J/AJ/158/169 The hot gas exhaust of starburst engines in mergers (Smith+, 2019)
The hot gas exhaust of starburst engines in mergers: testing models of stellar
feedback and star formation regulation.
Smith B.J., Wagstaff P., Struck C., Soria R., Dunn B., Swartz D.,
Giroux M.L.
<Astron. J., 158, 169-169 (2019)>
=2019AJ....158..169S 2019AJ....158..169S (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; X-ray sources ; Interstellar medium
Keywords: galaxies: interactions - galaxies: ISM - X-rays: galaxies
Abstract:
Using archival data from the Chandra X-ray telescope, we have measured
the spatial extent of the hot interstellar gas in a sample of 49 nearby
interacting galaxy pairs, mergers, and merger remnants. For systems with
SFR>1 M☉/yr, the volume and mass of hot gas are strongly and
linearly correlated with the star formation rate (SFR). This supports
the idea that stellar/supernovae feedback dominates the production of
hot gas in these galaxies. We compared the mass of X-ray-emitting hot gas
MX(gas) with the molecular and atomic hydrogen interstellar gas masses
in these galaxies (MH2 and MHI, respectively), using published carbon
monoxide and 21 cm H I measurements. Systems with higher SFRs have larger
MX(gas)/(MH2 + MHI) ratios on average, in agreement with recent
numerical simulations of star formation and feedback in merging galaxies.
The MX(gas)/(MH2 + MHI) ratio also increases with dust temperature
on average. The ratio MX(gas)/SFR is anticorrelated with the Infrared
Astronomical Satellite 60-100 µm flux ratio and with the Spitzer
3.6-24 µm color. These trends may be due to variations in the spatial
density of young stars, the stellar age, the ratio of young to old stars,
the initial mass function, and/or the efficiency of stellar feedback.
Galaxies with low SFR (<1 M☉/yr) and high K band luminosities may
have an excess of hot gas relative to the relation for higher SFR galaxies,
while galaxies with low K band luminosities (and therefore low stellar
masses) may have a deficiency in hot gas, but our sample is not large
enough for strong statistical significance.
Description:
Briefly, the sample includes 49 premerger interacting pairs, postmerger
remnants, and midmerger systems in the nearby universe (distance <180 Mpc).
Initially, galaxies were chosen based on their morphologies from the Arp
(1966apg..book.....A 1966apg..book.....A) Atlas of Peculiar Galaxies, or from other published
surveys of mergers and merger remnants, selecting approximately equal-mass
interacting pairs or the remnants of the merger of such pairs. The final
sample was then selected based on the availability of suitable Chandra
data. See Smith et al. (2018, J/AJ/155/81, Paper I) for details.
All of the sample galaxies were observed with the Chandra ACIS-S array,
and all of the galaxies fit well within the 8.3'x8.3' field of view of
the S3 chip of this array. Details of the individual observations,
including exposure times and ObsID numbers, are provided in Paper I.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 61 49 Basic data on sample galaxies
table2.dat 69 49 Global molecular and atomic gas mass in
the sample galaxies
table3.dat 110 50 Final ellipses used for volume calculations
at 0.3-1.0 keV surface brightness of
3x10-9 photons/s/cm2/arcsec2
table4.dat 110 27 Outer (2σ) ellipses for galaxies with
high-S/N observations
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See also:
IX/57 : The Chandra Source Catalog (CSC), Release 2.0 (Evans+, 2019)
J/MNRAS/361/34 : HIPASS catalogue. III. (Doyle+, 2005)
J/MNRAS/394/1857 : H2/HI ratio in galaxies (Obreschkow+, 2009)
J/AJ/143/98 : Spectroscopy of star-forming regions in NGC 4194
(Weistrop+, 2012)
J/AJ/143/144 : ULX candidates in nearby Arp galaxies (Smith+, 2012)
J/MNRAS/426/2601 : CO lines in luminous IR galaxies (Papadopoulos+, 2012)
J/ApJ/829/78 : Dust properties of major-merger galaxy pairs
(Domingue+, 2016)
J/MNRAS/464/3882 : Mergers and galaxy-galaxy interactions (Weston+, 2017)
J/AJ/155/81 : Diffuse X-ray-emitting gas in major mergers (Smith+, 2018)
J/ApJ/855/49 : ALMA astrochemical obs. of the merger NGC 3256
(Harada+, 2018)
J/A+A/627/A107 : CO observations of major merger pairs at z=0
(Lisenfeld+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Galaxy name
18 I1 --- Stage [1/7] Merger stage (1)
20- 24 F5.1 Mpc Dist [9.8/184] Distance
26- 30 F5.2 [Lsun] logLFIR [8.4/12.19] Log far-infrared luminosity
from IRAS
32- 36 F5.2 [Lsun] logLK [9.06/12.36] Log near-infrared Ks band
luminosity from 2MASS
38- 43 F6.2 Msun/yr SFR [0.03/450.05] Star formation rate
45 A1 --- l_logLX(gas) [<] Limit flag on logLX(gas)
46- 50 F5.2 [10-7W] logLX(gas) [38.76/42.08] Thermal luminosity (in erg/s)
52- 61 A10 --- AGN Galaxy classification in the NASA
Extragalactic Database (NED) (2)
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Note (1): We classified the systems into seven merger stages based on their
morphologies. These stages are as follows:
1 = Separated but interacting pair with small or no tails;
2 = Separated pair with moderate or long tails;
3 = Pair with disks in contact;
4 = Common envelope, two nuclei, and tails;
5 = Single nucleus and two strong tails;
6 = Single nucleus but weak tails;
7 = Disturbed elliptical with small or no tails.
Note (2): 13 galaxies in the sample are classified in NED
(http://ned.ipac.caltech.edu) as Seyfert 1, Seyfert 2, or low-ionization
nuclear emission-line region (LINER) galaxies.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Galaxy name
18- 22 F5.2 [Msun] logM(H2)1 [7.39/10.56]? Molecular gas mass (1)
24- 28 F5.2 [Msun] logM(H2)2 [7.79/10.17]? Molecular gas mass (2)
30- 31 I2 --- CORef [1/15]? Reference for the original CO
measurement (3)
33- 37 F5.2 [yr-1] log(SFE)1 [-9.88/-7.19]? Log star formation
efficiency (1)
39- 43 F5.2 [yr-1] log(SFE)2 [-9.88/-6.67]? Log star formation
efficiency (2)
45- 49 F5.2 [Msun] logM(H1) [8.79/10.64]? Log global H I mass
51- 52 I2 --- HIRef [16/26]? Reference for the H I data (4)
54- 57 F4.2 [Msun] logMhot [6.85/9.75]? Log mass of the hot
X-ray-emitting gas
59- 63 F5.2 [-] log(Mhot/Mcold)1 [-2.52/-0.67]? Log hot-to-cold gas mass
ratio (1)
65- 69 F5.2 [-] log(Mhot/Mcold)2 [-2.52/-0.41]? Log hot-to-cold gas mass
ratio (2)
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Note (1): Assuming the standard Galactic CO/H2 ratio. SFE in this paper is
defined as SFR/MH2.
Note (2): Using the variable CO/H2 ratio (see the text for details). SFE is
defined as SFR/MH2.
Note (3): CO reference as follows:
1 = Mirabel et al. (1990A&A...236..327M 1990A&A...236..327M);
2 = Zhu et al. (1999AJ....118..145Z 1999AJ....118..145Z);
3 = Horellou et al. (1995A&A...298..743H 1995A&A...298..743H);
4 = Larson et al. (2016ApJ...825..128L 2016ApJ...825..128L);
5 = Wiklind et al. (1995A&A...297..643W 1995A&A...297..643W);
6 = Sanders et al. (1991ApJ...370..158S 1991ApJ...370..158S);
7 = Young et al. (1996AJ....112.1903Y 1996AJ....112.1903Y);
8 = Ueda et al. (2014ApJS..214....1U 2014ApJS..214....1U);
9 = Israel (2005A&A...438..855I 2005A&A...438..855I);
10 = Bushouse et al. (1999astro.ph.11186B 1999astro.ph.11186B);
11 = Solomon et al. (1997ApJ...478..144S 1997ApJ...478..144S);
12 = Georgakakis et al. (2001MNRAS.326.1431G 2001MNRAS.326.1431G);
13 = Papadopoulos et al. (2012, J/MNRAS/426/2601);
14 = Sage et al. (1992A&A...265...19S 1992A&A...265...19S);
15 = Elmegreen et al. (2016ApJ...823...26E 2016ApJ...823...26E).
Note (4): H I reference as follows:
16 = Doyle et al. (2005, J/MNRAS/361/34);
17 = Huchtmeier & Richter (1989gcho.book.....H 1989gcho.book.....H);
18 = Obreschkow & Rawlings (2009, J/MNRAS/394/1857);
19 = Martin et al. (1991A&A...245..393M 1991A&A...245..393M);
20 = Bushouse (1987ApJ...320...49B 1987ApJ...320...49B);
21 = Gordon et al. (2001MNRAS.326..578G 2001MNRAS.326..578G);
22 = van Driel et al. (2000A&AS..141..385V 2000A&AS..141..385V);
23 = Hibbard & van Gorkom (1996AJ....111..655H 1996AJ....111..655H);
24 = Cox & Sparke (2004AJ....128.2013C 2004AJ....128.2013C);
25 = English et al. (2003AJ....125.1134E 2003AJ....125.1134E);
26 = Fernandez et al. (2014AJ....147...74F 2014AJ....147...74F).
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Byte-by-byte Description of file: table3.dat table4.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 16 A16 --- Name Galaxy name
18- 33 A16 --- OName Other name of galaxy (only in
Table 3) (1)
35- 36 I2 h RAh Hour of Right Ascension (J2000)
38- 39 I2 min RAm Minute of Right Ascension (J2000)
41- 46 F6.3 s RAs Second of Right Ascension (J2000)
48 A1 --- DE- Sign of the Declination (J2000)
49- 50 I2 deg DEd Degree of Declination (J2000)
52- 53 I2 arcmin DEm Arcminute of Declination (J2000)
55- 59 F5.2 arcsec DEs Arcsecond of Declination (J2000)
61- 66 F6.2 arcsec Rmaj1 [8.95/143.52] Major axis radius
68- 73 F6.2 arcsec Rmin1 [4.4/112.32] Minor axis radius
75- 79 F5.2 kpc Rmaj2 [2.48/60] Major axis radius
81- 85 F5.2 kpc Rmin2 [0.85/49.64] Minor axis radius
87- 89 I3 deg PA [0/357] Position angle (2)
91- 92 I2 --- Na [1/13]? Number of annuli used in
the radial profile (only in
Table 3)
94- 98 I5 ct Counts [27/55121] Point-source
subtracted, background
subtracted 0.3-1.0 keV counts
in the final ellipse
100-102 I3 ct e_Counts [7/292] Uncertainty in Counts
104-105 A2 --- l_SB [=<] Limit flag on SB (only
in Table 4)
106-110 F5.1 10-10ph/s/cm2/arcsec2 SB [2.4/116]? 0.3-1.0keV surface
brightness (only in Table 4)
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Note (1): For systems with two distinct regions of diffuse emission, two
ellipses are given. In those cases, the name of the specific galaxy in the
pair associated with the particular region is identified in column "OName".
When the X-ray flux only comes from one galaxy in a pair, the name of that
individual galaxy is listed. If both galaxies in a pair are covered by a
single region of diffuse emission, both names are given in the column "OName".
If there is only one galaxy in the system, this column gives an alternative
name for the galaxy.
Note (2): The position angle of the major axis defined south of east as in
the ds9 software.
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History:
From electronic version of the journal
References:
Smith et al. Paper I. 2018AJ....155...81S 2018AJ....155...81S, Cat. J/AJ/155/81
(End) Tiphaine Pouvreau [CDS] 27-Nov-2019