J/AZh/94/648 Extragalactic star-forming regions (Smimova+, 2017)
Relation between the parameters of dust and of molecular and atomic gas in
extragalactic star-forming regions.
Smimova K.I., Murga M.S., Wiebe D.S., Sobolev A.M.
<Astron. Zh. 94, 648 (2017)>
=2017ARep...61..646S 2017ARep...61..646S
=2017AZh....94..648S 2017AZh....94..648S (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Molecular clouds
Photometry, millimetric/submm ; Carbon monoxide ; H I data
Abstract:
The relationships between atomic and molecular hydrogen and dust of
various sizes in extragalactic star-forming regions are considered,
based on observational data from the Spitzer and Herschel infrared
space telescopes, the Very Large Array (atomic hydrogen emission) and
IRAM (CO emission). The source sample consists of approximately 300
star-forming regions in 11 nearby galaxies. Aperture photometry has
been applied to measure the fluxes in eight infrared bands (3.6, 4.5,
5.8, 8, 24, 70, 100, and 160um), the atomic hydrogen 21 cm line, and
CO (2-1) line. The parameters of the dust in the starforming regions
were determined via synthetic-spectra fitting, such as the total dust
mass, the fraction of polycyclic aromatic hydrocarbons (PAHs), etc.
Comparison of the observed fluxes with the measured parameters shows
that the relationships between atomic hydrogen, molecular hydrogen,
and dust are different in low- and high-metallicity regions.
Low-metallicity regions contain more atomic gas, but less molecular
gas and dust, including PAHs. The mass of dust constitutes about 1% of
the mass of molecular gas in all regions considered. Fluxes produced
by atomic and molecular gas do not correlate with the parameters of
the stellar radiation, whereas the dust fluxes grow with increasing
mean intensity of stellar radiation and the fraction of enhanced
stellar radiation. The ratio of the fluxes at 8 and 24um, which
characterizes the PAH content, decreases with increasing intensity of
the stellar radiation, possibly indicating evolutionary variations of
the PAH content. The results confirm that the contribution of the 24um
emission to the total IR luminosity of extragalactic star-forming
regions does not depend on the metallicity.
Description:
We have considered the relationships between the emission of CO
molecules, atomic hydrogen, and dust at wavelengths of 8-160um,
using archival data on approximately 300 SFRs in 11 galaxies with
metallicities (12+log(O/H)) from 7.54 to 8.71.
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
galaxies.dat 65 11 Data on the studied galaxies
photom.dat 210 272 Photometry results for the 10 galaxies
--------------------------------------------------------------------------------
Byte-by-byte Description of file: galaxies.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Gal Galaxy name
13- 23 F11.7 deg RAdeg Right ascension (J2000)
25- 34 F10.7 deg DEdeg Declination (J2000)
36- 39 F4.1 Mpc Dist Distance
41 A1 --- r_Dist Distance reference (1)
43- 52 A10 --- MType Morphological type
54- 57 F4.2 --- Abd Abundance, 12+log(O/H)
59- 60 I2 --- N1 Number of selected regions
62 A1 --- --- [(]
63- 64 I2 --- N2 Number of regions where we could determine the
dust parameters by means of fitting their spectra
65 A1 --- --- [)]
--------------------------------------------------------------------------------
Note (1): References as follows:
a = Rodriguez et al. (2014AJ....148..107R 2014AJ....148..107R)
b = Tully et al. (2013, Cat. J/AJ/146/86)
c = Tully et al. (2009AJ....138..323T 2009AJ....138..323T)
d = Russell (2002ApJ...565..681R 2002ApJ...565..681R)
e = Courtois & Tully (2012ApJ...749..174C 2012ApJ...749..174C)
f = Jacobs et al. (2009, Cat. J/AJ/138/332)
g = Sorce et al. (2014, Cat. J/MNRAS/444/527)
--------------------------------------------------------------------------------
Byte-by-byte Description of file: photom.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 11 A11 --- Gal Galaxy name
13- 14 I2 --- Seq Star-forming region sequential number
within the galaxy
16- 25 F10.6 deg RAdeg Right ascension (J2000)
27- 35 F9.6 deg DEdeg Declination (J2000)
37- 40 F4.1 arcsec R Radius
42- 47 F6.2 mJy F3.6 ?=0 Flux at 3.6um
49- 53 F5.2 mJy e_F3.6 ?=0 rms uncertainty on F3.6
55- 60 F6.2 mJy F4.5 ?=0 Flux at 4.5um
62- 66 F5.2 mJy e_F4.5 ?=0 rms uncertainty on F4.5
68- 73 F6.2 mJy F5.8 ?=0 Flux at 5.8um
75- 79 F5.2 mJy e_F5.8 ?=0 rms uncertainty on F5.8
81- 86 F6.2 mJy F8.0 ?=0 Flux at 8.0um
88- 92 F5.2 mJy e_F8.0 ?=0 rms uncertainty on F8.0
94- 99 F6.2 mJy F8.0afe ?=0 Flux at 8.0um only from PAH
101-106 F6.2 mJy e_F8.0afe ?=0 rms uncertainty on Fafe8.0
108-113 F6.2 mJy F24 ?=0 Flux on 24um
115-119 F5.2 mJy e_F24 ?=0 rms uncertainty on F24
121-126 F6.2 mJy F24ns ?=0 Flux on 24um only from very small
grains (VSG)
128-132 F5.2 mJy e_F24ns ?=0 rms uncertainty on F24ns
134-140 F7.2 mJy F70 ?=0 Flux at 70um
142-147 F6.2 mJy e_F70 ?=0 rms uncertainty on F70
149-156 F8.2 mJy F100 ?=0 Flux at 100um
158-163 F6.2 mJy e_F100 ?=0 rms uncertainty on F100
165-172 F8.2 mJy F160 ?=0 Flux at 160um
174-179 F6.2 mJy e_F160 ?=0 rms uncertainty on F160
181-187 F7.2 Jy.km/s FCO ?=0 CO flux
189-195 F7.2 Jy.km/s e_FCO ?=0 rms uncertainty on FCO
197-203 F7.2 Jy.km/s FHI ?=0 HI flux
205-210 F6.2 Jy.km/s e_FHI ?=0 rms uncertainty on FHI
--------------------------------------------------------------------------------
History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 08-Sep-2017