GRB 100906A
GCN Circular 11227
Subject
GRB 100906A: Swift detection of a burst with an optical afterglow
Date
2010-09-06T14:07:13Z (15 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
C. B. Markwardt (NASA/GSFC), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), D. N. Burrows (PSU), V. D'Elia (ASDC),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
J. M. Gelbord (PSU), O. Godet (U Leicester), J. A. Kennea (PSU),
N. P. M. Kuin (UCL-MSSL), W.B Landsman (GSFC),
O. M. Littlejohns (U Leicester), F. E. Marshall (NASA/GSFC),
D. C. Morris (GWU/GSFC), P. T. O'Brien (U Leicester),
K. L. Page (U Leicester), B. Sbarufatti (INAF-OAB/IASFPA),
M. H. Siegel (PSU), R. L. C. Starling (U Leicester) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:
At 13:49:27 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100906A (trigger=433509). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 28.709, +55.614, which is
RA(J2000) = 01h 54m 50s
Dec(J2000) = +55d 36' 50"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows multiple bright peaks
with a duration of about 130 sec. The peak count rate
was ~11000 counts/sec (15-350 keV), at ~10 sec after the trigger.
The XRT began observing the field at 13:50:47.6 UT, 80.2 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 28.68305, 55.62985
which is equivalent to:
RA(J2000) = 01h 54m 43.93s
Dec(J2000) = +55d 37' 47.5"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 78 arcseconds from the BAT onboard position, within the BAT
error circle. This position may be improved as more data are received;
the latest position is available at http://www.swift.ac.uk/sper.
A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density in excess of the Galactic value (2.21 x
10^21 cm^-2, Kalberla et al. 2005), with an excess column of 2.6
(+2.21/-1.90) x 10^21 cm^-2 (90% confidence).
The initial flux in the 0.1 s image was 2.34e-08 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 250 seconds with the U filter starting
146 seconds after the BAT trigger. There is a candidate afterglow in the
rapidly available 2.7'x2.7' sub-image at
RA(J2000) = 01:54:44.11 = 28.68380
DEC(J2000) = +55:37:49.6 = 55.63045
with a 90%-confidence error radius of about 0.61 arc sec. This position is 1.6
arc sec. from the center of the XRT error circle. The estimated magnitude is
14.90 with a 1-sigma error of about 0.14. No correction has been made for the
expected extinction corresponding to E(B-V) of 0.36.
A bright XRT flare at ~120 s corresponds to the last peak in the prompt emission.
The UVOT bright source is probably also associated in time with the flare. More
information to follow.
Burst Advocate for this burst is C. B. Markwardt (Craig.Markwardt AT nasa.gov).
Please contact the BA by email if you require additional information
regarding Swift followup of this burst. In extremely urgent cases, after
trying the Burst Advocate, you can contact the Swift PI by phone (see
Swift TOO web site for information: http://www.swift.psu.edu/too.html.)
GCN Circular 11228
Subject
GRB 100906A: MASTER early OT observations
Date
2010-09-06T14:12:54Z (15 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
K.Ivanov, O.Chuvalaev, V.Poleschuk, E.Konstantinov, V.Lenok, O.Gres,
S.Yazev, N.M.Budnev,
Irkutsk State University
E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina,
D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov,
D.Zimnukhov, M. Kornilov
Sternberg Astronomical Institute, Moscow State University
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik
Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk
V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov
Ural State University, Kourovka
Two MASTER robotic telescopes (MASTER-Net: http://observ.pereplet.ru)
located near Baykal Lake (Tunka) and Blagoveschensk was pointed to the
Swift GRB 100906A (Markwardt et al., GCN CIRCULAR
11227) 23 sec after Notice
time (38 s after trigger time) and 43 s after Notice time (58s after
trigger time).
We have a number polarization, unfiltered images with exposition
10, 20, 30, 40, 60... s.
We see bright OT at Swift Uvot position (Markwardt et al., GCN CIRCULAR
11227).
The message may be cited.
mailto: lipunov@sai.msu.ru
GCN Circular 11229
Subject
GRB 100906A : Faulkes Telescope North optical observations
Date
2010-09-06T14:30:42Z (15 years ago)
From
Andrea Melandri at Liverpool John Moores U <axm@astro.livjm.ac.uk>
A. Melandri (INAF-OAB), D. Kopac (U. Ljubljana) and Z. Cano (LJMU)
report on behalf of a large collaboration:
The Faulkes Telescope North automatically began observing Swift
GRB 100906A (trigger = 433509, Markwardt et al., GCN 11227) on
September 06,13:53:03 UT, about 3.5 minutes from the GRB trigger time.
We clearly identify an uncatalogued object at the following position:
RA(J2000.0): 01:54:44.09
Dec(J2000.0): +55:37:49.5
The position is consistent with UVOT candidate and the object is
clearly fading.
Preliminary photometry gives a magnitude of R=15.5 +/- 0.1 @800 s
after the
burst event.
Observations are going on.
GCN Circular 11230
Subject
GRB 100906A: Gemini-N/GMOS redshift
Date
2010-09-06T15:15:39Z (15 years ago)
From
Nial Tanvir at U.Leicester <nrt3@star.le.ac.uk>
N. R. Tanvir, K. Wiersema (U. Leicester) and A. J. Levan (U. Warwick)
report on behalf of a larger collaboration:
We observed the location of GRB 100906A (Markwardt et al. GCN 11227;
Ivanov et al. GCN 11228; Melandri et al. GCN 11229) with
the Gemini-North Telescope on Mauna Kea using the GMOS spectrograph.
Observations began at 14:30 UT, approximately 40 minutes post burst.
We detect strong continuum from the afterglow, and identify numerous
absorption lines, including CIV (1458, 1551A), FeII (2344, 2374, 2383A)
at a common redshift of z=1.727.
Further analysis is ongoing.
We acknowledge the support of Chad Trujillo in obtaining these observations.
GCN Circular 11231
Subject
GRB 100906A: MASTER preliminary polarization prompt light curve
Date
2010-09-06T15:23:17Z (15 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
E. Gorbovskoy, V. Lipunov, V.Kornilov, A.Belinski, N.Shatskiy, N.Tyurina,
D.Kuvshinov, P.Balanutsa, V.V.Chazov, P.V.Kortunov, A.Kuznetsov,
D.Zimnukhov, M. Kornilov
Sternberg Astronomical Institute, Moscow State University
K.Ivanov, O.Chuvalaev, V.Poleschuk, E.Konstantinov, V.Lenok, O.Gres,
S.Yazev, N.M.Budnev,
Irkutsk State University
V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk
V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov
Ural State University, Kourovka
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik
Kislovodsk Solar Station of the Pulkovo Observatory
Two MASTER robotic telescopes (MASTER-Net: http://observ.pereplet.ru)
located near Baykal Lake (Tunka) and Blagoveschensk was pointed to the
Swift GRB 100906A (Markwardt et al., GCN CIRCULAR
11227) 23 sec after Notice time (38 s after trigger time) and 43 s after
Notice time (58s after trigger time) (Ivanov et al., GCN CIRCULAR 11228).
We see brightening and decay of the prompt optical emission in both
polarizations.
The preliminary light curve is available at
http://observ.pereplet.ru/images/GRB100906A/pre_lc.gif
This automatical phtometry calbrated by USNOB1 stars.
The message may be cited.
mailto: lipunov@sai.msu.ru
GCN Circular 11232
Subject
GRB 100906A: UKIRT zYJHK Observation
Date
2010-09-06T15:27:40Z (15 years ago)
From
Myungshin Im at Seoul Nat U <mim@astro.snu.ac.kr>
Myungshin Im, Changsu Choi, Hyunsung Jun, Eugene Kang (CEOU/Seoul
National University), Y. Urata (NCU), P. Choi (Pomona College),
T. Sakamoto (NASA/GSFC), and N. Gehrels (NASA/GSFC) on behalf
of a larger collaboration
Using UKIRT, we obtained multiple sets of zYJHK images of GRB 100906A
(Markwardt et al. GCN 11227) with a series of z, Y, J, H, and K filters
using UKIRT. The observation started at Sept. 06, 14:23 UT or roughly 34
minutes after the BAT alert.
We clearly identify an uncatalogued source in images in all the filters.
The preliminary magnitude of the afterglow is J= 14.93 +- 0.02 and
K=13.54 +- 0.02 (Vega), calibrated against 2MASS stars in the vicinity.
GCN Circular 11233
Subject
GRB 100906A: Swift-BAT refined analysis
Date
2010-09-06T16:31:20Z (15 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), C. B. Markwardt (GSFC/UMD),
D. M. Palmer (LANL), T. Sakamoto (GSFC/UMBC), M. Stamatikos (OSU),
J. Tueller (GSFC), T. N. Ukwatta (GWU)
(i.e. the Swift-BAT team):
Using the data set from T-61 to T+242 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 100906A (trigger #433509)
(Markwardt, et al., GCN Circ. 11227). The BAT ground-calculated position is
RA, Dec = 28.697, 55.634 deg, which is
RA(J2000) = 01h 54m 47.4s
Dec(J2000) = +55d 38' 03.7"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 46%.
The mask-weighted light curve shows several bright peaks. The first pair
of overlapping peaks starts at ~T-0.2 sec, peaks at ~T+2 and ~T+10 sec,
and almost returns to background at ~T+35 sec. There is a small peak
at ~T+50 sec. Then there are four overlapping peaks from ~T+100 to ~T+118 sec.
T90 (15-350 keV) is 114.4 +- 1.6 sec (estimated error including systematics).
The time-averaged spectrum from T-0.2 to T+130.5 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.78 +- 0.03. The fluence in the 15-150 keV band is 1.2 +- 0.0 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+10.48 sec in the 15-150 keV band
is 10.1 +- 0.4 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/433509/BA/
GCN Circular 11235
Subject
GRB 100906A: MASTER preliminary prompt+afterglow lc
Date
2010-09-06T18:13:03Z (15 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <gcncirc@observ.inetcomm.ru>
D.Kuvshinov, V.Kornilov, E. Gorbovskoy, V. Lipunov, A.Belinski,
N.Shatskiy, N.Tyurina, P.Balanutsa, V.V.Chazov, P.V.Kortunov,
A.Kuznetsov, D.Zimnukhov, M. Kornilov, A.Sankovich
Sternberg Astronomical Institute, Moscow State University
K.Ivanov, O.Chuvalaev, V.Poleschuk, E.Konstantinov, V.Lenok, O.Gres,
S.Yazev, N.M.Budnev,
Irkutsk State University
V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk
V.Krushinski, I.Zalozhnich, T.Kopytova, A. Popov
Ural State University, Kourovka
A. Tlatov, A.V. Parhomenko, D. Dormidontov, V.Sennik
Kislovodsk Solar Station of the Pulkovo Observatory
Observations on MASTER robotic telescope at Tunka (MASTER-Net:
http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy,
vol. 2010, pp. 1-7) are continued (Ivanov et al., GCN CIRCULAR 11228,
Gorbovskoy et al., GCN CIRCULAR 11231).
We have very smoth light curve up to 4 hours after trigger time.
The power low index afterglow decay (F~T_alpha) apha is equal -0.83+-0.02
.
The preliminary 20 min automatical light curve is available at
http://observ.pereplet.ru/images/GRB100906A/lc_GRB100906A_30min.png
(unfiltered).
This automatical pohtometry calibrated by USNOB1 stars.
The message may be cited.
mailto: lipunov@sai.msu.ru
GCN Circular 11238
Subject
GRB 100906A: TLS Multicolor Observations
Date
2010-09-06T20:39:03Z (15 years ago)
From
Alexander Kann at TLS Tautenburg <kann@tls-tautenburg.de>
D. A. Kann, A. Nicuesa Guelbenzu, F. Ludwig and B. Stecklum (TLS
Tautenburg) report:
We observed the afterglow of the bright Swift GRB 100906A (Markwardt et
al., GCN 11227) with the 1.34m TLS Schmidt telescope as soon as dusk set
in. We obtained 3 x 300 sec images in Z, Ic, Rc, V and B each. The
afterglow is clearly detected in all images.
Assuming the star at RA = 01:54:46.82, Dec. = +55:37:55.3 to have
USNOB1.0 R2 = 15.70, we find the following magnitude for the afterglow:
Rc = 18.84 +/- 0.03 at 0.247478 days after the GRB.
Further observations are planned if weather permits.
This message may be cited.
GCN Circular 11239
Subject
GRB 100906A: Ondrejov 65cm observations
Date
2010-09-06T21:41:29Z (15 years ago)
From
Petr Kubanek at AIO <pkubanek@gmail.com>
Kamil Hornoch, Peter Kusnirak, Barbora Mikulecka, Petra Hornochova,
Petr Scheirich, Tomas Kusnirak and Jan Strobl (Astronomical Institute,
Czech Republic) and Petr Kubanek (IPL UV Valencia, IAA CSIC Granada)
reports on behalf of larger collaboration:
We observed position of GRB100906A with Ondrejov 65cm telescope. Its
optical counterpart (Markwardt et al., GCN 11227) is well detected on
stacked 6x180 second R band exposure with mid-point at 2010-09-06
19:51:14 UT, with preliminary magnitude 19.5 +- 0.5 mag.
Further observations and calibrations with this as well as other
instruments are ongoing.
GCN Circular 11240
Subject
GRB100906A: MITSuME Okayama Optical Observation
Date
2010-09-07T00:06:52Z (15 years ago)
From
Daisuke Kuroda at OAO/NAOJ <dikuroda@oao.nao.ac.jp>
D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ),
S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)
and N. Kawai(Tokyo Tech)
report on behalf of the MITSuME collaboration:
We observed the field of GRB 100906A (Markwardt et al., GCN 11227)
with the optical three color (g', Rc and Ic) CCD camera attached
to the MITSuME 50cm telescope of Okayama Astrophysical Observatory.
The observation started on 2010-09-06 13:53:54 UT (~4.4 min after
the burst). We detected the previously reported afterglow
(Markwardt et al., GCN 11227; Ivanov et al., GCN 11228; Melandri
et al., GCN 12229) in all the three bands.
Photometric results of the OT are listed below.
We used GSC2.3 catalog for flux calibration.
#T0+[day] MID-UT T-EXP[sec] g' g'_err Rc Rc_err Ic Ic_err
----------------------------------------------------------------------
0.00662 13:58:60 540.0 15.58 0.04 14.42 0.02 14.00 0.02
0.01784 14:15:09 540.0 16.52 0.05 15.35 0.03 14.98 0.04
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
GCN Circular 11241
Subject
GRB100906A: Errata of MITSuME Okayama about observation time
Date
2010-09-07T01:22:47Z (15 years ago)
From
Daisuke Kuroda at OAO/NAOJ <dikuroda@oao.nao.ac.jp>
D. Kuroda, K. Yanagisawa, Y. Shimizu, H. Toda (OAO, NAOJ),
S. Nagayama (NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)
and N. Kawai(Tokyo Tech)
report on behalf of the MITSuME collaboration:
The observation time in the list reported in GCN 11240 is incorrect.
We made a mistake in calculating the MID-UT.
We revise as follows:
#T0+[day] MID-UT T-EXP[sec] g' g'_err Rc Rc_err Ic Ic_err
----------------------------------------------------------------------
0.00662 13:58:59 540.0 15.58 0.04 14.42 0.02 14.00 0.02
0.01784 14:15:08 540.0 16.52 0.05 15.35 0.03 14.98 0.04
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
GCN Circular 11242
Subject
GRB 100906A: Swift/UVOT Observations
Date
2010-09-07T02:33:56Z (15 years ago)
From
Mike Siegel at PSU/Swift MOC <siegel@astro.psu.edu>
M. H. Siegel (PSU) and C. B. Markwardt (NASA/GSGC) report on behalf
of the Swift/UVOT team.
The Swift/UVOT began settled observations of the field of
GRB 100906A 89s after the BAT trigger (Markwardt et al.,
GCN Circ. 11227). Data summed from the first orbit confirms
a fading optical transient at the position report by Markwardt
et al. The non-detection in the UVW2 and UVM2 filters is consistent
with the Gemini redshift of 1.727 reported by Tanvir et al.
(GCN Circ. 11230). Observations of the GRB are continuing.
The magnitudes and 3-sigma upper limits for the finding chart
(fc) and summed exposures are reported below:
FILTER T_start(s) T_stop Exposure Mag/3UL
========================================================
u (fc) 146 396 245 14.93+-0.02
u 146 1305 490 15.40+-0.01
v 453 1381 116 15.97+-0.05
b 403 1330 116 16.49+-0.04
uvw1 503 1280 97 17.13+-0.11
uvm2 478 1404 115 >18.97
uvw2 429 1356 116 >19.19
=======================================================
The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.36 (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).
GCN Circular 11243
Subject
GRB 100906A: Enhanced Swift-XRT position
Date
2010-09-07T03:20:48Z (15 years ago)
From
Phil Evans at U of Leicester <pae9@star.le.ac.uk>
M.R. Goad, J.P. Osborne, A.P. Beardmore and P.A. Evans (U. Leicester)
report on behalf of the Swift-XRT team.
Using 5488 s of XRT Photon Counting mode data and 7 UVOT
images for GRB 100906A, we find an astrometrically corrected X-ray
position (using the XRT-UVOT alignment and matching UVOT field sources
to the USNO-B1 catalogue): RA, Dec = 28.68397, +55.63068 which is equivalent
to:
RA (J2000): 01h 54m 44.15s
Dec (J2000): +55d 37' 50.5"
with an uncertainty of 1.4 arcsec (radius, 90% confidence).
This position may be improved as more data are received. The latest
position can be viewed at http://www.swift.ac.uk/xrt_positions. Position
enhancement is described by Goad et al. (2007, A&A, 476, 1401) and Evans
et al. (2009, MNRAS, 397, 1177).
This circular was automatically generated, and is an official product of the
Swift-XRT team.
GCN Circular 11244
Subject
GRB 100906A: Swift-XRT refined analysis
Date
2010-09-07T03:58:18Z (15 years ago)
From
Andy Beardmore at U Leicester <apb@star.le.ac.uk>
A. P. Beardmore (U. Leicester) and C. B. Markwardt (NASA/GSFC) report
on behalf of the Swift-XRT team:
We have analysed 16.6 ks of XRT data for GRB 100906A (Markwardt et
al. GCN Circ. 11227), from 70 s to 40.2 ks after the BAT trigger. The
data comprise 228 s in Windowed Timing (WT) mode (the first 9 s were
taken while Swift was slewing) with the remainder in Photon Counting
(PC) mode. The enhanced XRT position for this burst was given by Goad
et al. (GCN. Circ 11243).
The X-ray light curve initially shows a large flare, peaking at a
count rate of ~2000 count s^-1 at T+120s, contemporary with the late
time BAT activity (Barthelmy et al., GCN Circ. 11233). It then
declines rapidly before breaking to a shallower decay slope of alpha =
0.74 +/- 0.04 after T+270s. This is followed by a further break at
T+10854 s to an slope of 1.96 +0.17 -0.13.
A spectrum formed from the PC mode data can be fit by an absorbed
power-law with a photon index of 2.15 +/-0.08. The best-fitting
absorption column is (8.1 +/- 2.5) x 10^21 cm^-2, at a redshift of
1.727 (Tanvir et al. GCN Circ. 11230), in addition to the Galactic
value of 2.2 x 10^21 cm^-2 (Kalberla et al. 2005). The counts to
observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from
this spectrum is 4.1 x 10^-11 (7.1 x 10^-11) erg cm^-2 count^-1. We
do not report a WT time averaged spectral fit here as this would be
affected by the spectral evolution during the flaring activity,
evident in the hardness ratio.
If the light curve continues to decay at the same rate, the count rate
at T+24 hours will be 5.9 x 10^-3 count s^-1, corresponding to an
observed (unabsorbed) 0.3-10 keV flux of 2.4 x 10^-13 (4.2 x 10^-13)
erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00433509.
This circular is an official product of the Swift-XRT team.
GCN Circular 11245
Subject
GRB 100906A: Observations at the Virtual Telescope
Date
2010-09-07T04:25:33Z (15 years ago)
From
Gianluca Masi at Bellatrix Astronomical Obs <gianluca@bellatrixobservatory.org>
G. Masi (Bellatrix Astronomical Observatory, Italy) reports:
The Virtual Telescope main instrument (0.36m-f/8.7) observed
this GRB afterglow on Sept. 7, 2010 at 03:35 Universal Time.
Unfiltered photometry, using R mags from USN0 B1.0 for the
reference stars, provided a magnitude of 19.5, while the
astrometry provided the following end figures:
RA: 44.10s
Decl.: 49.5"
(J2000.0)
in excellent agreement with UVOT finding (GCN 11227)
This message can be cited.
GCN Circular 11247
Subject
GRB 100906A: TLS Monitoring
Date
2010-09-07T05:33:46Z (15 years ago)
From
Alexander Kann at TLS Tautenburg <kann@tls-tautenburg.de>
D. A. Kann, A. Nicuesa Guelbenzu, F. Ludwig and B. Stecklum (TLS
Tautenburg) report:
Further to Kann et al. (GCN 11238), we continued monitoring the afterglow
of GRB 100906A (Markwardt et al., GCN 11227) with the 1.34m TLS Schmidt
telescope under excellent conditions in intermittent intervals all night.
Beyond the 15 detections reported in Kann et al. (GCN 11238), we obtained
further nine Rc images (300 sec each) spread over the night, as well as
one further Ic (300 sec) and one further Z (600 sec) image at the end of
the night, during morning twilight. The afterglow is clearly detected in
all our images.
Due to crowding, we use SExtractor under GAIA to subtract background mesh
maps, then perform aperature photometry without needing to measure the
surrounding sky background (which is around 0). Errors are estimates based
on how clear the detection is, the last Rc frame was taken in strong
twilight already. We assume R2 = 15.9 for the USNOB1.0 star at RA =
01:54:55.247, Dec. = +55:38:31.40, and measure:
Midtime Rc dRc
0.247478 18.97 0.05
0.251517 19.06 0.05
0.255556 19.04 0.05
0.390570 19.08 0.05
0.430154 19.27 0.05
0.451022 19.18 0.05
0.498974 19.64 0.05
0.521231 19.62 0.05
0.525421 19.67 0.05
0.554113 19.80 0.05
0.570108 19.97 0.15
The afterglow seems to transition from a plateau phase (0.25 - 0.4 days)
to a much steeper decay.
Further observations are improbable due to upcoming inclement weather.
This message may be cited.
GCN Circular 11248
Subject
GRB 100906A: Fermi GBM observation
Date
2010-09-07T07:13:10Z (15 years ago)
From
David Gruber at MPE <dgruber@mpe.mpg.de>
David Gruber (MPE) reports on behalf of the Fermi GBM Team:
"At 13:49:27.63 UT on 06 September 2010, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 100906A (trigger 305473769 / 100906576)
which was also detected by the Swift-BAT (Markwardt et al. 2010, GCN 11227)
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight is 95 degrees.
The GBM light curve shows several bright peaks
with a duration (T90) of about 105 s (50-300 keV).
The time-averaged spectrum from T0 to T0+122 s is
best fit by a Band function with Epeak = 106.0 +17.5/-20.2 keV,
alpha = -1.34 +0.08/-0.06, and beta = -1.98 +0.06/-0.07.
(Castor C-stat 1044 for 479 d.o.f.)
The event fluence (10-1000 keV) in this time interval is
(2.64E-05 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+10.1 s in the 10-1000 keV band
is 14.45 +/- 0.29 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
GCN Circular 11249
Subject
GRB100906A: Optical observations at IAO
Date
2010-09-07T08:42:23Z (15 years ago)
From
Daisuke Kuroda at OAO/NAOJ <dikuroda@oao.nao.ac.jp>
D. Kuroda (OAO, NAOJ), H. Hanayama, T. Miyaji, J. Watanabe (IAO, NAOJ),
K. Yanagisawa (OAO, NAOJ), M. Yoshida (Hiroshima), K. Ohta (Kyoto)
and N. Kawai(Tokyo Tech) report on behalf of the MITSuME collaboration:
We observed the field of GRB 100906A (Markwardt et al., GCN 11227)
with the optical three color (g', Rc and Ic) CCD camera attached
to the Murikabushi 1m telescope of Ishigakijima Astronomical
Observatory.
The observation started on 2010-09-06 17:20:53 UT (~3.5 h after
the burst). We detected the previously reported afterglow
(Markwardt et al., GCN 11227; Ivanov et al., GCN 11228; Melandri
et al., GCN 12229) in all the three bands.
Photometric results of the OT are listed below.
We used GSC2.3 catalog for flux calibration.
#T0+[day] MID-UT T-EXP[sec] g' g'_err Rc Rc_err Ic Ic_err
----------------------------------------------------------------------
0.15249 17:29:02 840.0 19.3 0.1 18.3 0.1 17.6 0.1
----------------------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
GCN Circular 11250
Subject
GRB100906A: non-detection at 15GHz
Date
2010-09-07T10:08:45Z (15 years ago)
From
Guy Pooley at MRAO, Cambridge, UK <ggp1@cam.ac.uk>
The AMI Large Array (Cambridge, UK) was used to observe the field
of GRB 100906A (Markwardt et al, GCN11227) in the band 13.5 to 17.2 GHz
from 2010 Sep 06 23h31m to Sept 07 03h35m (starting 9h42m after the
trigger). The weather conditions were very poor and the noise levels
consequently high; no detection of GRB 100906A was made, with a formal
flux density at the UVOT position from GCN11227 of 380 microJy
and an rms noise of 136 microJy.
This message is quotable in publications.
Guy Pooley, on behalf of the AMI collaboration
GCN Circular 11251
Subject
Konus-Wind observation of GRB 100906A
Date
2010-09-07T10:27:34Z (15 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin,
P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf
of the Konus-Wind team, report:
The long GRB 100906A, (Swift/BAT trigger=433509:
Markwardt et.al, GCN 11227; Barthelmy et.al, GCN 11233)
triggered Konus-Wind at T0=49770.732s UT (13:49:30.732)
The burst light curve started with a complex ~20s-long structure,
followed by a weaker softer emission episode starting at ~T0+100 s.
The total duration of the burst is ~150 s.
The emission is seen up to 2 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB100906_T49770/
As observed by Konus-Wind the burst
had a fluence of (2.6 � 0.4)x10-5 erg/cm2,
and a 256-ms peak flux, measured from T0+9.728s,
of (2.7 � 0.3)x10-6 erg/cm2/s
(both in the 20 keV - 2 MeV energy range).
The time-integrated spectrum of the burst
(from T0 to T0+139.264 s) is best fit
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -1.5 (-0.2, +0.4),
the high energy photon index beta = -2.3 (<-2.0),
the peak energy Ep = 142(-60, +119) keV (chi2 = 84/60 dof).
The spectrum of the most intense part of the burst
(measured from T0+0.256 to T0+16.384 s) is best fit
in the 20 keV - 2 MeV range by the GRB (Band)
model, for which:
the low-energy photon index alpha = -1.1 (-0.1, +0.1),
the high energy photon index beta = -2.2 (-0.3, +0.2),
the peak energy Ep = 180(-40, +45) keV (chi2 = 68/60 dof).
The spectrum of the second bursting episode
(measured from T0+98.304 to T0+122.880 s) is best fit
in the 20 keV - 2 MeV range by the simple power law model with
the photon index = 2.55 (-0.2, +0.25), chi2 = 63/62 dof.
Assuming z=1.727 (Tanvir, Wiersema, and Levan et al., GCN 11230)
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.27, Omega_Lambda = 0.73,
the isotropic energy release E_iso = (2.2 � 0.4)x1053 erg,
the peak luminosity (L_iso)_max = (5.7 � 0.6)x1052 erg/s.
All the quoted results are preliminary.
All the quoted errors are at the 90% confidence level.
GCN Circular 11252
Subject
GRB100906A: R band observations
Date
2010-09-07T15:55:11Z (15 years ago)
From
Janos Kelemen at Konkoly Obs/Hungary <kelemen@konkoly.hu>
J. Kelemen and K. Sarneczky (Konkoly Observatory)
Z. Kuli and B. Ujhelyi (Hungarian Astronomical Association)
on behalf of the GRB OT observing program at the Konkoly Observatory.
On 09 september 2010 02:25:57 UT (45390 s after the burst) we observed the
field of GRB 100906A detected by Swift (trigger=433509; Markwardt et al.,
GCN 11227) with a 60/90 cm Schmidt telescope located at the Mountain Station
of the Konkoly Observatory using R filter. The exposure time of the CCD images
were 300 s. We clearly detected the fading afterglow at RA(J2000) = 01h 54m
44.12s Dec(J2000) = +55d 37' 49.3" (astrometry with ASTROMETRICA using UCAC3
catalogue.) with an uncertainty of 0.2 arcseconds.
Time Mag Error. Flag.
[s] [R] [1-sigma]
-------------------------------------
45390 20.6 0.1 -
45709 20.7 0.1 -
46028 21.3 0.1 -
-------------------------------------
The above magnitudes have not been corrected for the Galactic extinction.
GCN Circular 11253
Subject
GRB 100906A: GRAS-007 optical observations
Date
2010-09-07T17:19:18Z (15 years ago)
From
Veli-Pekka Hentunen at Taurus Hill Obs,A95 <veli-pekka.hentunen@kassiopeia.net>
Veli-Pekka Hentunen, Markku Nissinen and Tuomo Salmi (Taurus Hill
Observatory, Varkaus, Finland) report:
GRAS-007 PlaneWave CDK 17" F6.8 telescope and STL-11000M CCD camera
(Global-Rent-a-Scope, Nerpio, Spain) were used to detect GRB 100906A optical
afterglow. The observations were started at 2010-09-07 02:13:24 (UT) and
stopped at 2010-09-07 03:40:53 (UT). A number of unfiltered images with 120
sec and 600 sec exposure time were made. The afterglow was detected at
following position RA 01 54 44.12 and DEC +55 37 49.4 consistent those given
by Melandri A. et al. (GCN 11229) to within positional errors.
The following magnitude was obtained from the observations using USNO-B1.0
1456-0062169 (R = 15.70) as the comparison:
+T0 (hour) Filter Exp (sec) Mag Mag err Limit
13:00:24 (midpoint) unfiltered 3x600s 19.8 0.4 21.0
A JPG image of the 3x600 sec observations is available at the following URL:
http://cutenews.kassiopeia.net/data/upimages/GRB100906A.jpg
GCN Circular 11254
Subject
GRB 100906A: RTT150 optical observations
Date
2010-09-07T18:30:39Z (15 years ago)
From
Rodion Burenin at IKI, Moscow <rodion@hea.iki.rssi.ru>
A. Tkachenko (IKI), I. Khamitov (TUG),
R. Burenin, M. Pavlinsky, R. Sunyaev (IKI),
I. Bikmaev, N. Sakhibullin (KSU/AST),
Z. Eker (TUG), U. Kiziloglu (METU), E. Gogus (Sabanci Uni.)
The optical counterpart of GRB 100906A (GCN 11227) was observed with
Russian-Turkish 1.5-m telescope (RTT150, Bakirlitepe, TUBITAK National
Observatory, Turkey), starting at Sep 06, 19:28 UT, i.e. ~5.64 hours after
the burst, using TFOSC.
Three series of BRI frames were made under moderate weather conditions. The
afterglow is clearly detected in all images.
Assuming the star at RA = 01:54:46.82, Dec. = +55:37:55.3 to have USNOB1.0
R2MAG = 15.70, we estimated the following magnitudes for the OT on combined
images of every set:
t-t0 band mag err
6.048 h R 18.80 0.02
9.610 h R 19.08 0.02
13.554 h R 19.69 0.04
The color of the afterglow changes from (B-R)=1.21 to (B-R)=1.31 at the
beniginning and at the end of our observations.
GCN Circular 11259
Subject
GRB100906A: detection at 15GHz
Date
2010-09-09T10:16:04Z (15 years ago)
From
Guy Pooley at MRAO, Cambridge, UK <ggp1@cam.ac.uk>
The AMI Large Array (Cambridge, UK) was used to make two further
observations of the field of GRB 100906A (Markwardt et al, GCN11227)
in the band 13.5 to 17.2 GHz (GCN11250 reports the first observation).
date/time flux sigma / microJy
2010 Sep 08 06h51m to Sep 08 07h51m 137 140
2010 Sep 08 22h03m to Sep 09 00h18m 465 70
The GRB is clearly detected in the second of these observations,
mean time 57h17m after the trigger.
(A radio source catalogued in NVSS, 87GB, 7C is also visible in the
field near 01 55 11 +55 35 20 (J2000), about 4.5 arcmin from the GRB.)
This message is quotable in publications.
Guy Pooley, on behalf of the AMI collaboration
GCN Circular 11267
Subject
GRB 100906A: optical observations at Mt.Terskol
Date
2010-09-10T02:44:31Z (15 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
M. Andreev, A. Sergeev (Terskol Branch of Institute of Astronomy),
A.Pozanenko (IKI), N. Parakhin, S. Velichko, N. Borachok (IC AMER)
V. Petkov (Baksan Neutrino Observatory INR RAS) on behalf of larger GRB
follow up collaboration report:
We observed the field of Swift GRB 100906A (Markwardt et al., GCN 11227)
with Zeiss-2000 telescope of Mt.Terskol observatory starting Sep. 06 (UT)
23:56. We obtained images in g,V, r filters. The afterglow (Markwardt et al.
GCN 11227, Ivanov et al. GCN 11228, Melandri et al. GCN 11229) is clealy
detected in all filters. The preliminary photometry is based on GSC2.3
catalog and Jordi et al. (2006) UBVRcIc -> ugriz transformations:
T0+ Filter, Exp. OT
(d)
0.4213 r 6x120 19.43 +/-0.03
0.4626 g 10x120 20.11 +/-0.02
0.4785 V 7x120 19.77 +/-0.03
GCN Circular 11291
Subject
GRB100906A: Ashra-1 observation of early optical emission
Date
2010-09-19T07:17:24Z (15 years ago)
From
Makoto Sasaki at ICRR/U.Tokyo <sasakim@icrr.u-tokyo.ac.jp>
Y.Asaoka, S.Hirai, T.Itoh, M.Masuda, Y.Morimoto, K.Ota, M.Sasaki
(ICRR,Univ.Tokyo), D.Kogure, S.Ogawa, H.Tsujikawa (Toho Univ.),
P.Binder (Univ.Hawaii Hilo), J.Learned (Univ.Hawaii Manoa)
report on behalf of the Ashra-1 collaboration:
We have searched for optical emission in the field of GRB100906A
(Markwardt, et al., GCN Circ. 11227) around the BAT-triggered GRB time
(T0) with one of the light collector units in the Ashra-1 detector
(http://www.icrr.u-tokyo.ac.jp/~ashra) on Mauna Loa on Hawaii Island
(latitude = 19.5412 deg. N, longitude =155.5676 deg. W, altitude =3330m).
The Ashra-1 light collector unit has the achieved resolution of a few
arcmin, viewing 42 degree circle region of which center is located at
Alt = 60 deg, Azi = 0 deg. The sensitive region of wavelength is
similar to the B-band.
We quickly analyzed 200 images covering the field of GRB100906A every
6s with 4s exposure time respectively during the observation between
T0-600s and T0+600s. We detected no new optical object within the PSF
resolution around the GRB100906A determined by Swift-UVOT (Markwardt,
et al., GCN Circ. 11227)
As a result of our preliminary analysis, the following 3-sigma limiting
magnitudes are derived:
----------------------------------------------------------------------
Starting&Ending Exp.Time, 3-sigma Limit. Mag.
----------------------------------------------------------------------
-593.2 -589.2 12.1
-587.3 -583.3 12.2
. . .
. . .
-1.4 2.6 12.0
4.5 8.5 12.1
. . .
. . .
590.5 594.5 12.2
596.4 600.4 12.1
----------------------------------------------------------------------
The limiting magnitudes were estimated in comparison with stars in
Tycho-2 Catalog to be distributed between 12.0 and 12.2 as above
partly listed.
Figures of limiting optical magnitudes vs time comparing with other
measurements and can be found at: http://www.icrr.u-tokyo.ac.jp/~ashra/GRB100906A.
This message may be cited.
====================================
SASAKI Makoto
ICRR, University of Tokyo
5-1-5 Kashiwa-no-ha Kashiwa 277-8582
tel/fax +81-4-7136-3143
====================================
GCN Circular 11340
Subject
GRB 100906A: D50 optical detection
Date
2010-10-13T16:00:35Z (15 years ago)
From
Jan Strobl at AI AS CR,Ondrejov <jan@strobl.cz>
Jan Strobl (1,2), Martin Blazek (1,2), Martin Jelinek (3), Cyril Polasek
(1), Petr Kubanek (3,4), Martin Nekola (1), Matus Kocka (1) and
Rene Hudec (1,2)
(1. ASU AVCR Ondrejov, 2. FEL CVUT Praha, 3. IAA Granada, 4. IPL UV
Valencia)
We report on the observation of the Swift GRB 100906A (Markwardt et al.,
GCN 11227) with the 0.5m telescope D50 in Ondrejov (Czech Republic),
starting at 21:17:37 UT, i.e. ~7.5h after the trigger. Eventually, six
hours of observational data were obtained, with the last image taken at
3:23:20 UT.
We clearly detect the afterglow reported by Ivanov et al. (GCN 11228),
and at the the beginning of our sequence (coadded first 7x 20s, exp.
mean time = 21:19 UT) we measure a magnitude 18.7 +- 0.2.
This message can be cited.
GCN Circular 11395
Subject
GRB 100906A: optical observations
Date
2010-11-11T17:56:47Z (15 years ago)
From
Alina Volnova at SAI MSU <alinusss@gmail.com>
A. Volnova (SAI MSU), A. Pozanenko (IKI), M. Andreev, A. Sergeev
(Terskol Branch
of Institute of Astronomy), V. Rumyantsev, K. Grankin (CrAO), A.
Erofeeva, G. Kornienko (UAFO), I. Molotov (ISON), E. Klunko (ISTPM),
Ibrahimov (MAO), B. Satovski (Astrotel) on behalf of GRB follow up
collaboration report:
We observed the optical afterglow (Markwardt et al. GCN 11227, Ivanov
et al. GCN 1128) of GRB 100906A (Markwardt et al. GCN 11227) with the
following telescopes: GAS-250 (Ussuriysk Astrophysical Observatory),
AZT-14 (Mondy observatory), Zeiss-2000 and Zeiss-600 (Mt.Terskol
observatory), Shajn telescope (CrAO) and AZT-22 (Maidanak
observatory). Observations started at 14:02 UT, i.e. approximately 13
minutes after the burst trigger. Observations in different optical
bands (B, V, R, I, g, r) cover the period of t-t_0 from 0.12 up to
2.46 days. The photometry calibration was made against several stars
of GSC2.3 catalog. The light curve of GRB 100906A afterglow can be
found at
http://grb.rssi.ru/GRB100906A/GRB100906A_lc.png .
From the R band of light curve one can see a clear break around ~0.5
days after the burst with alpha_1 = -0.7 +/- 0.1 before and alpha_2 =
-2.0 +/- 0.3 after break.
Color index B-R measured between 0.22 and 0.24 days after the burst
does not change within the error bars and is equal to 1.33 +/- 0.12,
while the B-R index measured at 1.26 days after the burst trigger is
equal to 1.61+/- 0.19.