J/ApJ/846/32 Herschel FIR spectra of GOALS galaxies (Diaz-Santos+, 2017)
A Herschel/PACS far-infrared line emission survey of local luminous infrared
galaxies.
Diaz-Santos T., Armus L., Charmandaris V., Lu N., Stierwalt S., Stacey G.,
Malhotra S., van der Werf P.P., Howell J.H., Privon G.C., Mazzarella J.M.,
Goldsmith P.F., Murphy E.J., Barcos-Munoz L., Linden S.T., Inami H.,
Larson K.L., Evans A.S., Appleton P., Iwasawa K., Lord S., Sanders D.B.,
Surace J.A.
<Astrophys. J., 846, 32 (2017)>
=2017ApJ...846...32D 2017ApJ...846...32D
ADC_Keywords: Galaxies, IR ; Spectra, infrared ; Active gal. nuclei ; Surveys
Keywords: galaxies: evolution; galaxies: ISM; galaxies: nuclei;
galaxies: starburst; infrared: galaxies
Abstract:
We present an analysis of [OI]63, [OIII]88, [NII]122, and
[CII]158 far-infrared (FIR) fine-structure line observations
obtained with Herschel/PACS, for ∼240 local luminous infrared galaxies
(LIRGs) in the Great Observatories All-sky LIRG Survey. We find
pronounced declines ("deficits") of line-to-FIR continuum emission for
[NII]122, [OI]63, and [CII]158 as a function of FIR color and
infrared luminosity surface density, ΣIR. The median electron
density of the ionized gas in LIRGs, based on the
[NII]122/[NII]205 ratio, is ne=41cm-3. We find that the
dispersion in the [CII]158 deficit of LIRGs is attributed to a
varying fractional contribution of photodissociation regions (PDRs) to
the observed [CII]158 emission,
f([CII]158PDR)=[CII]158PDR/[CII]158, which increases from
∼60% to ∼95% in the warmest LIRGs. The [OI]63/[CII]158PDR ratio
is tightly correlated with the PDR gas kinetic temperature in sources
where [OI]63 is not optically thick or self-absorbed. For each
galaxy, we derive the average PDR hydrogen density, nH, and
intensity of the interstellar radiation field, G, in units of G0 and
find G/nH ratios of ∼0.1-50G0.cm3, with ULIRGs populating the
upper end of the distribution. There is a relation between G/nH and
ΣIR, showing a critical break at
ΣIR*∼5x1010L☉/kpc2. Below ΣIR*, G/nH
remains constant, ∼0.32G0.cm3, and variations in ΣIR are
driven by the number density of star-forming regions within a galaxy,
with no change in their PDR properties. Above ΣIR*, G/nH
increases rapidly with ΣIR, signaling a departure from the
typical PDR conditions found in normal star-forming galaxies toward
more intense/harder radiation fields and compact geometries typical of
starbursting sources.
Description:
We have obtained FIR spectroscopic observations for 200 luminous
infrared galaxies (LIRG) systems from the Great Observatories All-Sky
LIRG Survey (GOALS; Armus+ 2009PASP..121..559A 2009PASP..121..559A) using the Integral
Field Spectrometer (IFS) of the PACS instrument on board Herschel.
Since some targets contain multiple components, there are 241
individual galaxies with available spectra in at least one emission
line. Most of the data were collected as part of our OT1 and OT2
programs (OT1larmus1, OT2larmus1; P.I.: L. Armus), accounting for
more than 200hr of observing time in total. Additional observations
that are publicly available in the Herschel archive were included from
various projects. The main programs from where these complementary
data were gathered are KPGTesturm1 (P.I.: E. Sturm), KPOTpvanderw1
(PI: P. van der Werf), and OT1dweedman1 (P.I.: D. Weedman). The IFS
on PACS is able to perform simultaneous spectroscopy in the 51-73 or
70-105um and the 102-210um ranges.
In addition to the PACS/IFS spectra, we obtained observations of the
[NII]205 emission line using the SPIRE FTS for 121 galaxies in the
GOALS sample (Lu+ 2017, J/ApJS/230/1 ; OT1nlu1; P.I.: N. Lu).
As part of the Spitzer GOALS legacy program, all galaxies observed
with Herschel/PACS have available Spitzer/IRS low-resolution, R∼60-120
(SL module: 5.2-14.5um; LL module: 14-38um), and medium-resolution,
R∼600 (SH module: 9.9-19.6um; LH module: 18.7-37.2um), slit spectroscopy.
File Summary:
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FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
galaxies.dat 20 241 List of individual galaxies; table added by CDS
table1.dat 146 716 Emission line and continuum data for 241 galaxies
table2.dat 77 231 AGN fractions
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See also:
VI/139 : Herschel Observation Log (Herschel Science Centre, 2013)
J/AJ/126/1607 : IRAS Revised Bright Galaxy Sample (Sanders+, 2003)
J/ApJS/178/280 : Compendium of ISO far-IR extragalactic data (Brauher+, 2008)
J/ApJS/184/1 : Molecular clouds in the LMC by NANTEN. II. (Kawamura+, 2009)
J/ApJS/182/628 : Spitzer quasar and ULIRG evolution study (Veilleux+, 2009)
J/ApJ/723/993 : Spatial extent of (U)LIRGs in the MIR. I. (Diaz-Santos+, 2010)
J/ApJ/715/572 : GOALS UV and FIR properties (Howell+, 2010)
J/ApJ/741/32 : Spatial extent of (U)LIRGs in MIR. II. (Diaz-Santos+, 2011)
J/A+A/533/A119 : GOODS-Herschel North and South catalogs (Elbaz+, 2011)
J/A+A/528/A35 : Infrared luminosity in GOODS fields (Magnelli+, 2011)
J/ApJ/761/37 : CO obs. in giant molecular clouds of M33 (Miura+, 2012)
J/ApJ/774/68 : [CII]157.7um feature in LIRGs (Diaz-Santos+, 2013)
J/ApJ/777/156 : Spitzer/IRS spectra of GOALS luminous IR gal. (Inami+, 2013)
J/ApJ/768/102 : I-band GALFIT analysis of luminous IR galaxies (Kim+, 2013)
J/ApJS/206/1 : Mid-IR properties of GOALS nearby LIRGs (Stierwalt+, 2013)
J/A+A/566/A45 : Orion optical-depth and column-density maps (Lombardi+, 2014)
J/ApJ/790/124 : Dust and gas physics of the GOALS sample (Stierwalt+, 2014)
J/A+A/578/A53 : Spectroscopy of Herschel Dwarf Galaxy Survey (Cormier+, 2015)
J/ApJ/814/133 : Herschel Galactic plane survey of [NII] (Goldsmith+, 2015)
J/A+A/575/A17 : NGC 891 Herschel PACS and SPIRE spectroscopy (Hughes+, 2015)
J/A+A/591/A136 : Galaxies & QSOs FIR size and surface brightness (Lutz+, 2016)
J/ApJ/819/69 : [NII]205um emission in local luminous IR gal. (Zhao+, 2016)
J/ApJS/229/25 : GOALS sample PACS and SPIRE fluxes (Chu+, 2017)
J/ApJS/230/1 : Herschel SPIRE/FTS 194-671um survey of GOALS LIRGs (Lu+, 2017)
http://archives.esac.esa.int/hsa/whsa/ : ESA Herschel Science Archive home page
Byte-by-byte Description of file: galaxies.dat
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Bytes Format Units Label Explanations
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1- 3 I3 --- ID [0/240] Source identification number
5- 20 A16 --- Target Target identifier
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Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1 I1 --- Line [1/4] Line code (1)
3- 5 I3 --- ID [0/240]? Source identification number
7- 22 A16 --- Target Target identifier
24 I1 --- XRas [0/2] X raster used to obtain the galaxy
measurements
26 I1 --- YRas [0/2] Y raster used to obtain the galaxy
measurements
28 I1 --- XCS [1/3] X reference central spaxel of raster (2)
30 I1 --- YCS [0/4] Y reference central spaxel of raster (2)
32- 33 I2 h RAh Hour of Right Ascension (J2000) (3)
35- 36 I2 min RAm Minute of Right Ascension (J2000) (3)
38- 42 F5.2 s RAs Second of Right Ascension (J2000) (3)
44 A1 --- DE- Sign of the Declination (J2000) (3)
45- 46 I2 deg DEd Degree of Declination (J2000) (3)
48- 49 I2 arcmin DEm Arcminute of Declination (J2000) (3)
51- 54 F4.1 arcsec DEs Arcsecond of Declination (J2000) (3)
56- 59 F4.2 arcsec Dist [0.0/5.3] Distance from [OI] (63um) continuum
peak to reference spaxel
61- 66 F6.2 10-17W/m2 CFlux [-17.2/959.5] Central line flux (4)
68- 72 F5.2 10-17W/m2 e_CFlux [0/15.5]? Uncertainty in CFlux
74- 79 I6 mJy CCFlux [-855/130896] Flux density of continuum (5)
81- 83 I3 mJy e_CCFlux [6/513] Uncertainty in CCFlux
85 I1 --- Comp [0/1] Companion galaxy within reference
spaxel (1=yes)
87 I1 --- R-C [0/1] Reference and continuum spaxels
coincide (1=yes)
89 I1 --- R-L [0/1] Reference and line spaxels coincide
(1=yes)
91 I1 --- C-L [0/1] Continuum and line spaxels coincide
(1=yes)
93- 99 F7.2 10-17W/m2 BFlux [-7.3/3131] Galaxy-integrated line flux (6)
101-105 F5.2 10-17W/m2 e_BFlux [0/32.3]? Uncertainty in BFlux
107-112 I6 mJy BCFlux [-855/272584] Galaxy-integrated flux density
of continuum (7)
114-117 I4 mJy e_BCFlux [9/1970] Uncertainty in BCFlux
119 A1 --- Best Best galaxy-integrated measurement type (8)
121-130 A10 --- ObsId Herschel observation ID of dataset used
132-146 A15 --- PID Program identifier of AOR
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Note (1): Code as follows:
1 = [OI] (63um);
2 = [OIII] (88um);
3 = [NII] (122um);
4 = [CII] (158um).
Note (2): Defined as the closest spaxel to the 63#m continuum peak of the
galaxy within the 5x5 PACS FoV in the raster of the AOR.
Note (3): Of the reference spaxel.
Note (4): Measured from the reference spaxel (a) method. A negative indicates
an upper limit and the uncertainties do not include the absolute
photometric calibration uncertainty.
Note (5): Under the line measured from the reference spaxel (a) method.
A negative indicates an upper limit and the uncertainties do not
include the absolute photometric calibration uncertainty.
Note (6): Of the line measured from the best aperture. A negative indicates
an upper limit and the uncertainties do not include the absolute
photometric calibration uncertainty.
Note (7): Under the line measured from the best aperture. A negative indicates
an upper limit and the uncertainties do not include the absolute
photometric calibration uncertainty.
Note (8): Methods are (a), (b) or (c) (see text for details). Associated
galaxy-integrated infrared luminosity (LIR) and luminosity
surface densities (ΣIR) (the latter defined as
(LIR/2)πR270um,eff) can be found at
http://goals.ipac.caltech.edu/
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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- 3 I3 --- ID [0/240]? Source identification number
5 A1 --- l_NeV/NeII [-] Upper limit flag on NeV/NeII
6- 9 F4.2 --- NeV/NeII [0/1]? MIR AGN fraction from
[NeV](14.3um)/[NeII](12.8um) ratio
diagnostic
11- 14 F4.2 --- e_NeV/NeII [0.01/0.05]? Uncertainty in NeV/NeII
16 A1 --- l_OIV/NeII [-] Upper limit flag on OIV/NeII
17- 20 F4.2 --- OIV/NeII [0/1]? MIR AGN fraction from
[OIV](25.9um)/[NeII](12.8um) ratio
diagnostic
22- 25 F4.2 --- e_OIV/NeII [0.01/0.04]? Uncertainty in OIV/NeII
27 A1 --- l_6.2PAH [-] Lower limit flag on 6.2PAH
28- 31 F4.2 --- 6.2PAH [0/1]? MIR AGN fraction from 6.2um PAH
equivalent width
33- 36 F4.2 --- e_6.2PAH [0.01/0.08]? Uncertainty in 6.2PAH
38- 41 F4.2 --- S30/S15 [0/1]? MIR AGN fraction from S30/S15
ratio diagnostic
43- 46 F4.2 --- e_S30/S15 [0.01/0.4]? Uncertainty in S30/S15
48 A1 --- l_Laurent [-] Lower limit flag on Laurent
49- 52 F4.2 --- Laurent [0.1/1]? MIR AGN fraction from Laurent
diagram diagnostic
54- 57 F4.2 --- e_Laurent [0.01/0.2]? Uncertainty in Laurent
59- 62 F4.2 --- [0/1] Average MIR AGN fraction based
on all diagnostics
64- 67 F4.2 --- e_ [0/0.4] Uncertainty in
69- 72 F4.2 --- Bol [0/1] Average bolometric AGN fraction based
on all diagnostics (1)
74- 77 F4.2 --- e_Bol [0/0.3] Uncertainty in Bol
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Note (1): The bolometric fractions based on individual diagnostics can be
found at: http://goals.ipac.caltech.edu/
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History:
From electronic version of the journal
(End) Prepared by [AAS], Emmanuelle Perret [CDS] 12-Apr-2018