J/MNRAS/419/2095 HMXBs in nearby galaxies (Mineo+, 2012)
X-ray emission from star-forming galaxies. I. High-mass X-ray binaries.
Mineo S., Gilfanov M., Sunyaev R.
<Mon. Not. R. Astron. Soc. 419, 2095 (2012)>
=2012MNRAS.419.2095M 2012MNRAS.419.2095M
ADC_Keywords: Binaries, X-ray ; Galaxies, nearby
Keywords: X-rays: binaries ; X-rays: galaxies ; galaxies: starburst ;
galaxies: spirals; galaxies: irregulars ; stars: formation
Abstract:
Based on a homogeneous set of X-ray, infrared and ultraviolet
observations from Chandra, Spitzer, GALEX and 2MASS archives, we study
populations of high-mass X-ray binaries (HMXBs) in a sample of 29
nearby star-forming galaxies and their relation with the star
formation rate (SFR). In agreement with previous results, we find that
HMXBs are a good tracer of the recent star formation activity in the
host galaxy and their collective luminosity and number scale with the
SFR, in particular, LX≈2.6x1039SFR. However, the scaling relations
still bear a rather large dispersion of rms∼0.4dex, which we believe
is of a physical origin.
We present the catalog of 1057 X-ray sources detected within the D25
ellipse for galaxies of our sample and construct the average X-ray
luminosity function (XLF) of HMXBs with substantially improved
statistical accuracy and better control of systematic effects than
achieved in previous studies. The XLF follows a power law with slope
of 1.6 in the log(LX)∼35-40 luminosity range with a moderately
significant evidence for a break or cut-off at LX∼1040erg/s. As
before, we did not find any features at the Eddington limit for a
neutron star or a stellar mass black hole.
We discuss implications of our results for the theory of binary
evolution. In particular we estimate the fraction of compact objects
that once upon their lifetime experienced an X-ray active phase
powered by accretion from a high mass companion and obtain a rather
large number, fX∼0.2x(0.1Myr/τx) (τx is the life time of the
X-ray active phase). This is about 4 orders of magnitude more frequent
than in LMXBs. We also derive constrains on the mass distribution of
the secondary star in HMXBs.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sfgal.dat 86 29 Sample of nearby star-forming galaxies
resolved by Chandra
hmxb.dat 88 1055 High-mass X-ray binaries Catalogue
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See also:
B/cb : Cataclysmic Binaries, LMXBs, and related objects (Ritter+, 2011)
Byte-by-byte Description of file: sfgal.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 7 A7 --- Galaxy Galaxy name (default catalog is NGC)
9- 10 I2 --- ID [1/29]+ Sequential number of galaxy
12- 16 F5.1 Mpc d Distance
18- 19 I2 --- r_d Reference for distance (1)
21- 32 A12 --- MType Hubble type (2)
34- 35 I2 deg i ?=- Inclination angle (3)
37- 39 F3.1 arcmin Rx Radius of the elliptical region used for
the analysis (4)
41- 46 F6.3 Msun/yr SFR Star formation rate Spitzer and GALEX data (5)
48- 53 F6.4 Msun M* Stellar mass from 2MASS data (5)
55- 59 F5.2 10-10/yr SFR/M* Specific star formation rate (6)
61- 65 F5.2 [10-7W] logLlim logarithm of the sensitivity limit
in 0.5-8keV band (7)
67- 68 I2 --- Nxrb Number of detected XRBs (8)
70- 74 F5.2 [10-7W] logLxrb logarithm of the collective X-ray luminosity
of XRBs in the 0.5-8keV band (9)
76- 80 F5.2 --- Ncxb Predicted number of cosmic X-ray background
sources (10)
82- 86 F5.2 [10-7W] logLcxb logarithm of the predicted X-ray luminosity
of the CXB sources
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Note (1): References for distances as follows:
1 = Sanders et al. (2003AJ....126.1607S 2003AJ....126.1607S)
2 = Tully (1988Sci...242..310T 1988Sci...242..310T)
3 = Grise et al. (2008A&A...486..151G 2008A&A...486..151G)
4 = Georgiev et al. (2006A&A...452..141G 2006A&A...452..141G)
5 = Makarova & Karachentsev (2003Ap.....46..144M 2003Ap.....46..144M)
6 = Willick et al. (1997ApJS..109..333W 1997ApJS..109..333W)
7 = Saha et al. (2006ApJS..165..108S 2006ApJS..165..108S)
8 = Sakai & Madore (1999ApJ...526..599S 1999ApJ...526..599S)
9 = Ismail et al. (2005JKoAS..38....7I 2005JKoAS..38....7I)
10 = Saviane, Hibbard, & Rich (2004AJ....127..660S 2004AJ....127..660S)
11 = Drozdovsky et al. (2002AJ....124..811D 2002AJ....124..811D)
12 = Seth, Dalcanton, & de Jong (2005AJ....129.1331S 2005AJ....129.1331S)
13 = Takats & Vinko (2006MNRAS.372.1735T 2006MNRAS.372.1735T)
14 = Sakai et al. (2004ApJ...608...42S 2004ApJ...608...42S)
15 = Drozdovsky & Karachentsev (2000A&AS..142..425D 2000A&AS..142..425D)
16 = Tully et al. (2009AJ....138..323T 2009AJ....138..323T)
17 = Wolter & Trinchieri (2004A&A...426..787W 2004A&A...426..787W)
Note (2): Hubble type from de Vaucouleurs, de Vaucouleurs, & Corwin,
1976RC2...C......0D 1976RC2...C......0D (Cat. VII/112)
Note (3): Inclination angles from Tully (1988Sci...242..310T 1988Sci...242..310T).
Note (4): Radius of the galactic region where the HMXBs dominate the
compact X-ray source population, defined by mean of spatial analysis
performed on individual galaxies (see Sect.4.3 of the reference paper
for description). For The Antennae we have analyzed a region that
includes the two galaxies in the merging system (NGC4038 and NGC4039).
It is centered at RA=180.472-18.881°(J2000) and has axis ratio=1.4
and PA=78°.
Note (5): Estimated inside the galactic regions (Sect.4.3 of the reference
paper).
Note (6): Star formation rate-to-stellar mass ratio.
Note (7): The sensitivity limit is defined as the luminosity level
corresponding to a value of the incompleteness function K(L)=0.6.
Note (8): Number of X-Ray Binaries with luminosity above the sensitivity
limit, detected within the galactic region where the HMXBs (high-mass
XRB) dominate the compact X-ray source population. It corresponds to
the total number of detected point sources corrected for the
predicted contribution of CXB sources in the same area.
Note (9): Base-10 logarithm of the total X-ray luminosity of galaxies in
the 0.5-8keV band, estimated by using eq. (21).
Note (10): Predicted number of Cosmic X-ray background (CXB) sources within
the selected region, with luminosity above the sensitivity limit.
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Byte-by-byte Description of file: hmxb.dat
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Bytes Format Units Label Explanations
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1- 7 A7 --- Galaxy Galaxy name (default catalog is NGC)
9- 11 I3 --- Seq Sequential number of X-ray source in Galaxy
13- 16 A4 --- CXO Chandra X-ray Observatory (CXO) designation (1)
18- 33 A16 --- CXOJ Chandra X-ray Observatory (CXO) source
name (JHHMMSS.s-DDMMSS)
35- 43 F9.5 deg RAdeg Right ascension (J2000)
45- 53 F9.5 deg DEdeg Declination (J2000)
55- 59 F5.1 arcsec d Distance from the galaxy center
61- 67 F7.1 ct S Number of source counts after background
subtraction
69- 73 F5.1 ct e_S rms uncertainty on S
75- 80 F6.2 [mW/m2] logFx logarithm of the X-ray flux, 0.5-8keV
82- 86 F5.2 [10-7W] logLx logarithm of the X-ray luminosity, 0.5-8keV
88 I1 --- loc [1/3] location flag (2)
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Note (1): CXO designation, according to the CHANDRA-discovered source
naming convention: CXOU is used for "unregistered" sources found, CXO
is used for sources matched with the The Chandra Source Catalog (CSC).
Note (2): Location flag as follows:
1 = point sources detected in the galactic area dominated by
high-mass X-ray binary (HMXB) population
2 = point sources detected in the outer region dominated by CXB sources
3 = point sources detected in the bulge and assumed to be
low-mass X-ray binaries (LMXBs)
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Acknowledgements:
Stefano Mineo, mineo(at)MPA-Garching.MPG.DE (MPA-Garching)
(End) Stefano Mineo [MPA-Garching], Francois Ochsenbein [CDS] 26-Sep-2011