GRB 070612A
GCN Circular 6714
Subject
GRB070612A: Radio upper limit from GMRT
Date
2007-08-07T05:39:00Z (18 years ago)
From
Dipankar Bhattacharya at IUCAA <dipankar@iucaa.ernet.in>
Sabyasachi Pal, C.H. Ishwara-Chandra, Dipankar Bhattacharya and
Atish P. Kamble report on behalf of a larger collaboration:
We observed the field of GRB 070612A (Grupe et al, GCN 6509) at
1280 MHz, using the Giant Meterwave Radio Telescope, from
MJD 54305.08 to 54305.26 (UT 2007 Jul24 01:55:21 to 06:12:36).
This interval corresponds to 41.97-42.15 days after the burst.
The afterglow was not detected. The formal flux density at the
position of the optical afterglow (Cenko et al, GCN 6525)
was 109 +/- 64 micro Jy (1-sigma).
We thank the GMRT staff who made this observation possible.
GMRT is run by the National Centre for Radio Astrophysics of
the Tata Institute of Fundamental Research.
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GCN Circular 6600
Subject
VLA detection of GRB 070612A in C Band
Date
2007-07-05T21:49:36Z (18 years ago)
From
Poonam Chandra at U Virginia/NRAO <pc8s@virginia.edu>
Poonam Chandra (NRAO/UVA) and Dale A. Frail (NRAO) report on behalf of
the Caltech-NRAO-Carnegie GRB Collaboration:
"We used the Very Large Array to observe the field of view toward GRB
070612A (GCN 6509) at a frequency of 4.88 GHz on 2007 June 30th at
20.66 UT. We detect the GRB afterglow at P60 optical afterglow position
(GCN 6517). The flux density of the GRB is 189+/-56 uJy.
The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."
GCN Circular 6583
Subject
GRB 070612A: Allen Telescope Array Observations
Date
2007-06-27T23:06:44Z (18 years ago)
From
Josh Bloom at UC Berkeley <jbloom@astron.berkeley.edu>
R. Forster, M. Wright, J. Hare, J. S. Bloom, G. C. Bower (UC
Berkeley) report on behalf of a large collaboration:
"Using the Allen Telescope Array (ATA, http://ral.berkeley.edu/ata/),
we observed GRB 070612A (Grupe et al., GCN 6509) at 1.4 GHz on 2007
June 16 UT and at 5 GHz on 2007 June 17 UT. The observations made use
of 8 antennas outfitted with dual-polarization receivers. At the
location of the optical afterglow (Updike et al., GCN 6515), we
obtained 3-sigma limits of 50 mJy at 1.4 GHz and 10 mJy at 5 GHz for
the flux density of GRB 070612A at these epochs. The data were
calibrated versus the QSS 0927+392. At L-band the 8 brightest NVSS
were measured to be located within 10% of the synthesized beamwidth
and 100 mJy of the NVSS flux densities. The limits reported herein
are consistent with the tentative WSRT detection at 4.9 GHz (Horst et
al. GCNs 6549