J/ApJ/884/136 PAH features of star-forming gal. using Spitzer/IRS (Xie+, 2019)
A new calibration of star formation rate in galaxies based on polycyclic
aromatic hydrocarbon emission.
Xie Y., Ho L.C.
<Astrophys. J., 884, 136 (2019)>
=2019ApJ...884..136X 2019ApJ...884..136X
ADC_Keywords: Galaxies, spectra; Infrared sources; Redshifts; Stars, masses;
Abundances; Extinction
Keywords: dust, extinction ; galaxies: dwarf ; galaxies: formation ;
galaxies: starburst
Abstract:
Polycyclic aromatic hydrocarbon (PAH) emission has long been proposed
to be a potential star formation rate indicator, as it arises from the
photodissociation region bordering the Stromgren sphere of young,
massive stars. We apply a recently developed technique of mid-infrared
spectral decomposition to obtain a uniform set of PAH measurements
from Spitzer low-resolution spectra of a large sample of star-forming
galaxies spanning a wide range in stellar mass
(M*∼106-1011.4M☉) and star formation rate
(∼0.1-2000M☉/yr). High-resolution spectra are also analyzed to
measure [NeII]12.8µm and [NeIII]15.6µm, which effectively trace
the Lyman continuum. We present a new relation between PAH luminosity
and star formation rate based on the [NeII] and [NeIII] lines.
Calibrations are given for the integrated 5-15µm PAH emission, the
individual features at 6.2, 7.7, 8.6, and 11.3µm, as well as
several mid- infrared bandpasses sensitive to PAH. We confirm that PAH
emission is suppressed in low-mass dwarf galaxies, and we discuss the
possible physical origin of this effect.
Description:
Our calibration data are gathered from the literature and from the
Spitzer archive. The sample comprises local dwarf galaxies, normal
star-forming galaxies, and starburst galaxies.
We require the selected galaxies to have high-quality IRS
low-resolution and high-resolution spectra, the former providing the
broad spectral coverage necessary to cover the widespread PAH emission
and the latter having sufficient resolution to properly deblend
[NeII]12.8um and [NeIII]15.6um from neighboring contaminating
features. After extensive experimentation with the IRS database, we
determined that reliable measurements can be obtained from spectra
that have a minimum signal-to-noise ratio per pixel of ∼1.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 175 226 Physical properties of the sample
table2.dat 116 226 PAH luminosity in different bands
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See also:
J/ApJ/511/639 : Abundances in blue compact galaxies (Izotov+, 1999)
J/ApJ/522/113 : 1Jy IRAS galaxies optical spectroscopy (Veilleux+, 1999)
J/ApJ/648/987 : UV through far-IR analysis of M81 (Perez-Gonzalez+, 2006)
J/ApJ/671/323 : Spitzer Spectra of a 10mJy galaxy sample (Houck+, 2007)
J/ApJ/656/770 : Mid-IR spectrum of star-forming galaxies (Smith+, 2007)
J/ApJ/686/127 : Starbursts luminosities based on PAH (Weedman+, 2008)
J/ApJ/703/517 : The Spitzer Local Volume Legacy: IR photometry (Dale+, 2009)
J/ApJ/703/1672 : Far-IR and Hα fluxes in galaxies (Kennicutt+, 2009)
J/ApJ/705/885 : PAH in galaxies at z∼0.1 (O'Dowd+, 2009)
J/ApJ/692/556 : Star forming galaxy templates (Rieke+, 2009)
J/ApJ/701/1398 : SFR for starburst galaxies (Sargsyan+, 2009)
J/ApJ/714/1256 : Far-IR star formation rate indicators (Calzetti+, 2010)
J/ApJ/719/1191 : Mid-IR indicators of SF and AGN in galaxies (Treyer+, 2010)
J/ApJ/741/79 : The Spitzer-SDSS-GALEX Spectroscopic Survey (O'Dowd+, 2011)
J/ApJ/819/L27 : Stellar masses of optical & IR QSO hosts (Zhang+, 2016)
J/ApJ/847/136 : Hβ to N2 line fluxes of nearby galaxies (Brown+, 2017)
J/ApJ/870/104 : 1-500um obs. of nearby luminous IR galaxies (Shangguan+, 2019)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 25 A25 --- ID Object identifier
27 A1 --- f_ID [*] Flag on ID (1)
29- 33 F5.3 --- z [0.001/0.264] Redshift
35- 38 I4 Mpc DL [9/1380] Luminosity distance
40- 44 F5.2 [Msun] logM* [6.12/11.36] Log stellar mass
46- 49 F4.2 [Msun] e_logM* [0.07/0.32] Lower uncertainty in logM*
51- 54 F4.2 [Msun] E_logM* [0.04/0.32] Upper uncertainty in logM*
56- 59 F4.2 [-] Z [7.18/8.9] Metallicity
61- 64 F4.2 [-] e_Z [0.01/0.15]? Lower uncertainty in logLNe
66- 69 F4.2 [-] E_Z [0.01/0.15]? Upper uncertainty in Ne3/Ne2
71 A1 --- r_Z Reference for metallicity (2)
73 A1 --- l_logt9.7 Limit flag on logt9.7
74- 78 F5.2 [-] logt9.7 [-4/0.77] Dust extinction at 9.7 microns
80- 83 F4.2 [-] e_logt9.7 [0.01/5.4]? Lower uncertainty in logt9.7
85- 88 F4.2 [-] E_logt9.7 [0.01/5.4]? Upper uncertainty in logt9.7
90 A1 --- l_logLNe Limit flag on logLNe
91- 95 F5.2 [10-7W] logLNe [38.0/43.83] Log [NeII]_[NeIII]
luminosity; erg/s
97-100 F4.2 [10-7W] e_logLNe [0.01/0.8]? Lower uncertainty in logLNe
102-105 F4.2 [10-7W] E_logLNe [0.01/0.8]? Upper uncertainty in logLNe
107 A1 --- f_Ratio Limit or approximate flag on Ratio
108-112 F5.2 --- Ratio [0.06/19.5] Luminosity ratio
of [NeIII]/[NeII]
114-117 F4.2 --- e_Ratio [0.01/4.5]? Lower uncertainty in Ratio
119-122 F4.2 --- E_Ratio [0.01/4.5]? Upper uncertainty in Ratio
124-127 F4.2 --- fp [0.02/0.94] Fractional abundance of neon
in [NeII] state
129-132 F4.2 --- e_fp [0.01/0.4]? Lower uncertainty in fp
134-137 F4.2 --- E_fp [0.01/0.4]? Upper uncertainty in fp
139-142 F4.2 --- f2p [0.02/1] Fractional abundance of neon
in [NeIII] state
144-147 F4.2 --- e_f2p [0.01/0.4]? Lower uncertainty in f2p
149-152 F4.2 --- E_f2p [0.01/0.4]? Upper uncertainty in f2p
154 A1 --- l_logSFR Limit flag on logSFR
155-159 F5.2 [Msun/yr] logSFR [-1.5/3.3] Log Star Formation Rate
161-164 F4.2 [Msun/yr] e_logSFR [0.01/0.9]? Lower uncertainty in logSFR
166-169 F4.2 [Msun/yr] E_logSFR [0.01/0.9]? Upper uncertainty in logSFR
171-175 A5 --- Class Galaxy type (G1)
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Note (1): Flag as follows:
* = an object whose stellar mass is calculated in the current work.
Note (2): We collect the metallicity measurements from references as follows:
a = Wu et al. (2006ApJ...639..157W 2006ApJ...639..157W);
b = Izotov & Thuan (1999, J/ApJ/511/639);
c = Izotov et al. (2012MNRAS.427.1229I 2012MNRAS.427.1229I);
d = Berg et al. (2016ApJ...827..126B 2016ApJ...827..126B); and
e = Kobulnicky & Skillman (1996ApJ...471..211K 1996ApJ...471..211K).
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 25 A25 --- ID Object identifier
27 A1 --- l_logL6.2 Limit flag on logL6.2
28- 32 F5.2 [10-7W] logL6.2 [37.73/44.2] Log luminosity of 6.2 micron
PAH feature (1)
34- 37 F4.2 [10-7W] e_logL6.2 [0.01/0.15]? Lower uncertainty in logL6.2
39- 42 F4.2 [10-7W] E_logL6.2 [0.01/0.15]? Upper uncertainty in logL6.2
44 A1 --- l_logL7.7 Limit flag on logL7.7
45- 49 F5.2 [10-7W] logL7.7 [38.21/45.39] Log luminosity of 7.7 micron
PAH feature (1)
51- 54 F4.2 [10-7W] e_logL7.7 [0.01/0.14]? Lower uncertainty in logL7.7
56- 59 F4.2 [10-7W] E_logL7.7 [0.01/0.14]? Upper uncertainty in logL7.7
61 A1 --- l_logL8.6 Limit flag on logL8.6
62- 66 F5.2 [10-7W] logL8.6 [37.72/44.76] Log luminosity of 8.6 micron
PAH feature (1)
68- 71 F4.2 [10-7W] e_logL8.6 [0.01/0.15]? Lower uncertainty in logL8.6
73- 76 F4.2 [10-7W] E_logL8.6 [0.01/0.15]? Upper uncertainty in logL8.6
78 A1 --- l_logL11.3 Limit flag on logL11.3
79- 83 F5.2 [10-7W] logL11.3 [37.56/44.79] Log luminosity of 11.3 micron
PAH feature (1)
85- 88 F4.2 [10-7W] e_logL11.3 [0.01/0.15]? Lower uncertainty in logL11.3
90- 93 F4.2 [10-7W] E_logL11.3 [0.01/0.15]? Upper uncertainty in logL11.3
95 A1 --- l_logL5-15 Limit flag on logL5-15
96- 100 F5.2 [10-7W] logL5-15 [38.76/45.87] Log luminosity of PAH in
5-15 micron band (1)
102- 105 F4.2 [10-7W] e_logL5-15 [0.01/0.13]? Lower uncertainty in logL5-15
107- 110 F4.2 [10-7W] E_logL5-15 [0.01/0.13]? Upper uncertainty in logL5-15
112- 116 A5 --- Class Galaxy type (G1)
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Note (1): In erg/s units.
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Global note:
Note (G1): Classified based on bolometric luminosity as follows:
SFG = star-forming galaxy (196 occurrences);
BCD = blue compact dwarf (17 occurrences);
ULIRG = ultraluminous infrared galaxy (13 occurrences).
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 25-Mar-2021