GRB 100905A
GCN Circular 11214
Subject
GRB 100905A: Swift detection of a burst
Date
2010-09-05T15:24:02Z (15 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
F. E. Marshall (NASA/GSFC), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), D. N. Burrows (PSU),
P. A. Evans (U Leicester), N. Gehrels (NASA/GSFC),
J. M. Gelbord (PSU), C. Guidorzi (U Ferrara),
S. T. Holland (CRESST/USRA/GSFC), P. T. O'Brien (U Leicester),
K. L. Page (U Leicester), D. M. Palmer (LANL),
A. Rowlinson (U Leicester), B. Sbarufatti (INAF-OAB/IASFPA),
M. H. Siegel (PSU), E. Troja (NASA/GSFC/ORAU) and
T. N. Ukwatta (GSFC/GWU) report on behalf of the Swift Team:
At 15:08:14 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 100905A (trigger=433442). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 31.530, +14.932 which is
RA(J2000) = 02h 06m 07s
Dec(J2000) = +14d 55' 54"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a single peak
structure with a duration of about 6 sec. The peak count rate
was ~1500 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 15:09:29.9 UT, 75.2 seconds after
the BAT trigger. Using promptly downlinked data we find an uncatalogued
X-ray source with an enhanced position: RA, Dec 31.5505, 14.9300 which
is equivalent to:
RA(J2000) = 02h 06m 12.12s
Dec(J2000) = +14d 55' 47.9"
with an uncertainty of 2.3 arcseconds (radius, 90% containment). This
location is 71 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 consistent with the Galactic value of 5.35
x 10^20 cm^-2 (Kalberla et al. 2005).
UVOT took a finding chart exposure of 150 seconds with the White
filter starting 77 seconds after the BAT trigger. No credible
afterglow candidate has been found in the initial data products. The
2.7'x2.7' sub-image covers 100% of the XRT error circle. The 3-sigma
upper limit is typically 19.3 mag. The 8'x8' region for the list of
sources generated on-board covers 100% of the XRT error circle. The
list of sources is typically complete to about 18 mag. No correction
has been made for the expected extinction corresponding to E(B-V) of
0.06.
Burst Advocate for this burst is F. E. Marshall (marshall AT milkyway.gsfc.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 11215
Subject
GRB 100905A: Faulkes Telescope North observations
Date
2010-09-05T15:57:12Z (15 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), I. A. Steele, C. G. Mundell (LJMU),
A. Gomboc (U. Ljubljana) report on behalf of a large collaboration:
The Faulkes Telescope North automatically began observing Swift
GRB 100905A (Marshall et al. GCN Circ. 11214) on September 05,
15:10:32 UT, 138 s from the GRB trigger time.
Within the XRT error circle we do not find any source down to
the following limiting magnitudes:
Mid Time from Exposure Filter Lim. Mag.
GRB (s) (s)
-------------------------------------------------------
179 3x10 R > 19.8
604 120 R > 20.0
839 100 i' > 19.0
-------------------------------------------------------
Magnitudes are calibrated against nearby USNOB-1 stars
R2 and I values.
Observations stopped soon due to twilight.
GCN Circular 11216
Subject
GRB 100905A: MASTER Prompt Optical Observations
Date
2010-09-05T17:43:04Z (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
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
V.Yurkov, Yu.Sergienko, D.Varda, I.Kudelina
Blagoveschensk Educational State University, Blagoveschensk
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located at Tunka was pointed to the Swift GRB 100905A (Marshall et al.
GCN Circ. 11214) 33 sec after Notice time (55 s after GRB trigger time)
in two polarizations bands.
There is no optical transient at XRT position (Marshall et al.
GCN Circ. 11214).
Following data has been received:
start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd? Band
--------------------------------------------------------------------------
15:09:10 15:09:20 10 16.5 55.0 N Polariz
15:09:39 19:09:59 20 17.1 84.0 N Polariz
15:10:45 15:11:15 30 17.3 150.0 N Polariz
15:11:35 15:12:15 40 17.5 200.0 N Polariz
--------------------------------------------------------------------------
The observations and data reductions is continued.
The message may be cited.
GCN Circular 11218
Subject
GRB 100905A: Swift-BAT refined analysis
Date
2010-09-05T21:39:43Z (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),
F. E. Marshall (NASA/GSFC), 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 100905A (trigger #433442)
(Marshall, et al., GCN Circ. 11214). The BAT ground-calculated position is
RA, Dec = 31.542, 14.919 deg, which is
RA(J2000) = 02h 06m 10.0s
Dec(J2000) = +14d 55' 08.2"
with an uncertainty of 1.7 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve shows a single peak starting at ~T-1.7 sec,
peaking at ~T+0.5 sec, and ending at ~T+3 sec. T90 (15-350 keV) is
3.4 +- 0.5 sec (estimated error including systematics).
The time-averaged spectrum from T-1.6 to T+2.1 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.09 +- 0.19. The fluence in the 15-150 keV band is 1.7 +- 0.2 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T+0.03 sec in the 15-150 keV band
is 0.6 +- 0.1 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/433442/BA/
GCN Circular 11219
Subject
GRB 100905A: Enhanced Swift-XRT position
Date
2010-09-05T21:51:09Z (15 years ago)
From
Phil Evans at U of Leicester <pae9@star.le.ac.uk>
P.A. Evans, M.R. Goad, J.P. Osborne and A.P. Beardmore (U. Leicester)
report on behalf of the Swift-XRT team.
Using 1956 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 100905A, 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 = 31.55023, +14.92941 which is equivalent
to:
RA (J2000): 02h 06m 12.06s
Dec (J2000): +14d 55' 45.9"
with an uncertainty of 1.6 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 11220
Subject
GRB100905A: 1.5m OSN upper limit
Date
2010-09-06T01:16:38Z (15 years ago)
From
Antonio Deugarte at IAA-CSIC <deugarte@iaa.es>
A. Sota (IAA-CSIC), A. de Ugarte Postigo (DARK/NBI),
A.J. Castro-Tirado (IAA-CSIC) report on behalf of a
larger collaboration:
"We have observed the field of GRB100905A (Marshall et al.
GCNC 11214) using the 1.5m telescope of the Observatorio
de Sierra Nevada, in Granada (Spain). In a 7x300s combined
I-band frame, with mean epoch September 5.9792 UT (8.36 hours
after the burst onset), we do not detect any new source within
the enhanced XRT position (Evans et al. GCNC 11219) down to a
3-sigma limiting magnitude of 22.8. USNO-B1.0 has been used as
reference catalogue."
GCN Circular 11222
Subject
GRB 100905A: UKIRT zJHK Observation
Date
2010-09-06T04:55:03Z (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
We observed GRB 100905A (Marshall et al. GCN 11214) in z, J, H,
and K filters using UKIRT. The observation started at Sept. 05,
15:22 UT or roughly 17 minutes after the BAT alert, until the
sunrise.
The reduced images with non-optimal calibration frames show
a "possible" very faint source within the XRT error circle
(Evans et al. GCN 11219) whose significance is only 2-3 sigma
in each image (2-sigma limit, J=19.8, H=19.0,
and K=18.7 mag). The faint smudge show up in all zJHK filter
images, suggesting this could be an afterglow, but we do not
exclude the possibility that this is just a spurious detection.
Further analysis of the UKIRT data is ongoing.
GCN Circular 11223
Subject
GRB 100905A: Swift-XRT refined analysis.
Date
2010-09-06T08:08:17Z (15 years ago)
From
Phil Evans at U of Leicester <pae9@star.le.ac.uk>
P.A. Evans (U. Leicester) and F. E. Marshall (NASA/GSFC) report on
behalf of the Swift-XRT team:
We have analysed 7.1 ks of XRT data for GRB 100905A (Marshall et al. GCN
Circ. 11214), from 78 s to 13.6 ks after the BAT trigger. The data
comprise 71 s in Windowed Timing (WT) mode with the remainder in Photon
Counting (PC) mode. The enhanced XRT position for this burst was given
by Evans et al. (GCN. Circ 11219).
The light curve shows some initial flaring activity, with the flares
peaking at around 290, 320 and 400 s after the trigger. The flares peak
an order of magnitude brighter than the underlying emission, which
can be modelled with a single power-law, with a decay index of
alpha=0.86 (+/-0.06).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 3.0 (+/-0.3). The best-fitting
absorption column is 1.9 (+0.6, -0.5) x 10^21 cm^-2, in excess of the
Galactic value of 5.4 x 10^20 cm^-2 (Kalberla et al. 2005). The PC mode
spectrum has a photon index of 1.97 (+0.12, -0.18) and a best-fitting
absorption column of 8.4 (+4.1, -2.8) x 10^20 cm^-2. The counts to
observed (unabsorbed) 0.3-10 keV flux conversion factor deduced from
this spectrum is 3.9 x 10^-11 (4.8 x 10^-11) erg cm^-2 count^-1.
If the light curve continues to decay with a power-law decay index of
0.86, the count rate at T+24 hours will be 2.7 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 1.1 x
10^-13 (1.3 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/00433442.
This circular is an official product of the Swift-XRT team.
GCN Circular 11224
Subject
GRB100905A: MITSuME Okayama optical upper limits
Date
2010-09-06T08:57:02Z (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 100905A (Marshall et al., GCN 11214)
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 2010-09-05 15:31:18 UT (~23 min after
the burst). We did not find any new point source within the
enhanced XRT error circle (Evans et al., GCNC 11219) in all
the three bands.
Three sigma upper limits of the OT are listed below. We used
SDSS catalog for flux calibration.
T0+[day] MID-UT T-EXP[sec] g' Rc Ic
------------------------------------------------------
0.09641 17:27:05 10380.0 >20.9 >20.6 >19.7
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
GCN Circular 11225
Subject
GRB100905A: Optical upper limits at IAO
Date
2010-09-06T08:58:15Z (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 100905A (Marshall et al., GCN 11214)
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 2010-09-05 18:56:36 UT (~0.16 day after the
burst). We did not find any new point source within the enhanced XRT
error circle (Evans et al., GCNC 11219) in all the three bands.
Three sigma upper limits of the OT are listed below. We used
SDSS catalog for flux calibration.
T0+[day] MID-UT T-EXP[sec] g' Rc Ic
------------------------------------------------------
0.16300 19:02:58 1440.0 >21.1 >21.4 >19.5
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
GCN Circular 11237
Subject
GRB 100905A: Swift/UVOT Upper Limits
Date
2010-09-06T19:08:45Z (15 years ago)
From
Mike Siegel at PSU/Swift MOC <siegel@astro.psu.edu>
M. H. Siegel (PSU) and F. E. Marshall (NASA/GSFC) report on behalf
of the Swift/UVOT team.
The Swift/UVOT began settled observations of the field of
GRB 100905A 77s after the BAT trigger (Marshall et al.,
GCN Circ. 11214). Data summed from the first and second orbits
do not reveal a source at the enhanced position of the X-ray
afterglow (Evans et al., GCN Circ. 11219).
The 3-sigma upper limits for the finding chart (fc) and
summed exposures are reported below:
FILTER T_start(s) T_stop Exposure Mag/3UL
========================================================
white fc 78 228 147 >20.77
white 78 2055 450 >21.29
V 619 1933 155 >19.01
B 545 2031 155 >19.81
u fc 290 540 245 >20.08
u 290 2006 381 >20.17
uvw1 668 1982 155 >19.53
uvm2 5654 7290 393 >20.19
uvw2 5245 12865 1278 >21.26
=======================================================
The above magnitudes are not corrected for the Galactic extinction
corresponding to a reddening of E_{B-V} = 0.06 (Schlegel et al.,
1998, ApJS, 500, 525). The photometry is on the UVOT photometric
system described in Poole et al. (2008, MNRAS, 383, 627).