GRB 060211A
GCN Circular 5204
Subject
GRB 060211A : WIDGET simultaneous optical observations
Date
2006-06-03T12:40:27Z (20 years ago)
From
Toru Tamagawa at RIKEN <tamagawa@riken.jp>
Y. Urata (Saitama-U), M. Kuwahara (TUS/RIKEN), M. Tashiro, K. Abe,
K. Onda, N. Kodaka, K. Masuno (Saitama-U), F. Usui (ISAS/JAXA),
T. Tamagawa (RIKEN) report:
"WIDGET has continuously monitored the entire error region of the GRB
060211A (Hurkett et al. GCN 4736, 4740) with repeat of unfiltered
5-second exposures during the night of 11th February. The 1-sigma
limiting magnitude of images taken between 792 seconds before and 321
seconds after the burst was around V=10.8 magnitude. The magnitude was
derived by the Tycho-2 catalog. There was no significant emission from
the X-ray afterglow position up to the limiting magnitudes."
This message maybe cited.
GCN Circular 4927
Subject
GRB 060211A: optical observation
Date
2006-03-27T12:11:35Z (20 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
D. Sharapov (MAO, and NOT, La Palma), M. Ibrahimov, (MAO), A. Pozanenko
(IKI) and V. Rumyantsev (CrAO) on behalf of larger GRB follow up
collaboration report:
We observed the refined XRT error box reported by Hurkett et al. (GCN 4740)
of GRB 060211A (Hurkett et al. GCN 4736; Krimm et al. GCN 4757) with 1.5m
telescope of Maidanak Astronomical Observatory in R-band on Feb. 11 (UT)
15:02 - 15:22. The limiting magnitude is based on USNO B1.0:
Mid. time, Exp., Limit, Seeing
(UT) (s)
Feb.11.640 1860 22.0 ~1.5"
The extended object in the FOV with coordinates RA(J2000)= 03:53:31 (+/-
10 arcsec) Dec(J2000)= +21:28:58 (+/- 10 arcsec) with R~21.5 is the
asteroid 16306 moving toward N-E.
The combined image can be found in
http://grb.rssi.ru/GRB060211/GRB060211_AZT22R.jpg
GCN Circular 4760
Subject
GRB 060211a: WIRO NIR Observations
Date
2006-02-14T03:32:59Z (20 years ago)
From
Jay Norris at NASA-GSFC/LHEA <jnorris@lheapop.gsfc.nasa.gov>
J. Norris, A. Kutyrev (NASA/GSFC), R. Ganguly, R. Canterna,
and M. Pierce (U. Wyoming) report:
We observed the refined XRT error box reported by Hurkett et al. (GCN 4740)
for the very long burst, GRB 060211a (Swift trigger #181126; Hurkett et al.
GCN 4736; Krimm et al. GCN 4757) with the 2.3-meter WIRO telescope.
Observations commenced at 2006/02/12 02:44 UT (17 hrs after the burst)
and continued until 03:24 UT. We obtained thirty-six 50-s integrations
in the J band under poor seeing conditions. In the stacked image,
no source was detected within the XRT error circle to a limit of
J = 19.1 (3-sigma upper limit).
GCN Circular 4757
Subject
GRB 060211A: Further refined analysis of the Swift burst
Date
2006-02-13T18:39:23Z (20 years ago)
From
Hans Krimm at NASA-GSFC <krimm@milkyway.gsfc.nasa.gov>
H. Krimm (GSFC/USRA), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (GSFC/UMD), C. Hurkett (U Leicester),
C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/ORAU), G. Sato (ISAS), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
Using the data set from T-300 to T+303 sec from a recent telemetry
downlink, we report further analysis of the results from BAT GRB 060211A
(trigger #181126) (Hurkett, et al., GCN 4736, Sato, et all, GCN 4751).
The BAT ground-calculated position is RA,Dec = 58.380, 21.489 deg
{3h 53m 31.1s, 21d 29' 20.0"} (J2000) +- 1.5 arcmin, (radius,
sys+stat, 90% containment). The partial coding was 100%.
The mask-weighted lightcurve shows that this was a very long burst.
There was a weak, soft precursor starting at T-180 secs and lasting,
in the lowest energy band, until T-90 secs. There is another episode
of weak emission from T-10 to T+50, and then two prominent peaks
from T+50 to T+100 and from T+130 to T+180 secs. The first of
the main peaks is harder than the second. There is no significant
emission beyond T+190 secs. T90 (15-350 keV) is (126 +- 5) sec
(estimated error including systematics).
The time-averaged spectrum from T+47.8 to T+191.0 is best fit by
a power law with an exponential cutoff. This fit gives a photon
index of 0.85 +- 0.53, and Epeak of 58.3 +- 13.2 keV (chi squared 59
for 56 d.o.f.). For this model the total fluence in the 15-150 keV band
is (1.5 +- 0.1) x 10^-06 erg/cm2 and the 1-sec peak flux measured
from T+145.58 sec in the 15-150 keV band is (0.4 +- 0.1) ph/cm2/sec.
A fit to a simple power law gives a photon index of 1.76 +- 0.11
(chi squared 70 for 57 d.o.f.). All the quoted errors are at the 90%
confidence level.
GCN Circular 4751
Subject
GRB 060211A: Partial refined analysis on the Swift-BAT burst
Date
2006-02-12T17:06:41Z (20 years ago)
From
Scott Barthelmy at NASA/GSFC <Scott@lheamail.gsfc.nasa.gov>
G. Sato (ISAS), L. Barbier (GSFC), S. Barthelmy (GSFC),
J. Cummings (GSFC/ORAU), E. Fenimore (LANL), N. Gehrels (GSFC),
D. Hullinger (GSFC/UMD), C. Hurkett (U Leicester), H. Krimm (GSFC/USRA),
C. Markwardt (GSFC/UMD), D. Palmer (LANL), A. Parsons (GSFC),
T. Sakamoto (GSFC/ORAU), J. Tueller (GSFC)
on behalf of the Swift-BAT team:
Using a paritally downloaded data set from T-60 to T+123 sec
from a recent telemetry downlink, we report further analysis
of BAT GRB 060211A (trigger #181126) (Hurkett, et al., GCN 4736).
The BAT ground-calculated position is RA,Dec = 58.361,+21.485 deg
{3h 53m 26.6s,+21d 29' 4.4"} (J2000) +- 1.5 arcmin, (radius, sys+stat,
90% containment). The partial coding was 100%.
Using data from T-60 to +123, the lightcurve shows some very weak emission
starting at T_zero out to T+50, then the bulk of the emission is
from T+50 to T+100 with weak emission extending out to T+123
where our downloaded data set currently ends. T90 (15-350 keV) is 43 +- 10 sec
(estimated error including systematics).
The time-averaged spectrum from T+47.8 to T+97.1 is best fit by a power law
with an exponential cutoff. This fit gives a photon index 0.40 +- 0.64,
and an Epeak of 94 +- 49 keV (chi squared 42 for 56 d.o.f.).
For this model the total fluence in the 15-150 keV band is
8.2 +- 0.8 x 10^-07 erg/cm2 and the 1-sec peak flux measured
from T+53.94 sec in the 15-150 keV band is 0.3 +- 0.1 ph/cm2/sec.
A fit to a simple power law gives a photon index of 1.30 +- 0.14
(chi squared 49 for 57 d.o.f.). All the quoted errors are at the 90%
confidence level.
GCN Circular 4740
Subject
GRB 060211A: Swift XRT Team Refined Analysis
Date
2006-02-11T16:58:32Z (20 years ago)
From
Cheryl Pauline Hurkett at Leicester U <cph9@star.le.ac.uk>
C. P. Hurkett, K. Page, E. Rol, J. Osborne, O. Godet and A. Beardmore (U
Leicester) report on behalf of the Swift XRT team:
We have analysed the Swift XRT data from the first orbit observation of
GRB 060211A (Hurkett et al. GCN 4736), with a total Windowed Timing (WT)
mode exposure of 195 seconds and Photon Counting (PC) mode exposure of
1040 seconds. The refined XRT position is:
RA(J2000) = 03 53 32.8
Dec(J2000) = +21 29 21.0
This position is 3.9 arcseconds from the XRT position given in GCN
4736. We estimate an uncertainty of 3.7 arcseconds radius (90%
containment).
The 0.3-10 keV light curve in WT and PC mode starts 185 seconds from the
BAT trigger. The lightcurve (after only one orbit) appears to exhibit a
broken powerlaw behaviour, where both decay indices are steep. The indices
are: alpha_1 = 4.14 +/- 0.11, which at 475 seconds (+48/-32) changes to a
slower decay of alpha_2 = 2.26 (+0.26/-0.32).
A preliminary spectral fit to the WT data gives a power law photon
index of 1.94 +/- 0.07 in the 0.3-10 keV band, where Galactic
absorption is assumed to be 1.25e21 cm^-2. An excess absorption
component is noted at (7+/-2)e20 cm^-2. In the time range of 185-380
seconds after trigger, the estimated unabsorbed 0.3-10 keV flux is
1.19e-9 ergs/cm2/s. The observed 0.3-10.0 keV flux is 8.54e-10
erg/cm2/s.
Because of the Malindi Gap, only one orbit of data has been analysed
so far. We cannot accurately estimate the flux at T+24 hr yet.
This circular is an official product of the Swift XRT Team.