GRB 080229B

Aquib Moin (Curtin Institute of Radio Astronomy / Australia Telescope
National Facility), Steven Tingay (Curtin Institute of Radio Astronomy),
Chris Phillips (Australia Telescope National Facility), Gregory Taylor
(University of New Mexico), Mark Wieringa (Australia Telescope National
Facility) and Ralph Martin (Perth Observatory) report:

We observed the SWIFT-XRT X-ray afterglow position of the GRB 080229b
(GCN 7354
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 ) at 4.8 and 8.456 GHz with the Australia Telescope Compact
Array (ATCA) on May 31, 2008 between 04:39:45 UT and 12:09:05 UT.

We did not detect a radio source at the XRT position of the GRB 080229b
afterglow (GCN 7354
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 ). The radio flux density at the GRB X-ray afterglow
position is -0.704 +/- 0.422 mJy at 4.8 GHz, and -0.012 +/- 0.255 mJy at
8.6 GHz (1-sigma).

The Australia Telescope Compact Array (/ Parkes telescope / Mopra
telescope / Long Baseline Array) is part of the Australia Telescope
which is funded by the Commonwealth of Australia for operation as a
National Facility managed by CSIRO.

See field image at:

http://astronomy.ivec.org/dokuwiki/doku.php/grb/grb_080229b_field_image

M. De Pasquale (MSSL/UCL) and J. K. Cannizzo (NASA/UMBC) report
on behalf of the Swift-UVOT team:

The Swift/UVOT observed the field of 080229B, detected by
SuperAgile (Evangelista et al. GCN CIRC 7340
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 ), starting 76.3 Ks
after the trigger. Exposures were taken in the v band.
No optical afterglow is detected at the position of the refined
XRT position (Moretti et al. GCN CIRC 7354
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 ) in the first 5
summed exposures.

  The following 3-sigma upper limit (in the UVOT photometric
system, Breeveld et al., GCN Circ. 6614
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 ) was determined at the
XRT position (RA=13:17:00.4 DEC= -64:51:44.6 J2000):

  Filter  Tstart(Ks)  Tstop(Ks)  Exp(s)   Mag

    v        76.27     104.73     816    >19.8


  We note that this field is very crowded and it suffers from a
high Galactic reddening E(B-V) = 1.9.

A. Moretti (INAF-OAB), J. Mao (INAF-OAB), C. Guidorzi
(Univ. Bicocca & INAF-OAB) report on behalf of the Swift-XRT team:

We have analysed the Swift-XRT observation of GRB 080229B detected by
SuperAgile (Evangelista et al. GCN Circ).  The data consist of 13.4 ks
in Photon Counting (PC) mode starting 27 hours after the SuperAGILE
trigger and ending at 48 hours.

We found a fading, uncatalogued X-ray source at the position: RA:199.25169
Dec:-64.86239 which is equivalent to:

   RA(J2000)  = 13h 17m 00.40s
   Dec(J2000) = -64d 51' 44.6"

with an uncertainty of 3.9 arcseconds (radius, 90% containment). This
location is 73 arcseconds from the SuperAGILE position.

The afterglow is decaying with a power-law slope of 0.9+/-0.5.  

The spectral parameters are poorly constrained due to the paucity of
the statistics (~100 photons).  The spectrum can be modelled with a
power-law of photon index Gamma = 2.8 +/- 1.0, with an absorbing
column of NH = (1.4 +/- 0.7)e22 cm^-2 (consistent with the
Galactic value of 8.9e21 cm^-2).

If the light-curve continues to decay with a slope of 0.9, the
afterglow at 3 days (March 4th) will have an expected count rate of
0.0085 count s-1. This corresponds to an observed (unabsorbed)
flux of 5.8E-13 (2.2e-12) ergs cm-2 s-1.

This circular is an official product of the Swift-XRT team.

Y. Evangelista, E. Del Monte, M. Feroci, E. Costa, I. Donnarumma, 
I. Lapshov, F. Lazzarotto, L. Pacciani, M. Rapisarda, P. Soffitta
(INAF/IASF Rome), A. Giuliani, S. Vercellone, A. Chen, S. Mereghetti, A. 
Pellizzoni, F. Perotti, F. Fornari, M. Fiorini, P. Caraveo, 
A. Zambra (INAF/IASF Milan), A. Bulgarelli, F. Gianotti, 
M. Trifoglio, G. Di Cocco, C. Labanti, F. Fuschino, M. Marisaldi, 
M. Galli, (INAF/IASF Bologna), M. Tavani, G. Pucella, F. D'Ammando, V. 
Vittorini, A. Argan, A. Trois (INAF/IASF Rome), G. Barbiellini, 
F. Longo (INFN Trieste), P. Picozza, A. Morselli (INFN Roma-2),  
M. Prest, E. Vallazza (Universita` dell'Insubria), P. Lipari, 
D. Zanello (INFN Roma-1), and  P. Giommi, C. Pittori, L. A. Antonelli 
(ASDC) and L. Salotti (ASI), on bhealf of the AGILE Team, report:

"SuperAGILE detected and localized a gamma ray burst 
on February 29th, at 23:33:01 UT. The event was approximately 
13 degrees off-axis. The observed duration in the 20-60 keV
energy range is above 100 seconds, with time structure.
The burst was triggered and localized during on ground data processing.  
The burst position was reconstructed as (RA, Dec) (199.221 deg, 
-64.878 deg), which is:

RA(J2000) = 13h 16m 53.13s
Dec(J2000) = -64d 52' 40.8"

with an uncertainty of 3' radius. The given uncertainty accounts 
for both the statistical and systematic errors. 

An analysis of the AGILE Gamma Ray Imager (GRID) data is in progress."

This message may be cited.