J/A+A/562/A70 Imaging GRB 980425 in millimetric and submm (Michalowski+, 2014)
Spatially-resolved dust properties of the GRB 980425 host galaxy.
Michalowski M.J., Hunt L.K., Palazzi E., Savaglio S., Gentile G.,
Rasmussen J., Baes M., Basa S., Bianchi S., Berta S., Burlon D.,
Castro Ceron J.M., Covino S., Cuby J.-G., D'Elia V., Ferrero P., Gotz D.,
Hjorth J., Koprowski M. P., Le Borgne D., Le Floc'h E., Malesani D.,
Murphy T., Pian E., Piranomonte S., Rossi A., Sollerman J., Tanvir N.R.,
de Ugarte Postigo A., Watson D., van der Werf P., Vergani S.D., Xu D.
<Astron. Astrophys. 562, A70 (2014)>
=2014A&A...562A..70M 2014A&A...562A..70M
ADC_Keywords: Gamma rays ; Radio sources ; Photometry, millimetric/submm ;
Ultraviolet
Keywords: dust, extinction - galaxies: individual: ESO 184-G82 -
galaxies: star formation - submillimeter: galaxies -
gamma-ray burst: individual: 980425 - galaxies: ISM
Abstract:
Gamma-ray bursts (GRBs) have been proposed as a tool to study star
formation in the Universe, so it is crucial to investigate whether
their host galaxies and immediate environments are in any way special
compared with other star-forming galaxies. Here we present spatially
resolved maps of dust emission of the host galaxy of the closest known
GRB 980425 at z=0.0085 using our new high-resolution observations from
Herschel, APEX, ALMA and ATCA. We modeled the spectral energy
distributions of the host and of the star-forming region displaying
the Wolf-Rayet signatures in the spectrum (WR region), located 800pc
away from the GRB position. The host is characterised by low dust
content and high fraction of UV-visible star-formation, similar to
other dwarf galaxies. Such galaxies are abundant in the local
universe, so it is not surprising to find a GRB in one of them,
assuming the correspondence between the GRB rate and star-formation.
The WR region contributes substantially to the host emission at the
far-infrared, millimeter and radio wavelengths and we propose this to
be a consequence of its high gas density. If dense environments are
also found close to the positions of other GRBs, then the ISM density
should also be considered as an important factor influencing whether a
given stellar population can produce a GRB, in a similar way as
metallicity.
Description:
Images of the GRB 980425 host presented on Figure 1.
Objects:
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RA (2000) DE Designation(s)
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19 34 54 -52 49.9 GRB 980425 = GRB 980425
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File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 94 19 List of FITS images
img/* . 19 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- 9 F9.5 deg RAdeg Right Ascension of center (J2000)
10- 18 F9.5 deg DEdeg Declination of center (J2000)
20- 23 F4.2 arcsec/pix Scale Scale of the image
25- 28 I4 pix Nx Number of pixels along X-axis
29 A1 --- --- [x]
30- 33 I4 pix Ny Number of pixels along Y-axis
34 A1 --- --- [x]
35 I1 --- Nz ? Number of images
37- 42 E6.3 um lambda Observation wavelength λobs
44- 56 A13 --- FileName Name of FITS file in subdirectory img
58- 83 A26 --- Title Title of the file
85- 94 A10 --- Com Additional comments (frequency)
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Acknowledgements:
Michal Michalowski, klapsztas(at)gmail.com
(End) M. Michalowski [IfA, Edinburgh, UK], P. Vannier [CDS] 10-Dec-2013