- GCN Circular #17131
S. Golenetskii, R. Aptekar, V. Pal'shin, D. Frederiks, D. Svinkin,
and T. Cline on behalf of the Konus-Wind team,
K. Hurley and J. Goldsten, on behalf of the MESSENGER NS GRB team,
V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein,
on behalf of the Fermi GBM team,
A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo,
and C. Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, and
S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, report:
The short-duration, hard-spectrum GRB 141202A has been observed by Fermi
(GBM trigger 439211828), MESSENGER (GRNS), INTEGRAL (SPI-ACS),
Konus-Wind, and Swift (BAT), so far, at about 40626 s UT (11:17:06).
This burst occurred just after Swift started a preplanned slew maneuver.
There are no BAT event data covering the burst interval, but from the
energy response of the quadrant rates, it appears that the source was
partially coded in BAT.
We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
---------------------------------------------
RA(2000), deg Dec(2000), deg
---------------------------------------------
Center:
143.073 (09h 32m 17s) +54.161 (+54d 09' 38")
Corners:
142.732 (09h 30m 56s) +52.555 (+52d 33' 17")
143.092 (09h 32m 22s) +53.247 (+53d 14' 51")
143.397 (09h 33m 35s) +55.706 (+55d 42' 22")
143.039 (09h 32m 09s) +55.054 (+55d 03' 15")
---------------------------------------------
The error box area is 1439 sq. arcmin, and its maximum
dimension is 3.2 deg (the minimum one is 10 arcmin).
The Sun distance was 117 deg.
This box may be improved.
A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB141202_T40626/IPN/
The time history and spectrum will be given in forthcoming GCN Circulars.
- GCN Circular #17132
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a series of observations, tiled on the sky, of the
IPN GRB 141202A. Automated analysis of the XRT data will
be presented online at http://www.swift.ac.uk/xrt_products/TILED_GRB00033
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. The probability of finding
serendipitous sources, unrelated to the IPN event is high: any X-ray source
considered to be a probable afterglow candidate will be reported via a GCN Circular
after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; and 2009, MNRAS, 397, 1177).
This circular is an official product of the Swift-XRT team.
- GCN Circular #17133
O.J. Roberts (UCD) reports on behalf of the Fermi GBM Team:
"At 11:17:05.61 UT on the 2nd of December 2014, the
Fermi Gamma-Ray Burst Monitor triggered and located
GRB 141202A (trigger 439211828 / 141202470 ). The
GBM on-ground location, using the Fermi GBM trigger
data, is RA = 145.0, Dec =+59.9, with an uncertainty of
3.3 degrees (radius, 1-sigma containment,statistical only;
there is additionally a systematic error which is currently
estimated to be 2 to 3 degrees). The GBM location is
consistent with the IPN Triangulation (Golenetskii et al.
2014, GCN 17131).
The angle from the Fermi LAT boresight is about
78 degrees.
The GBM light curve consists of a single peak with a
duration (T90) of about 1.3 s (50-300 keV). The
time-averaged spectrum from T0+0.0 s to T0+1.3 s is
adequately fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.11 +/- 0.08
and the cutoff energy, parameterized as Epeak, is
596 +/- 40 keV.
The event fluence (10-1000 keV) in this time interval is
(4.2 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux
measured starting from T0+0.1 s in the 10-1000 keV band
is 8.4 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
- GCN Circular #17134
C. Pagani and P. A. Evans (U. Leicester) report on behalf of the Swift team:
Swift-XRT has observed the error box of the IPN GRB 141202A (Golenetskii et al., GCN Circ. 17131) in a series of observations tiled on the sky. The total exposure time is 12.3 ks spread over 7 fields; the maximum exposure within the sky observed was 2.7 ks. The observations started 93.5 ks after the IPN trigger and extended over ~50.8 ks.
Within these data no credible X-ray afterglow is detected. The 3-sigma upper limit is 5.2E-03 cts s^-1 (0.3-10 keV). The automated analysis of the XRT data detects three X-ray sources that are classified as possible afterglow candidates, but inspection of the data shows these to be artifacts due to contamination by the bright Earth.
The automated analysis is reported online at http://www.swift.ac.uk/xrt_products/TILED_GRB00033
This circular is an official product of the Swift-XRT team.
- GCN Circular #17136
S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:
The short-duration, hard-spectrum GRB 141202A
(IPN triangulation: Golenetskii et al., GCN 17131;
Fermi GBM detection: Roberts, GCN 17133)
triggered Konus-Wind at T0=40626.305 s UT (11:17:06.305).
The burst light curve shows a single pulse with a duration of ~1.4 s.
The emission is seen up to ~10 MeV.
As observed by Konus-Wind, the burst
had a fluence of 4.44(-1.02,+1.47)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.624 s,
of 7.37(-2.00,+2.67)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum of the burst
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.49(-0.35,+0.47),
and Ep = 538(-150,+274) keV (chi2 = 77/84 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index:
beta < -2.0 (chi2 = 77/83 dof).
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB141202_T40626/
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
- GCN Circular #17139
F. E. Marshall (NASA/GSFC) and S. B. Cenko (NASA/GSFC)
report on behalf of the Swift/UVOT team:
The short/hard GRB 141202A was localized to a 1439 sq. arcmin
error box with the IPN (Golenetskii et al. GCN Circ. 17131), and
Swift tiled the error box with 7 fields starting
93.5 ks after the trigger. No credible afterglow was detected
with the Swift/XRT (Pagani et al. GCN Circ. 17134).
In two exposures with the U filter starting 128 ks after the trigger,
Swift/UVOT finds a bright source just outside the IPN error region
that is not seen in the DSS or the SDSS. In addition, no source at this position
was found with the Minor Planet Checker. There is a dim SDSS
galaxy with a g' magnitude (AB) of 23.0 +/- 0.2 coincident with the UVOT source.
A 3-sigma upper limit for this galaxy in the u' band is 22.4 mag.
The preliminary UVOT position is:
RA (J2000) = 09:32:29.78 = 143.12408 (deg.)
Dec (J2000) = 55:19:44.4 = 55.32899 (deg.)
with an estimated uncertainty of 0.5 arcsec. (radius, 90% confidence).
There is very marginal evidence (1.8-sigma) for variability between
the two UVOT observations. The preliminary
AB magnitudes using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) is:
Filter T_start(ks) T_stop(ks) Exp(ks) Mag (AB)
u 127.9 128.6 0.69 20.43 +/- 0.09
u 129.4 130.3 0.88 20.69 +/- 0.13
No correction is made for the Galactic extinction
due to the reddening of E(B-V) = 0.02 in the direction of the source
(Schlegel et al. 1998).
The 3-sigma upper limit for the XRT count rate at the position of the
UVOT source is 9.6e-3 counts/s in the 0.3-10 keV band.
It would be very unusual for UVOT to find a bright optical afterglow for
a short/hard GRB so long after the trigger, especially since
XRT did not find an afterglow. The long-term increase in the optical flux by
a factor of at least 6 indicates that this may nevertheless be an
interesting object.
- GCN Circular #17153
J. Capone (UMD), V. Toy (UMD), A. Cucchiara (NASA-GSFC), S.B. Cenko
(NASA-GSFC), E. Troja (NASA-GSFC), A. Kutyrev (NASA-GSFC), and S. Veilleux
(UMD) report on behalf of a larger collaboration:
We observed the field of the variable source reported by Marshall and Cenko
(GCN 17139) with the Large Monolithic Imager (LMI) on the 4.3m Discovery
Channel Telescope (DCT) at Happy Jack, AZ from 2014/12/07 11:01 until
2014/12/07 11:08 UTC (starting 119.74 hours after the observations reported
by Golenetskii et al. in GCN 17131). A source is clearly detected at the
location of the source identified by UVOT in u', g', r', i' and z'. Using
nearby point sources from SDSS for calibration we measure r' = 20.57 +/-
0.03. The coincident SDSS R10 source has r' = 22.65 +/- 0.20, confirming
that the source is indeed transient. At 0.8 arcsecond seeing, the source is
unresolved.
This magnitude is reported in AB magnitude and is not corrected for
Galactic extinction in the direction of the source.
Further observations are planned to investigate possible variability of
this source.
We thank the staff of the Discovery Channel Telescope for assistance with
these observations.
- GCN Circular #17192
J. Enomoto, M. Tashiro, Y. Terada, T. Yasuda, S. Koyama, S. Takeda,
S. Nakaya, T. Fujinuma, S. Matsuoka (Saitama U.), M. Yamauchi,
N. Ohmori, R. Kinoshita (Univ. of Miyazaki), W. Iwakiri (RIKEN),
K. Yamaoka (Nagoya U.), S. Sugita (Ehime U.),Y. Hanabata (ICRR),
M. Ohno, T. Kawano, S. Furui, Y. Fukazawa (Hiroshima U.),
Y. E. Nakagawa, M. Kokubun, T. Takahashi (ISAS/JAXA),
Y. Urata (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo)
on behalf of the Suzaku WAM team, report:
The short and IPN localized GRB 141202A (IPN localization: S.
Golenetskii et al., GCN 17131; Fermi GBM Detection: O.J. Roberts et al.,
GCN 17133; Konus-Wind observation: S. Golenetskii et al., GCN 17136)
triggered the Suzaku Wide-band All-sky Monitor (WAM) which covers an
energy range of 50 keV - 5 MeV at 11:17:5.508 UT (=T0).
The observed light curve shows a multi-peaked structure lasting from T0s
to T0+2s, followed by a weaker emission seen with a duration (T90) of
about 1.8 seconds. The fluence in 100 - 1000 keV was
4.48 (-0.18, +0.10) x 10^-6 erg/cm^2. The 1-s peak flux measured from
T0+0.5s was 7.61 (-2.44, -0.11) photons/cm^2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0 s to
T0+2 s is well fitted by a power-law with exponential cutoff model:
dN/dE ~ E^{-alpha} * exp(-(2-alpha)*E/Epeak) with
alpha 0.28 (-0.56, +0.48), and
Epeak 565 (-66, +96) keV (chi^2/d.o.f. = 24.5/25).
All the quoted errors are at statistical 90% confidence level, in which
the systematic uncertainties are not included.
The light curves for this burst will be available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html
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