2MASS Declination (J2000) 69- 70 I2 arcmin DE2m ? 2MASS Declination (J2000) 72- 75 F4.1 arcsec DE2s ? 2MASS Declination (J2000) 77- 78 I2 --- NX ? Source number in Franciosini et al, 2006, Cat. J/A+A/446/501, <[FPS2006] NX NNN> in Simbad 80- 99 A20 --- Name Alternate name
Note (1): RHHMMSS-DDMM identified as <[W96] rJHHMMSS-DDMM> in Simbad NNNN NNNN identified as <[W96] NNNN-NNNN> in Simbad
History: From electronic version of the journal
(End) Patricia Vannier [CDS] 03-Feb-2011
The document above follows the rules of the Standard Description for Astronomical Catalogues.From this documentation it is possible to generate f77 program to load files into arrays or line by line

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