[vsnet-grb-info 1846] GRB050709: Second Epoch Chandra Observation

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  3686
SUBJECT: GRB050709: Second Epoch Chandra Observation
DATE:    05/07/27 01:26:13 GMT
FROM:    Angelo Antonelli at Obs. Astro. di Roma  <a.antonelli at mporzio.astro.it>

L.A. Antonelli, M.L. Conciatore (INAF/OAR), D. Malesani (SISSA), S. 
Covino, P. D'Avanzo, S. Campana, G. Tagliaferri (INAF/OABr), M. Della 
Valle (INAF/OAA), F. Fiore, G.L. Israel, L. Stella (INAF/OAR), G. 
Chincarini (Univ. Milano-Bicocca), report on behalf of the MISTICI 
collaboration:

The Chandra X-ray observatory observed a second time the field of the 
GRB 050709 (Butler et al., GCN 3570; Boer et al., GCN 3653). The 
observation, performed with ACIS, started on 2005 Jul 25.86234 UT and 
ended on 2005 Jul 26.09042, for a total exposure time of 18284 s. The 
X-ray source reported by Fox et al. (GCN 3585) and coincident with the 
proposed optical counterpart (Jensen et al., GCN 3589; Price et al., 
GCN 3612) is still marginally detected in the second epoch.

We obtained for this source a count rate of (8.4+/-3.5)E-4 cts/s in the 
(0.3-8.0 keV) band.
This count rate compared to the one obtained in the previous 
observation in the same band (1.2+/-0.2)E-3 cts/s (Fox et al., GCN 
3585) does not allow us to firmly establish any variability for the 
proposed X-ray afterglow.

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