J/A+A/506/1055 Hot stars emitting in X-ray. I. (Naze, 2009)
Hot stars observed by XMM-Newton. I. The catalog and the properties of OB stars.
Naze Y.
<Astron. Astrophys. 506, 1055 (2009)>
=2009A&A...506.1055N 2009A&A...506.1055N
ADC_Keywords: X-ray sources ; Stars, early-type
Keywords: X-rays: stars - stars: early-type - catalogs
Abstract:
Following the advent of increasingly sensitive X-ray observatories,
deep observations of early-type stars became possible. However, the
results for only a few objects or clusters have until now been
reported and there has been no large survey comparable to that based
upon the ROSAT All-Sky Survey (RASS). A limited survey of X-ray
sources, consisting of all public XMM observations (2XMMi) and slew
survey data (XMMSL1), is now available. The X-ray counterparts to hot,
massive stars have been searched for in these catalogs. About 300 OB
stars were detected with XMM. Half of them were bright enough for a
spectral analysis to be possible, and we make available the detailed
spectral properties that were derived. The X-ray spectra of O stars
are represented well by low (<1keV) temperature components and seem to
indicate that an absorption column is present in addition to the
interstellar contribution. The X-ray fluxes are well correlated with
the bolometric fluxes, with a scatter comparable to that of the RASS
studies and thus larger than found previously with XMM for some
individual clusters. These results contrast with those of B stars that
exhibit a large scatter in the LX-LBOL relation, no additional
absorption being found, and the fits indicate a plasma at higher
temperatures. Variability (either within one exposure or between
multiple exposures) was also investigated whenever possible:
short-term variations are far more rare than long-term ones (the
former affects a few percent of the sample, while the latter concerns
between one third and two thirds of the sources).
Description:
Table 1 is a catalog of X-ray emitters amongst early-type stars
following a correlation between the Reed and 2XMMi catalogs - note
that line 1 summarizes the column info, lines 2, 38, 130 gives a title
for the O, B, and WR stars with good quality flag and lines 138, 237
and 308 do the same for sources with possibly spurious sources. In
each category (O/B/WR + good/spurious), the sources are ranked by
increasing RA. Table 5 gives the spectral properties of the brightest
sources (models of the type wabs(interstellar)*wabs(additional)*sum of
3 mekal max. Undetermined values are quoted as "---".
See paper for more details.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 444 310 Hot stars detected in the 2XMMi
table5.dat 332 332 Spectral properties of detected hot stars
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See also:
V/125 : Photometry and Spectroscopy for Luminous Stars (Reed 2005)
IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)
IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)
IX/37 : XMM-Newton Serendipitous Source Catalogue (1XMM) (XMM-SSC, 2003)
IX/40 : XMM-Newton 2nd Incremental Source Catalogue (2XMMi) (XMM-SSC, 2008)
B/xmm : XMM-Newton Observation Log (XMM-Newton SOC, 2009)
J/A+A/619/A148 : Hot stars observed by XMM-Newton. II. (Naze+, 2018)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 I1 --- Cl [1/6] quality / spectral class code (1)
2 A1 --- Pair [a-e] Identification of the same members of
a pair (2)
3- 26 A24 --- Query Name or coord. used to query the 2XMMi catal.
28- 32 I5 --- ALS ID Number in Reed catalog (V/125)
36- 59 A24 --- Name Usual name of the source
61- 79 A19 --- SpType MK Spectral type (3)
81 A1 --- Bin [Y] Binary if set to Y (=yes)
85 A1 --- Simb [~] ∼ if taken from Simbad
86- 90 F5.2 mag Vmag ?=- V magnitude
92- 96 F5.2 mag B-V ?=- B-V colour index
98-105 E8.2 cm-2 N(H,int) ?=- Interstellar absorption column
107-111 F5.2 [mW/m2] logFbol ?=- Logarithm of the bolometric flux (4)
113-115 F3.1 arcsec Dist Distance between X-ray source and star
118-133 A16 --- 2XMM IAU name of the 2XMM(i) source
135-144 A10 --- Filtpn Filter used for EPIC-pn
146-155 A10 --- FiltM1 Filter used for EPIC-MOS1
157-166 A10 --- FiltM2 Filter used for EPIC-MOS2
168-177 E10.4 ct/s CRpn ?=- Count rate in 0.5-4.5keV for pn
179-188 E10.4 ct/s e_CRpn ?=- Error on the pn count rate
190-199 E10.4 ct/s CRM1 ?=- Count rate in 0.5-4.5keV for MOS1
201-210 E10.4 ct/s e_CRM1 ?=- Error on the MOS1 count rate
212-221 E10.4 ct/s CRM2 ?=- Count rate in 0.5-4.5keV for MOS2
223-232 E10.4 ct/s e_CRM2 ?=- Error on the MOS2 count rate
234-239 F6.3 --- HR1pn ?=- HR1 for EPIC-pn (5)
242-246 F5.3 --- e_HR1pn ?=- Error on pn HR1
248-253 F6.3 --- HR2pn ?=- HR2 for EPIC-pn (5)
256-260 F5.3 --- e_HR2pn ?=- Error on pn HR2
262-267 F6.3 --- HR3pn ?=- HR3 for EPIC-pn (5)
270-274 F5.3 --- e_HR3pn ?=- Error on pn HR3
276-281 F6.3 --- HR4pn ?=- HR4 for EPIC-pn (5)
283-292 F10.3 --- e_HR4pn ?=- Error on pn HR4
294-299 F6.3 --- HR1M1 ?=- HR1 for EPIC-MOS1 (5)
302-306 F5.3 --- e_HR1M1 ?=- Error on MOS1 HR1
308-313 F6.3 --- HR2M1 ?=- HR2 for EPIC-MOS1 (5)
316-320 F5.3 --- e_HR2M1 ?=- Error on MOS1 HR2
322-327 F6.3 --- HR3M1 ?=- HR3 for EPIC-MOS1 (5)
330-334 F5.3 --- e_HR3M1 ?=- Error on MOS1 HR3
336-341 F6.3 --- HR4M1 ?=- HR4 for EPIC-MOS1 (5)
343-348 F6.3 --- e_HR4M1 ?=- Error on MOS1 HR4
350-355 F6.3 --- HR1M2 ?=- HR1 for EPIC-MOS2 (5)
358-362 F5.3 --- e_HR1M2 ?=- Error on MOS2 HR1
364-369 F6.3 --- HR2M2 ?=- HR2 for EPIC-MOS2 (5)
372-376 F5.3 --- e_HR2M2 ?=- Error on MOS2 HR2
378-383 F6.3 --- HR3M2 ?=- HR3 for EPIC-MOS2 (5)
386-390 F5.3 --- e_HR3M2 ?=- Error on MOS2 HR3
392-397 F6.3 --- HR4M2 ?=- HR4 for EPIC-MOS2 (5)
399-406 F8.3 --- e_HR4M2 ?=- Error on MOS2 HR4
410-417 E8.2 --- Lik Total detection likelihood
419 I1 --- Qual Overall quality flag (6)
422 I1 --- STV Short-term variability flags (7)
424 I1 --- LTV Long-term variability flags (7)
428-429 I2 --- Num Number of individual detections
431-438 E8.2 mW/m2 FX ?=- Unabsorbed X-ray flux in 0.5-10.keV
440-444 F5.2 [-] Lx/L ?=- Luminosity ratio, log(LX/Lbol)
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Note (1): Code as follows:
1 = O stars with S=0 (good X-ray quality) (35 objects)
2 = B stars with S=0 (good X-ray quality) (91 objects)
3 = WR stars with S=0 (good X-ray quality) (7 objects)
4 = O stars with S!=0 (potentially spurious X-ray source) (98 objects)
5 = B stars with S!=0 (potentially spurious X-ray source) (70 objects)
6 = WR stars with S!=0 (potentially spurious X-ray source) (9 objects)
Note (2): A letter is indicated if the star belongs to a pair, i.e., this
star and another one sharing the same character (a, b, c, d, or e)
correspond to the same X-ray source.
Note (3): It begins with ∼ if taken from Simbad
Note (4): B.C. Reed remarked that the identification of ALS 1855 to ALS
15858 in Simbad was wrong, they are actually two stars. This would
mean that the total bolometric flux, in logarithmic scale, for these
two objects would be -6.81, leading to a decrease of the
log(LX/LBOL) ratio by 0.23dex (i.e. log(LX/LBOL)=-6.47). This
doesn't change the conclusions presented in the paper.
Note (5): Hardness ratios are defined as HR=(H-S)/(H+S), where
HR1 = S=0.2-0.5keV and H=0.5-1.0keV
HR2 = S=0.5-1.0keV and H=1.0-2.0keV
HR3 = S=1.0-2.0keV and H=2.0-4.5keV
HR4 = S=2.0-4.5keV and H=4.5-12.0keV
Note (6): Quality flag is set to be zero if the X-ray source has no problem
and to 1-4 if possibly spurious
Note (7): Short-term flag is set to be 1 if the source was found to be
variable with a significance level of 0.001% following a chi2 test
performed on the time series of the individual exposures, and
otherwise 0. Long-term variability, between exposures, was also
investigated. The long-term flag is set to be 2 if there are not
enough exposures (0 or 1 observation for all combinations of
filters/instruments), to 1 if a chi2 test detected variations in the
count rate with a significance level of 1%, and otherwise to 0.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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2- 6 I5 --- ALS ID Number in Reed catalog
10- 34 A25 --- Name Usual name of the source
36- 43 E8.2 cm-2 N(H,int) ?=- Interstellar absorption column
46- 49 F4.2 --- chi2 Chi-square of the fit
51- 54 I4 --- dof Number of degrees of freedom
56- 63 E8.2 mW/m2 Ft Observed flux in 0.5-10keV
65- 72 E8.2 mW/m2 Fs Observed flux in 0.5-1keV
74- 81 E8.2 mW/m2 Fm Observed flux in 1.-2.5keV
83- 90 E8.2 mW/m2 Fh Observed flux in 2.5-10keV
92- 99 E8.2 mW/m2 unFt Unabsorbed flux in 0.5-10keV
101-108 E8.2 mW/m2 unFs Unabsorbed flux in 0.5-1keV
110-117 E8.2 mW/m2 unFm Unabsorbed flux in 1.-2.5keV
119-126 E8.2 mW/m2 unFh Unabsorbed flux in 2.5-10keV
128-131 F4.2 10+22cm-2 N(H) Fitted absorption column
133-136 F4.2 10+22cm-2 N(H)l ?=- Lower limit of the 90% conf. int. on N(H)
138-141 F4.2 10+22cm-2 N(H)u ?=- Upper limit of the 90% conf. int. on N(H)
143-147 F5.2 keV kT1 ?=- Temperature of the first mekal component
149-153 F5.2 keV kT1l ?=- Lower limit of the 90% conf. int. on kT1
155-159 F5.2 keV kT1u ?=- Upper limit of the 90% conf. int. on kT1
161-167 E7.2 cm-5 norm1 Normalization factor of kT1
169-175 E7.2 cm-5 norm1l ?=- Lower limit of the 90% conf. int. on norm1
177-183 E7.2 cm-5 norm1u ?=- Upper limit of the 90% conf. int. on norm1
185-189 F5.2 keV kT2 ? Temperature of the second mekal component
191-195 F5.2 keV kT2l ? Lower limit of the 90% conf. int. on kT2
197-201 F5.2 keV kT2u ? Upper limit of the 90% conf. int. on kT2
203-209 E7.2 cm-5 norm2 ? Normalization factor of kT2
211-217 E7.2 cm-5 norm2l ? Lower limit of the 90% conf. int. on norm2
219-225 E7.2 cm-5 norm2u ? Upper limit of the 90% conf. int. on norm2
227-231 F5.2 keV kT3 ? Temperature of the third mekal component
233-237 F5.2 keV kT3l ? Lower limit of the 90% conf. int. on kT3
239-243 F5.2 keV kT3u ? Upper limit of the 90% conf. int. on kT3
245-251 E7.2 cm-5 norm3 ? Normalization factor of kT3
253-259 E7.2 cm-5 norm3l ? Lower limit of the 90% conf. int. on norm3
261-267 E7.2 cm-5 norm3u ? Upper limit of the 90% conf. int. on norm3
269-332 A64 --- Remarks Additional remarks
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Acknowledgements:
Yael Naze, ynaze(at )uliege.be
References:
Naze & Mocth, Paper II 2018A&A...619A.148N 2018A&A...619A.148N, Cat. J/A+A/619/A148
(End) Yael Naze [ULg, Belgium], Patricia Vannier [CDS] 10-Aug-2009