GRB 080613A
GCN Circular 7880
Subject
GRB 080613A: GROND Confirmation of the Afterglow Candidate
Date
2008-06-14T02:28:48Z (17 years ago)
From
Christian Clemens at MPE <cclemens@mpe.mpg.de>
C. Clemens, A. Updike (Clemson University), T. Kruehler, J. Greiner, A. Kupcu
Yoldas, A. Yoldas (all MPE Garching) and G. Szokoly (Eoetvoes Univ., Budapest
and MPE Garching) report on behalf of the GROND team:
We observed the field of GRB 080613A (INTEGRAL trigger 5288; Gotz et al., GCN
#7871) simultaneously in g'r'i'z'JHK with GROND (Greiner et al. 2008, PASP
120, 405) mounted at the 2.2m ESO/MPI telescope at La Silla Observatory
(Chile).
Observations started at 00:25 UT on June 14th, 2008, 14.8 hrs after the GRB
trigger with 25 mins of effective exposures in g'r'i'z' and 20 mins in JHK.
We do not detect any object at the position reported by Guidorzi et al., GCN
#7872) to the following 3-sigma upper limits:
g' > 24.2,
r' > 23.9,
i' > 23.5,
z' > 23.4,
J > 22.3 and
H > 21.3.
Given upper limits are calibrated against SDSS as well as 2MASS field stars.
This indicates a clear fading of the source. We therefore confirm this to be
the afterglow of GRB 080613A.
GCN Circular 7881
Subject
GRB080613A: Swift/UVOT Upper Limits
Date
2008-06-14T02:43:26Z (17 years ago)
From
Erik Hoversten at Swift/Penn State <hoversten@astro.psu.edu>
E. A. Hoversten (PSU) and S. T. Holland (CRESST/USRA/GSFC) on behalf
of the Swift/UVOT team.
The Swift Ultra-Violet/Optical Telescope (UVOT) began settled
observations of the INTEGRAL-detected GRB 080613A (Gotz, et al., GCN
Circ. 7871) 6.7 hours after the trigger. No afterglow is detected at the
position of the R-band detection by the Faulkes Telescope North
(Guidorzi, et al., GCN Circ. 7872). The 22.2 magnitude upper limit in
the white band suggests the R~19 object seen by Guidorzi, et al. 3.9
minutes after the trigger has faded and is indeed the afterglow.
Filter T_start(s) T_stop(s) Exp(s) Mag UL (3sig)
white 24725 25189 456 >22.2
v 25195 25638 436 >20.5
b 24257 24720 456 >21.5
The values quoted above are in the UVOT photometric system (Poole et al.
2008, MNRAS, 383, 627). They are not corrected for the expected
Galactic extinction corresponding to a reddening of E(B-V)=0.023 mag in
the direction of the burst (Schlegel et al. 1998).
GCN Circular 7882
Subject
GRB 080613A: Swift-XRT detection of the afterglow
Date
2008-06-14T09:15:27Z (17 years ago)
From
Cristiano Guidorzi at INAF-OAB <cristiano.guidorzi@brera.inaf.it>
C. Guidorzi (INAF-OAB) and C. B. Markwardt (CRESST/GSFC/UMD) report
on behalf of the Swift-XRT team:
The Swift XRT began observing the INTEGRAL GRB 080613A
(Gotz et al., GCN Circ 7871) on June 13, 16:19 UT, 24.2 ks after
the INTEGRAL trigger. The data consist of 3.6 ks observed in Photon
Counting
mode.
We detect a single X-ray source within the INTEGRAL error circle at the
position
RA, Dec = 213.27213, +5.17256 which is equivalent to:
RA (J2000): 14 13 05.31
Dec (J2000): +05 10 21.2
with an uncertainty of 5.2 arcsec (radius, 90% confidence).
This position lies 4.9" from the optical afterglow found with the
Faulkes Telescope North
(Guidorzi et al., GCN Circ. 7872) and later confirmed by GROND (Clemens
et al. GCN Circ. 7880)
and Swift-UVOT (Hoversten and Holland, GCN Circ. 7881), and is
therefore consistent with being the X-ray afterglow of GRB 080613A.
Presently there is marginal evidence for fading: a power-law fit of the
light curve
gives a decay index of 1.2 � 1.5, so still compatible with a constant
rate of
of (2.8 � 0.3)e-2 counts/s.
Forced by the small number of counts, we extracted the 0.3-10 keV spectrum
from a 10-pixel radius circular region and adopted the Cash statistics.
The spectrum can be fit with a power law with an absorbing column
density fixed to the Galactic value (2.0e20 cm-2) and a photon index of
1.3 � 0.3. The observed (unabsorbed) 0.3-10 keV flux
is 1.50 (1.53)e-12 erg cm-2 s-1.
This circular is an official product of the Swift-XRT team.
GCN Circular 7885
Subject
GRB080613A: Optical upper limits with Okayama MITSuME telescope
Date
2008-06-17T23:26:42Z (17 years ago)
From
Michitoshi Yoshida at Okayama Astrophysical Obs <yoshida@oao.nao.ac.jp>
M. Yoshida, K. Yanagisawa, Kuroda, D., Y. Shimizu, S. Nagayama,
Toda, H. (OAO, NAOJ) and N. Kawai (Tokyo Tech) report on behalf
of the MITSuME collaboration:
We performed optical imaging observation (g', Rc, and Ic) of the
field of GRB 080613A (Gotz et al. GCN 7871) with 50cm MITSuME
telescope at Okayama Astrophysical Observatory from 13:44:35 UT
(4h 9m after the trigger) to UT 15:13:05 on June 13 2008.
We found no new source within a 10 arcsec radius of the position
of the optical afterglow candidate reported by Guidorzi et al.
(GCN 7872). Three sigma limiting magnitudes of our observation
are listed below.
Start-UT mid-UT exp-T g' Rc Ic
--------------------------------------------------------------
2008-06-13 13:44:35 14:28:50 77min >18.4 >17.7 >16.7
--------------------------------------------------------------
GCN Circular 7888
Subject
VLA upper limit on INTEGRAL burst GRB 080613A
Date
2008-06-20T13:13:45Z (17 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
080613A (GCN 7871) at a frequency of 8.46 GHz on 2008 June 16.17 UT.
The GRB radio afterglow is undetected and the peak radio flux at the
XRT afterglow position (GCN 7882) is 7 � 45 uJy.
The National Radio Astronomy Observatory is a facility of the National
Science Foundation operated under cooperative agreement by Associated
Universities, Inc."