J/A+A/590/A67 Ionized gas maps of local U/LIRGs (Piqueras-Lopez+, 2016)
VLT-SINFONI sub-kpc study of the star formation in local LIRGs and ULIRGs:
Analysis of the global ΣSFR and characterisation of individual
star-forming clumps.
Piqueras-Lopez J., Colina L., Arribas S., Pereira-Santaella M.,
Alonso-Herrero A.
<Astron. Astrophys. 590, A67 (2016)>
=2016A&A...590A..67P 2016A&A...590A..67P (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Galaxies, IR ; Galaxies, photometry ;
Photometry, hydrogen-line ; Spectrophotometry
Keywords: galaxies: general - galaxies: evolution - galaxies: structure -
galaxies: star formation - infrared: ISM - infrared: galaxies
Abstract:
We present a 2D study of star formation at kpc and sub-kpc scales of a
sample of local (z<0.1) U/LIRGs, based on near-IR VLT-SINFONI
observations. We obtained integrated measurements of the star
formation rate (SFR) and star formation rate surface density, together
with their 2D distributions, based on Br_gamma and Pa_alpha emission.
We observe a tight linear correlation between the SFR derived from our
extinction-corrected measurements and that derived from 24 micron
data, and a reasonable agreement with SFR derived from total IR
luminosity. Our near-IR measurements are on average a factor 3 larger
than optical SFR, even when extinction corrections are applied. We
found that LIRGs have a median-observed star formation rate surface
density of 1.72M☉/yr/kpc2 for the extinction-corrected
distribution, whilst ULIRGs have 0.23M☉/yr/kpc^2, respectively.
These median values for ULIRGs increase up to 2.90M☉/yr/kpc2,
when only their inner regions, covering the same size as the average
FoV of LIRGs, are considered. We identified a total of 95 individual
SF clumps in our sample, with sizes within 60-1500pc, and
extinction-corrected Pa_alpha luminosities of 105-108L☉.
Star-forming clumps in LIRGs are about ten times larger and thousands
of times more luminous than typical clumps in spiral galaxies. Clumps
in ULIRGs have sizes similar (x0.5-1) to those of high-z clumps,
having Pa_alpha luminosities similar to some high-z clumps, and about
10 times less luminous than the most luminous high-z clumps identified
so far. We also observed a change in the slope of the L-r relation. A
likely explanation is that most luminous galaxies are interacting and
merging, and therefore their size represents a combination of the
distribution of the star-forming clumps within each galaxy in the
system plus the effect of the projected distance.
Description:
These are the emission line maps used in the paper, based on data
obtained with VLT/SINFONI. Included are the flux and flux error maps
for the Brackett gamma (LIRGs) and Paschen alpha (ULIRGs) lines. Units
are in erg/s/cm2. See the paper and references therein for a full
description.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 99 34 List of fits images
fits/* . 34 Individual fits images
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Source name
17- 25 F9.5 deg RAdeg Right Ascension of center (J2000)
26- 34 F9.5 deg DEdeg Declination of center (J2000)
36- 38 I3 --- Nx Number of pixels along X-axis
40- 42 I3 --- Ny Number of pixels along Y-axis
44- 46 I3 Kibyte size Size of FITS file
48- 58 A11 --- FileName Name of FITS file, in subdirectory fits
60- 99 A40 --- Title Title of the FITS file
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Acknowledgements:
Javier Piqueras Lopez, piqueraslj(at)cab.inta-csic.es
(End) Javier Piqueras Lopez [CAB INTA-CSIC], Patricia Vannier [CDS] 22-Mar-2016