GRB 061122
GCN Circular 5836
Subject
INTEGRAL results on GRB 061122
Date
2006-11-22T10:32:30Z (19 years ago)
From
Sandro Mereghetti at IASF/CNR <sandro@iasf-milano.inaf.it>
S.Mereghetti (IASF-Milano), D.Gotz (CEA-Saclay) on behalf of the IBAS
Localization Team report:
Analysis of the INTEGRAL/IBIS data of GRB 061122 (GCN 5834) indicates
that the peak flux in the 20-200 keV range is larger than 11 ph/cmq/s (1-s
integration time) and the fluence over the same energy range is larger
than 3x10e-6 erg/cmq.
This message can be cited.
GCN Circular 5841
Subject
Konus-Wind observation of GRB 061122
Date
2006-11-22T20:15:22Z (19 years ago)
From
Valentin Pal'shin at Ioffe Inst <val@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, and
T. Cline on behalf of the Konus-Wind team report:
The long bright GRB 061122 (Mereghetti et al., GCN 5834, 5836)
triggered Konus-Wind at 28608.132 s UT (07:56:48.132).
As observed by Konus-Wind it had a duration of ~10 s,
fluence 2.31(-0.12, +0.05)x10^-5 erg/cm2,
the 64-ms peak flux measured from T0+3.104 s
8.81(-1.05, +0.83)x10^-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).
The time-integrated spectrum of the GRB
(from T0 to T0+12.032 s) is well fitted (in the 20 keV - 2 MeV range)
by a power law with exponential cutoff model:
dN/dE ~ E^(-alpha) * exp(-(2-alpha)*E/Ep)
with alpha = 1.03 (-0.07, +0.06)
and Ep = 160 (-7, +8) keV (chi2 = 64/62 dof).
The fitting by GRBM (band) model yields only an upper limit on
high energy photon index: beta < -3.31.
All the quoted errors are at the 90% confidence level.
The Konus-Wind light curve of this GRB is available
at http://www.ioffe.rssi.ru/LEA/GRBs/GRB061122_T28608/
GCN Circular 5842
Subject
GRB061122: Swift-XRT position
Date
2006-11-22T21:00:24Z (19 years ago)
From
Andy Beardmore at U Leicester <apb@star.le.ac.uk>
A. P. Beardmore, P. A. Evans, K. L. Page (U Leicester),
S. McBreen (MPE) and D. N. Burrows (PSU) report on behalf of
the Swift-XRT team:
The Swift-XRT began observing the field containing the INTEGRAL
burst GRB 061122 (Mereghetti et al., GCN 5834) at 2006-11-22 14:44:38 UT,
24.47 ks after the trigger. In two orbits of Photon Counting mode data
totalling 2.35 ks we detect an uncatalogued source at
RA(J2000) = 20h 15m 19.80s
Dec(J2000) = +15d 31' 03.0"
with an uncertainty of 4.0 arcsec (90% containment, using the updated
boresight file described by Burrows et al. in GCN Circ. 5750). This is
19.8 arcsec from the initial position reported in GCN 5834, and
within the error circle.
The source is presently at an XRT count rate of 0.065 count/s, but at this
stage of the observation it is impossible to say if it is fading.
This circular is an official product of the Swift-XRT team.
[GCN OPS NOTE(28nov06): Per author's request, the "14:44" was changed to "14:44:38"
and the "24.67 ks" was changed to "24.47 ks".]
GCN Circular 5846
Subject
GRB061122: Swift/UVOT Optical Observations
Date
2006-11-23T13:41:05Z (19 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (UCL-MSSL) & S. McBreen (MPE) report on behalf of the
Swift UVOT team.
The Swift/UVOT began observing the field of GRB 061122 at 14:47:46 UT
on November 22, 2006, around ~7 hours after the INTEGRAL trigger
(Mereghetti et al., GCN 5831). We do not find any source in the
co-added UVOT
observations within the error circle of the XRT (Beardmore et al., GCN
5842).
Following are the 3-sigma magnitude upper limits:
Filter T_start T_end Exposure 3 sigma UL
-------------------------------------------
V 24658 58558 2645 20.69
B 25401 42918 936 20.62
U 25215 42901 1013 20.2
UVW1 25029 59414 1770 19.46
UVM2 24844 58920 2578 20.96
UVW2 24472 58124 2648 21.54
-------------------------------------------
T_start and T_stop are calculated from the time of the burst. The upper
limits are not corrected for Galactic extinction E(B-V) = 0.183 mag.
GCN Circular 5849
Subject
GRB 061122: Candidate Optical Afterglow
Date
2006-11-24T05:00:33Z (19 years ago)
From
Jules Halpern at Columbia U. <jules@astro.columbia.edu>
J. P. Halpern & E. Armstrong (Columbia U.) report on behalf of the
MDM Observatory GRB follow-up team:
"We obtained R-band observations of the field of INTEGRAL GRB 061122
(Mereghetti et al., GCN 5834) on two consecutive nights using the
MDM 2.4m telescope. Within 1" of the Swift XRT candidate X-ray
afterglow (Beardmore et al., GCN 5842), we find a fading object at
(J2000) R.A.=20h15m19.84s, Decl.=+15d31'02.5"
with positional uncertainty ~0.5", and the following magnitudes:
------------------------------------------------
Date(UT) Mid-time(UT) t-t0(hr) R(mag) +/-
------------------------------------------------
Nov. 23 01:52 17.9 22.61 0.05
Nov. 24 02:26 42.5 23.41 0.15
------------------------------------------------
We propose this as the optical afterglow of GRB 061122.
Magnitudes are referenced to the USNO B1.0 star at
(J2000) R.A.=20h15m18.48s, Decl.= +15d31'05.5" with R=17.61,
and are not corrected for Galactic extinction, A_R=0.49 mag
in this direction (Schlegel et al. 1998).
MDM images of the field are posted at
http://www.astro.columbia.edu/~jules/grb/061122/
This message may be cited."
GCN Circular 5852
Subject
GRB 061122: Confirmation of X-ray/Optical Afterglow
Date
2006-11-24T23:20:51Z (19 years ago)
From
Jules Halpern at Columbia U. <jules@astro.columbia.edu>
In follow-up Swift XRT observations of INTEGRAL GRB 061122
(Mereghetti et al., GCN 5834,5836) the X-ray source reported
by Beardmore et al. (GCN 5842) as having 0.065 counts/s at 7 hr
after the burst, has faded to 0.0047 counts/s averaged over the
interval 18-55 hr post burst. Therefore, I regard this as
confirmation of the X-ray afterglow as well as the coincident
optical afterglow reported in GCN 5849.
GCN Circular 5879
Subject
GRB 061122: GETS observation
Date
2006-11-30T10:10:08Z (19 years ago)
From
Kenzo Kinugasa at Gunma Astro. Obs/Japan <kinugasa@astron.pref.gunma.jp>
K. Kinugasa (Gunma Astronomical Observatory) and K. Torii (Osaka U.) report:
The error region of INTEGRAL GRB 061122 (Mereghetti et al. GCN 5834) was
imaged by the robotic 0.25m GETS telescope in the Gunma Astronomical
Observatory. Unfiltered imaging started at 08:46:33 UT (49.1 minutes
after the trigger) after the end of twilight.
We did not detect the optical afterglow (Halpern et al. GCN 5849) and
the following 3-sigma upper limits are derived relative to USNO-A2.0 R mag.
------------------------------------------
StartUT EndUT Limit Exposure
------------------------------------------
08:46:33 09:01:33 >15.5 30s x 20
------------------------------------------