GRB 071025A
GCN Circular 6989
Subject
GRB 071025a: PAIRITEL observations
Date
2007-10-25T05:07:57Z (18 years ago)
From
Josh Bloom at UC Berkeley <jbloom@astron.berkeley.edu>
J. S. Bloom (UC Berkeley) reports on behalf of a larger collaboration:
"Under autonomous operations, we started observing the position of
GRB 071025a (Pagani et al. GCN 6986) with PAIRITEL at 04:11:08 UT
(about 58s after receiving the trigger). In a mosaic of data
obtained between 2007-10-25 04:12:28 to 2007-10-25 04:21:23 UT, we
confirm the existence of a bright new source (Rykoff et al. GCN 6987;
Covino et al. GCN 6988) at position:
23:40:17.078 +31:46:42.87 (J2000)
with an uncertainty of 250 mas in both axes (relative to 2MASS). A
preliminary magnitude is J = 14.948 +/- 0.022. More observations and
analysis are ongoing."
A finder of the field may be obtained at:
http://lyra.berkeley.edu/~jbloom/grb071025a.ps.gz
The message may be cited.
GCN Circular 7002
Subject
GRB 071025A: Complex Early-Time IR Behavior, Simultaneous with Gamma- and X-rays
Date
2007-10-25T20:40:25Z (18 years ago)
From
Josh Bloom at UC Berkeley <jbloom@astron.berkeley.edu>
J. S. Bloom, N. R. Butler, D. A. Perley, D. L. Starr, R. Foley (UC
Berkeley) report:
"We obtained simultaneous J, H, and Ks band images with fine time
sampling (7.8s cadence) of the afterglow (Rykoff et al. 6987; Covino
et al. 6988) of GRB 070125A (Pagani et al. 6986) with PAIRITEL (*)
beginning ~200s after the BAT trigger. The beginning of the
observations coincides with the fading tale of the prompt emission.
The IR light curve initially rises, then exhibits two prominent peaks
(at T+~500s and T+~1500s) before fading as a powerlaw t^{-1.5+/-0.1},
after t ~ 2000s. A refined data reduction and a search for potential
color variations are in progress."
This message may be cited.
(*) http://pairitel.org
*****************************************************
Joshua Bloom
Assistant Professor, UC Berkeley
601 Campbell Hall, Berkeley, CA 94720
(510) 643-3839 [Office] 447 Campbell
(510) 643-4621 [Lab] 260 Evans
http://astro.berkeley.edu/~jbloom
*****************************************************
GCN Circular 7008
Subject
GRB 071025A: RAPTOR Observations of Complex Early Optical Behavior
Date
2007-10-26T22:22:52Z (18 years ago)
From
James Wren at LANL <jwren@nis.lanl.gov>
J. Wren, W.T. Vestrand, P.R. Wozniak, R. White, H. Davis
of Los Alamos National Laboratory report:
Our Raptor telescopes responded to Swift trigger 295301
(Pagani et al., GCN 6986) at 04:10:14.0 UT, 80.3 seconds
after the trigger and 4.2 seconds after receiving the
GCN packet. We detect faint optical emission from the
counterpart reported by the ROTSE team (Rykoff et al., GCN
6987 and Covino et al., GCN 6988). We observe the first
optical peak reported by Rykoff et al. (GCN 6992) at T+~600s.
The counterpart then fades until T+~1200s. The optical
lightcurve then rebrightens to a peak near T+~1400s at about
the level of the previous peak. This "twin peaks" behavior
seems to be consistent with the IR behavior reported by
Bloom et al. (GCN 7002).