J/ApJ/907/17 HMXB-dominant galaxy sample and properties (Lehmer+, 2021)
The Metallicity Dependence of the High-mass X-Ray Binary Luminosity Function.
Lehmer B.D., Eufrasio R.T., Basu-Zych A., Doore K., Fragos T., Garofali K.,
Kovlakas K., Williams B.F., Zezas A., Santana-Silva L.
<Astrophys. J., 907, 17 (2021)>
=2021ApJ...907...17L 2021ApJ...907...17L
ADC_Keywords: Binaries, X-ray; Galaxies; X-ray sources; Star Forming Region;
Abundances, [Fe/H]
Keywords: High-mass x-ray binary stars ; Metallicity ; Star formation ;
Spiral galaxies ; X-ray binary stars ; X-ray astronomy ;
Compact objects
Abstract:
In this work, we present detailed constraints on the metallicity
dependence of the high-mass X-ray binary (HMXB) X-ray luminosity
function (XLF). We analyze ∼5Ms of Chandra data for 55 actively
star-forming galaxies at D≤30Mpc, with gas-phase metallicities
spanning 12+log(O/H)∼7-9.2. Within the galactic footprints, our sample
contains a total of 1311 X-ray point sources, of which ∼49% are
expected to be HMXBs, with the remaining sources likely to be low-mass
X-ray binaries (LMXBs; ∼22%) and unrelated background sources (∼29%).
We construct a model that successfully characterizes the average HMXB
XLF over the full metallicity range. We demonstrate that the SFR-
normalized HMXB XLF shows clear trends with metallicity, showing
steadily increasing numbers of luminous and ultraluminous X-ray
sources (logL(erg/s)=38-40.5) with declining metallicity. However, we
find that the low-luminosity (logL(erg/s)=36-38) HMXB XLF appears to
show a nearly constant SFR scaling and slope with metallicity. Our
model provides a revised scaling relation of integrated LX/SFR versus
12+log(O/H), and a new characterization of its SFR-dependent
stochastic scatter. The general trend of this relation is broadly
consistent with past studies based on integrated galaxy emission;
however, our model suggests that this relation is driven primarily by
the high-luminosity end of the HMXB XLF. Our results have implications
for binary population synthesis models, the nature of super-Eddington
accreting objects (e.g., ultraluminous X-ray sources), recent efforts
to identify active galactic nucleus candidates in dwarf galaxies, and
the X-ray radiation fields in the early universe during the epoch of
cosmic heating at z≥10.
Description:
We made use of the NASA/IPAC Extragalactic Database (NED), which is
operated by the Jet Propulsion Laboratory, California Institute of
Technology, under contract with NASA. Our work includes observations
made via the NASA Galaxy Evolution Explorer (GALEX). GALEX is operated
for NASA by the California Institute of Technology under NASA contract
NAS5-98034. This publication makes use of data products from the Two
Micron All Sky Survey (2MASS), which is a joint project of the
University of Massachusetts and the Infrared Processing and Analysis
Center/California Institute of Technology, funded by NASA and the
National Science Foundation (NSF). This work is based on observations
made with the Spitzer Space Telescope, obtained from the NASA/IPAC
Infrared Science Archive, both of which are operated by the Jet
Propulsion Laboratory, California Institute of Technology, under a
contract with NASA. We acknowledge the use of public data from the
Swift data archive.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 111 55 HMXB-dominant galaxy sample and properties
tablea1.dat 101 2531 X-ray point-source catalog and properties
refs.dat 53 20 References used
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See also:
J/ApJ/602/231 : Chandra X-ray point sources in nearby galaxies (Colbert+, 2004)
J/ApJ/617/240 : Oxygen abundances in the GOODS-North field (Kobulnicky+, 2004)
J/A+A/464/885 : Abundances in 53 HII regions (Guseva+, 2007)
J/ApJS/169/401 : ChaMP X-ray point source catalog (Kim+, 2007)
J/ApJ/681/1163 : Late-type galaxies in Chandra deep fields (Lehmer+, 2008)
J/ApJ/695/580 : Oxygen abundance in M83 (Bresolin+, 2009)
J/ApJS/190/233 : Spectroscopy & abundances of SINGS galaxies (Moustakas+, 2010)
J/ApJ/741/49 : ULX candidates in nearby galaxies (Swartz+, 2011)
J/ApJS/193/31 : M33 Chandra ACIS survey: final catalog (Tullmann+, 2011)
J/MNRAS/416/1844 : 2XMM ultraluminous X-ray source candidates (Walton+, 2011)
J/A+A/546/A122 : SDSS metal-poor emission-line galaxies (Izotov+, 2012)
J/MNRAS/419/2095 : HMXBs in nearby galaxies (Mineo+, 2012)
J/ApJ/764/41 : X-ray binary evolution across cosmic time (Fragos+, 2013)
J/ApJ/776/L31 : Energy feedback from XRB from z=0 to z=19.92 (Fragos+, 2013)
J/AJ/146/86 : Cosmicflows-2 catalog (Tully+, 2013)
J/ApJ/774/136 : X-ray obs. of SINGS gal. compared to models (Tzanavaris+, 2013)
J/ApJS/218/9 : Deep XMM-Newton survey of M33 (Williams+, 2015)
J/ApJ/825/7 : Evolution of ∼6Ms CDF-S galaxies (Lehmer+, 2016)
J/ApJ/829/20 : Chandra ACIS survey in nearby galaxies. II (Wang+, 2016)
J/ApJ/887/20 : Deep Chandra survey of the SMC. III. HMXBs (Antoniou+, 2019)
J/MNRAS/483/5554 : Non-nuclear X-ray sources nearby galaxies (Earnshaw+, 2019)
J/ApJS/243/3 : Chandra observations of SINGS galaxies (Lehmer+, 2019)
J/ApJ/890/150 : X-ray binaries in M101 with HST optical data (Chandar+, 2020)
J/ApJS/248/31 : HST & Chandra obs. of elliptical galaxies (Lehmer+, 2020)
http://leda.univ-lyon1.fr/ : Hyperleda online base
Byte-by-byte Description of file: table1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- GalID Adopted galaxy designation (with Messier
designation)
21- 22 I2 h RAh [0/23] Hour of Right Ascension, central position
(J2000)
24- 25 I2 min RAm Minute of Right Ascension, central position
(J2000)
27- 30 F4.1 s RAs Second of Right Ascension, central position
(J2000)
32- 32 A1 --- DE- [±] Sign of the Declination, central position
(J2000)
33- 34 I2 deg DEd Degree of Declination, central position (J2000)
36- 37 I2 arcmin DEm Arcminute of Declination, central position
(J2000)
39- 42 F4.1 arcsec DEs Arcsecond of Declination, central position
(J2000)
44- 48 F5.2 Mpc Dist [1.9/29.4] Adopted distance
50- 53 F4.2 Mpc e_Dist [0.03/7]? 1σ uncertainty in Dist
55- 58 F4.2 arcmin a [0.1/6.59] Isophotal ellipse parameter,
semi-major axis (1)
60- 63 F4.2 arcmin b [0.05/4.01] Isophotal ellipse parameter,
semi-minor axis (1)
65- 69 F5.1 deg PA [10/180] Isophotal ellipse parameter, Position
angle, east of north (1)
71- 75 F5.2 [Msun] Mass [7.29/10.5]? Log of the galactic stellar mass
77- 82 F6.4 Msun/yr SFR [0.0007/8.97] Star-formation rate within the
defined region
84- 87 F4.2 [-] [O/H] [7.17/9.1] Adopted estimate of the average
oxygen abundance, 12+log(O/H) (2)
89- 92 F4.2 [-] e_[O/H] [0.0/0.23] Uncertainty in [O/H] (2)
94- 96 I3 ks Texp [4/853] Cumulative Chandra exposure time
98-101 F4.1 [10-7W] [L50] [35.5/38.5] log, 0.5-8keV luminosity, erg/s
103-105 I3 --- Nx [0/363] Number of X-ray detected sources within
the galactic footprints (3)
107-108 I2 --- r_Dist [1/12] Reference for Dist
110-111 I2 --- r_[O/H] [1/20] Reference for [O/H]
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Note (1): The majority of the main-sample galaxies have size
parameters based on 2MASS Ks-band data from Jarrett+,
2003AJ....125..525J 2003AJ....125..525J. In these cases, the Ks-band 20mag/arcsec2
ellipses were used to avoid large contamination from background
sources; however, for galaxies with Ks-band 20 mag/arcsec2
semi-major axes a <1arcmin, we chose to adopt the "total" Ks-band
ellipses. For the main-sample galaxies DDO68, NGC4861, and IC2574, and
all galaxies in the supplemental sample, we adopted the positions and
D25 sizes using the HyperLeda database (http://leda.univ-lyon1.fr/).
Note (2): Adopted estimate of the average oxygen abundances, 12+log(O/H).
For consistency with other studies of XRB scaling relations that include
metallicity, we have converted all abundances to the Pettini & Pagel
(2004MNRAS.348L..59P 2004MNRAS.348L..59P; PP04) calibration following the prescriptions in
Kewley & Ellison (2008ApJ...681.1183K 2008ApJ...681.1183K).
Note (3): Number of X-ray detected sources within the galactic footprints
defined by RA, DE, a, b, PA parameters.
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Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 19 A19 --- GalID Name of the host galaxy
21- 23 I3 --- Name [1/456] Point-source identification number
within the galaxy
25- 34 F10.6 deg RAdeg [2.43/360] Right Ascension, point source,
decimal degrees (J2000)
36- 45 F10.6 deg DEdeg [-76.7/68.6] Declination, point source,
decimal degrees (J2000)
47- 50 F4.1 arcmin theta [0/12.4] Angular offset, point source
relative to average aim point of Chandra
observation
52- 59 F8.1 --- NFB [0.8/114995] 0.5-7keV net counts
61- 65 F5.1 --- e_NFB [1/359] Uncertainty in NFB
67- 71 F5.3 10+22cm-2 NH [0.006/9.8] Best-fit H column density (1)
73- 77 F5.3 10+22cm-2 e_NH [0.006/7.7] Uncertainty in NH (1)
79- 82 F4.2 --- Gamma [0.09/3.3] Best-fit photon index (1)
84- 88 F5.2 --- e_Gamma [-10/2.19]?=1.7 Uncertainty in Gamma (1)
90- 94 F5.1 [mW/m2] logFFB [-16.6/-11.7] log, 0.5-8 keV flux, erg/s/cm2
96- 99 F4.1 [10-7W] logLFB [34.4/40.5] log, 0.5-8 keV luminosity, erg/s
101-101 I1 --- Flag [1/5] Location Flag (2)
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Note (1): Best-fit column density NH and photon index Γ,
respectively, along with their respective 1σ errors, based on
spectral fits to an absorbed power-law model (TBABSGal*TBABS*POW in
xspec). For sources with small numbers of counts (<20 net counts), we
adopted only Galactic absorption appropriate for each galaxy and a
photon index of Γ=1.7. In these cases the Γ uncertainty is
set equal to 1.7. When the uncertainty for Γ is equal to -1, the
values of Γ are upper limits.
Note (2): Flag as follows:
1 = the source has L>10+35Lsun, is within the galactic footprint
adopted in Table1, and is outside a central region of avoidance,
if applicable. All XLF calculations are based on Flag=1 sources
2 = the source is within the adopted galactic footprint, but has a
luminosity of L<10+35Lsun, and was thus excluded from our
XLF analysis
3 = the source is outside the adopted galactic footprint, but within
20% of its outer boundary. These sources are candidates for
belonging to the galaxies, but have a high chance of being
background objects
4 = the source is located in the central region of avoidance due to
either the presence of an AGN or very high levels of source confusion
5 = the source is >1.2times the angular distance to the adopted
galactic boundary.
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Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 3 I3 --- Ref [1/20] Reference code
5- 18 A14 --- Autor Main autor
20- 38 A19 --- BIB BIBcode
40- 53 A14 --- Cat. Catalog in Vizier
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History:
From electronic version of the journal
(End) Prepared by [AAS], Coralie Fix [CDS], 30-May-2022