J/ApJS/203/3 Spectroscopy of 39 IRAS 1Jy sample ULIRG (Soto+, 2012)
Gas excitation in ULIRGs: maps of diagnostic emission-line ratios in space and
velocity.
Soto K.T., Martin C.L.
<Astrophys. J. Suppl. Ser., 203, 3 (2012)>
=2012ApJS..203....3S 2012ApJS..203....3S
ADC_Keywords: Galaxies, IR ; Spectroscopy ; Velocity dispersion
Keywords: galaxies: active - galaxies: evolution - galaxies: formation -
galaxies: starburst
Abstract:
Emission-line spectra extracted at multiple locations across 39
ultraluminous infrared galaxies have been compiled into a
spectrophotometric atlas. Line profiles of Hα, [NII], [SII],
[OI], Hβ, and [OIII] are resolved and fit jointly with common
velocity components. Diagnostic ratios of these line fluxes are
presented in a series of plots, showing how the Doppler shift, line
width, gas excitation, and surface brightness change with velocity at
fixed position and also with distance from the nucleus. One general
characteristic of these spectra is the presence of shocked gas
extending many kiloparsecs from the nucleus. In some systems, the
rotation curves of the emitting gas indicate motions that suggest gas
disks, which are most frequent at early merger stages. At these early
merger stages, the emission line ratios indicate the presence of
shocked gas, which may be triggered by the merger event. We also
report the general characteristics of the integrated spectra.
Description:
Moderate-resolution spectra were obtained at the Keck Observatory with
the Echellete Spectrograph and Imager (ESI) under average seeing of
0.8". The observations and data reduction are described in Martin
(2005ApJ...621..227M 2005ApJ...621..227M, 2006ApJ...647..222M 2006ApJ...647..222M).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 36 39 Sample and morphology of Ultra Luminous Infra-Red
Galaxies (ULIRGs)
table2.dat 147 430 Component velocities and fluxes
table4.dat 66 242 Shock velocities for identified shock components
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See also:
J/AJ/132/2596 : Spectroscopy of Ultraluminous IR galaxies (Darling+, 2006)
J/AJ/131/1942 : 2MASS observations of IRAS 1Jy ULIRGs (Chen+, 2006)
J/A+A/409/115 : VLA imaging of IRAS 1 Jy ULIRG sample (Nagar+, 2003)
J/ApJS/143/315 : IRAS 1Jy sample of ULIRGs. II. (Veilleux+, 2002)
J/ApJS/143/277 : IRAS 1Jy sample of ultraluminous galaxies. I. (Kim+, 2002)
J/ApJ/522/113 : 1Jy IRAS galaxies optical spectroscopy (Veilleux+, 1999)
J/MNRAS/279/459 : Ultraluminous IRAS galaxies (Clements+ 1996)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- IRAS IRAS name (HHMMm+DDMM) (G1)
12- 15 A4 --- IC Merger classification (Veilleux et al. 2002,
Cat. J/ApJS/143/315) (2)
17 A1 --- f_IC [a] Estimated IC (1)
19- 23 F5.2 [Lsun] log(LIR) IR luminosity (Murphy+ 1996AJ....111.1025M 1996AJ....111.1025M)
25- 30 F6.4 --- z [0.04/0.16] Redshift
32- 36 F5.1 deg PA [-90/167] Position angle of slit
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Note (1): Classifications estimated from r-band images and Murphy et al.
(1996AJ....111.1025M 1996AJ....111.1025M).
Note (2): Classification phases:
I = first approach (disks relatively unperturbed)
II = first contact (disks overlap but bars and tidal tails not formed)
III = pre-merger (2 identifiables nuclei) wide (IIIa) and close (IIIb)
IV = merger (nuclei apparently coalesced), diffuse (IVa) and compact (IVb)
V = old merger (disturbed central morphologie but no unmistakable
sign of tidal tails)
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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- 10 A10 --- IRAS IRAS galaxy identifier (G1)
12- 13 I2 --- ApN [0/12] Aperture number
15 A1 --- ex [hsu] Excitation classification (1)
17- 22 F6.2 kpc r-rnuc [-16/16] Distance from sampled region to
nucleus
24- 27 F4.2 kpc Ap Size of aperture
29- 35 F7.2 km/s Vel Line of sight velocity (2)
37- 42 F6.3 km/s e_Vel Uncertainty in Vel
44- 50 F7.2 km/s sigma [8.9/1380] Velocity dispersion (2)
52- 57 F6.3 km/s e_sigma Uncertainty in sigma
59- 66 F8.3 10-20W/m2 FHa ? Hα flux emission (2)
68- 72 F5.3 10-20W/m2 e_FHa ? Uncertainty in FHa
74- 80 F7.3 10-20W/m2 F[NII] ? [NII] flux emission (2)
82- 88 F7.4 10-20W/m2 e_F[NII] ? Uncertainty in F[NII]
90- 96 F7.3 10-20W/m2 F[SII] ? [SII] flux emission (2)
98-103 F6.3 10-20W/m2 e_F[SII] ? Uncertainty in F[SII]
105-111 F7.3 10-20W/m2 F[OI] ? [OI] flux emission (2)
113-117 F5.3 10-20W/m2 e_F[OI] ? Uncertainty in F[OI]
119-125 F7.3 10-20W/m2 FHb ? Hβ flux emission (2)
127-131 F5.3 10-20W/m2 e_FHb ? Uncertainty in FHb
133-140 F8.3 10-20W/m2 F[OIII] ? [OIII] flux emission (2)
142-147 F6.3 10-20W/m2 e_F[OIII] ? Uncertainty in F[OIII]
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Note (1): Classification as follows:
h = a component with HII-like line ratios;
s = components with line ratios indicative of shock;
u = an unclear component where the errors in the flux ratio make the
measurement consistent with either interpretation.
Note (2): Of fitted spectral component. Fluxes in units of 1e-17erg/s/cm2.
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- IRAS IRAS galaxy identifier (G1)
12- 13 I2 --- ApN Aperture number
15- 21 F7.2 km/s Vel Line of sight velocity (1)
23- 28 F6.3 km/s e_Vel Uncertainty in Vel
30- 36 F7.2 km/s sigma [16/733] Velocity dispersion (1)
38- 42 F5.2 km/s e_sigma Uncertainty in sigma
44- 46 I3 km/s v[NII] [50/700] Velocity of shock front (2)
48- 50 I3 km/s e_v[NII] Uncertainty in v[NII]
52- 54 I3 km/s v[SII] [50/700]? Velocity of shock front (3)
56- 58 I3 km/s e_v[SII] ? Uncertainty in v[SII]
60- 62 I3 km/s v[OI] [50/700]? Velocity of shock front (4)
64- 66 I3 km/s e_v[OI] ? Uncertainty in v[OI]
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Note (1): Of the fit component.
Note (2): Measured from the ratios log([OIII]/Hα) vs log([NII]/Hα)
from shock grids of Allen et al. (2008ApJS..178...20A 2008ApJS..178...20A).
Note (3): Measured from the ratios log([OIII]/Hα) vs log([SII]/Hα)
from shock grids of Allen et al. (2008ApJS..178...20A 2008ApJS..178...20A).
Note (4): Measured from the ratios log([OIII]/Hα) vs log([OI]/Hα)
from shock grids of Allen et al. (2008ApJS..178...20A 2008ApJS..178...20A).
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Global notes:
Note (G1):
In tables 1, 2 and 4, IRAS 15462-0405 is assumed to be a
misprint for 15462-0450; corrected at CDS.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 03-Dec-2012