J/ApJ/817/95 X-ray observations of HCG galaxies (Tzanavaris+, 2016)
Exploring X-ray binary populations in compact group galaxies with Chandra.
Tzanavaris P., Hornschemeier A.E., Gallagher S.C., Lenkic L.,
Desjardins T.D., Walker L.M., Johnson K.E., Mulchaey J.S.
<Astrophys. J., 817, 95 (2016)>
=2016ApJ...817...95T 2016ApJ...817...95T (SIMBAD/NED BibCode)
ADC_Keywords: Galaxy catalogs ; X-ray sources ; Morphology ; Binaries, X-ray
Keywords: X-rays: binaries; X-rays: galaxies
Abstract:
We obtain total galaxy X-ray luminosities, LX, originating from
individually detected point sources in a sample of 47 galaxies in 15
compact groups of galaxies (CGs). For the great majority of our
galaxies, we find that the detected point sources most likely are
local to their associated galaxy, and are thus extragalactic X-ray
binaries (XRBs) or nuclear active galactic nuclei (AGNs). For spiral
and irregular galaxies, we find that, after accounting for AGNs and
nuclear sources, most CG galaxies are either within the ±1σ
scatter of the Mineo et al. LX-star formation rate (SFR) correlation
or have higher LX than predicted by this correlation for their SFR.
We discuss how these "excesses" may be due to low metallicities and
high interaction levels. For elliptical and S0 galaxies, after
accounting for AGNs and nuclear sources, most CG galaxies are
consistent with the Boroson et al. LX-stellar mass correlation for
low-mass XRBs, with larger scatter, likely due to residual effects
such as AGN activity or hot gas. Assuming non-nuclear sources are low-
or high-mass XRBs, we use appropriate XRB luminosity functions to
estimate the probability that stochastic effects can lead to such
extreme LX values. We find that, although stochastic effects do not
in general appear to be important, for some galaxies there is a
significant probability that high LX values can be observed due to
strong XRB variability.
Description:
In this paper we study a sample of 15 compact groups (CGs) observed
with Chandra/ACIS, Swift/UVOT and Spitzer/IRAC-MIPS for which archival
data exist, allowing us to obtain SFRs, stellar masses, sSFRs and
X-ray fluxes and luminosities. Table 1 shows the group sample,
including redshifts, luminosity distances and group evolutionary
types. Allowing for the fact that some galaxies do not fall in the
field of view of all three instruments, the total number of CG
galaxies analyzed is 47.
Details on the Swift and Spitzer observations and data for systems in
this sample can be found in Tzanavaris et al. (2010ApJ...716..556T 2010ApJ...716..556T)
and (L. Lenkic et al. 2015, in preparation). For Chandra/ACIS
observations we refer the reader to Tzanavaris et al. (2014,
J/ApJS/212/9) and Desjardins et al. (2013ApJ...763..121D 2013ApJ...763..121D;
2014ApJ...790..132D 2014ApJ...790..132D).
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
table1.dat 55 15 Compact group sample
table3.dat 85 47 Compact group (CG) galaxy results
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See also:
B/chandra : The Chandra Archive Log (CXC, 1999-2014)
VII/213 : Hickson's Compact groups of Galaxies (Hickson+ 1982-1994)
J/ApJS/212/9 : X-ray sources in Hickson Compact Groups (Tzanavaris+, 2014)
J/A+A/565/A25 : Hickson compact groups Herschel observations (Bitsakis+, 2014)
J/ApJ/779/102 : Metallicities of RGB stars in dwarf galaxies (Kirby+, 2013)
J/ApJ/766/19 : XRB population synthesis models in 0<z<20 gal (Tremmel+, 2013)
J/ApJ/764/41 : X-ray binary evolution across cosmic time (Fragos+, 2013)
J/ApJ/749/130 : X-ray binaries in NGC 1291 with Chandra (Luo+, 2012)
J/MNRAS/419/2095 : HMXBs in nearby galaxies (Mineo+, 2012)
J/ApJS/195/10 : The CDF-S survey: 4Ms source catalogs (Xue+, 2011)
J/ApJ/721/98 : Morphology of 70um COSMOS galaxies (Kartaltepe+, 2010)
J/AJ/139/279 : Outlying HII regions in HI-selected galaxies (Werk+, 2010)
J/A+A/497/635 : XMM-Newton wide-field survey in COSMOS (Cappelluti+, 2009)
J/ApJ/692/556 : Star forming galaxy templates (Rieke+, 2009)
J/AJ/136/2782 : Star formation efficiency in nearby galaxies (Leroy+, 2008)
J/ApJ/681/1163 : Late-type galaxies in Chandra deep fields (Lehmer+, 2008)
J/AJ/130/55 : Modelled Lick indices for galaxies (Mendes+, 2005)
J/AJ/127/1811 : Catalog of SDSS compact groups of galaxies (Lee+, 2004)
J/ApJS/150/19 : ChaMP. I. First X-ray source catalog (Kim+, 2004)
J/ApJS/143/315 : IRAS 1Jy sample of ultraluminous gal. II. (Veilleux+, 2002)
J/AJ/124/2351 : Chandra Deep Field North survey. XII (Bauer+, 2002)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1 A1 --- Cat Catalog identifier (G1)
3- 5 I3 --- HCG Compact group number (HCG or RSCG for #17)
7- 12 F6.4 --- z [0.008/0.03] Redshift
14- 17 I4 km/s Vel [2364/7026] Velocity from NED (1)
19- 23 F5.1 Mpc Dist [34/102] NED Luminosity Distance (DL)
25- 27 A3 --- Type Group evolutionary HI type (2)
29- 43 A15 --- ObsID Chandra X-ray observations ID(s)
45 A1 --- Inst Chandra-ACIS array
47- 51 F5.1 ks Exp [12.7/169.2] Exposure time
53- 55 A3 --- Ref Reference of the X-ray data (3)
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Note (1): Velocity from NASA Extragalactic Database (NED) relative to the
cosmic microwave background velocity
(Fixsen et al. 1996ApJ...473..576F 1996ApJ...473..576F).
Note (2): Group evolutionary HI type as measured and defined by
Johnson et al. (2007AJ....134.1522J 2007AJ....134.1522J) and as follows:
I = HI rich (logMHI/logMdyn>0.9);
II = intermediate (logMHI/logMdyn=0.8-0.9); and
III = HI poor (logMHI/logMdyn<0.8);
Note (3): For further details and references on the X-ray data see
these following papers:
D14 = Desjardins et al. 2014ApJ...790..132D 2014ApJ...790..132D
T14 = Tzanavaris et al. 2014, J/ApJS/212/9
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 A1 --- Cat Catalog identifier (G1)
3- 5 I3 --- HCG Compact group number (HCG or RSCG for #17)
6- 8 A3 --- Gal Galaxy component(s)
10- 11 A2 --- TT Morphological Hubble type based on
best-fitting SED template
13- 17 F5.2 Msun/yr SFR [0.02/16.8] Star Formation Rate
19- 22 F4.2 Msun/yr e_SFR [0/2.3] Uncertainty in SFR
24- 28 F5.2 10+10Msun M* [0.2/32.5] Stellar Mass, 1010 solar mass
30- 33 F4.2 10+10Msun e_M* [0.02/0.5] Uncertainty in M*, 1010 solar mass
35- 40 F6.2 10+33W LX [0.05/213] Total X-ray point source luminosity
in the 0.5-8.0keV Chandra band, 1040erg/s
42- 46 F5.2 10+33W E_LX [0.02/4.1] Upper error on LX
48- 52 F5.2 10+33W e_LX [0.02/3.1] Lower error on LX
54- 55 I2 --- Nx [1/14] Number of detected point sources
57- 60 F4.2 --- fLx [0.02/1]?=0 Fraction of the total luminosity
contributed by a central source
62- 65 F4.1 10-18W/m2 Flim [0.5/41.2] Flux limit, 10-15erg/cm^2/s
67- 71 F5.1 10+31W LXlim [1.2/326] 0.5-8.0keV luminosity limit,
1038erg/s
73- 75 F3.1 --- PCG [0.5/1] Probability that a source detected
within the galaxy boundaries belongs to
the CG galaxy
77- 80 F4.2 --- PBa [0/0.3] Probability of measuring a total galaxy
luminosity greater than or equal to the
observed value
82- 85 F4.2 --- PBb [0/0.7] Same as PBa, assuming a two order of
magnitude range in luminosity for
variable individual point sources
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Global notes:
Note (G1): Catalog as follows:
H = HCG: Hickson et al. 1992, VII/213
R = RSCG: Redshift Survey Compact Groups, Barton et al. 1996AJ....112..871B 1996AJ....112..871B
This RSCG is part of a larger sample selected by
Walker et al. (2012AJ....143...69W 2012AJ....143...69W) to have properties similar to
those of HCGs.
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Acknowledgments:
Tzanavaris, Panayiotis [UNIVERSITY OF MARYLAND BALTIMORE COUNTY] for
providing coordinates of table 3.
Please note, these are not necessarily strict coordinates of the galaxy
nucleus. They are coordinates of the first X-ray point source within the
galaxy. However, for the purposes of galaxy identification, this should be
adequate.
History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 07-Apr-2016