GRB 161113A
GCN Circular 20172
Subject
GRB 161113A: Swift detection of a burst
Date
2016-11-13T17:51:19Z (9 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
P. D'Avanzo (INAF-OAB), S. D. Barthelmy (GSFC), D. N. Burrows (PSU),
J. A. Kennea (PSU), H. A. Krimm (CRESST/NSF/USRA),
A. Y. Lien (GSFC/UMBC), D. M. Palmer (LANL),
B. Sbarufatti (INAF-OAB/PSU) and M. H. Siegel (PSU) report on behalf
of the Swift Team:
At 17:30:26 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 161113A (trigger=722063). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 179.834, -5.347, which is
RA(J2000) = 11h 59m 20s
Dec(J2000) = -05d 20' 49"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows two overlapping peaks
with a total duration of about 45 sec. The peak count rate
was ~2400 counts/sec (15-350 keV), at ~15 sec after the trigger.
The XRT began observing the field at 17:31:18.5 UT, 51.8 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 179.79351,
-5.30848 which is equivalent to:
RA(J2000) = 11h 59m 10.44s
Dec(J2000) = -05d 18' 30.5"
with an uncertainty of 3.8 arcseconds (radius, 90% containment). This
location is 200 arcseconds from the BAT onboard position. 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 (2.11 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 6.5
(+6.17/-4.70) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 1.07e-08 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 78 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 typical 3-sigma upper limit has been about 19.6 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
0.02.
Burst Advocate for this burst is P. D'Avanzo (paolo.davanzo AT brera.inaf.it).
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 20173
Subject
GRB 161113A: RATIR Optical and NIR Observations
Date
2016-11-14T17:56:08Z (9 years ago)
From
Nat Butler at Az State U <natbutler@asu.edu>
Nat Butler (ASU), Alan M. Watson (UNAM), Alexander Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Ori Fox (STScI), J. Xavier
Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora
Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jos�� A.
de Diego (UNAM), Leonid Georgiev (UNAM), Jes��s Gonz��lez (UNAM), Carlos
Rom��n-Z����iga (UNAM), Neil Gehrels (GSFC), Harvey Moseley (GSFC), John
Capone (UMD), V. Zach Golkhou (ASU), and Vicki Toy (UMD) report:
We observed the field of GRB 161113A (D'Avanzo, et al., GCN 20172) with the
Reionization and Transients Infrared Camera (RATIR; www.ratir.org) on the
1.5m Harold Johnson Telescope at the Observatorio Astron��mico Nacional on
Sierra San Pedro M��rtir from 2016/11 14.48 to 2016/11 14.52 UTC (17.94 to
19.01 hours after the BAT trigger), obtaining a total of 0.71 hours
exposure in the r and i bands and 0.14 hours exposure in the Z, Y, and H
bands.
For a source within the Swift-XRT error circle, in comparison with the
USNO-B1 and 2MASS catalogs, we obtain the following upper limits (3-sigma):
r > 22.41
i > 22.18
Z > 21.21
Y > 20.72
H > 18.83
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 20174
Subject
GRB 161113A: Enhanced Swift-XRT position
Date
2016-11-14T18:34:34Z (9 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.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 2998 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 161113A, 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 = 179.79452, -5.30897 which is equivalent
to:
RA (J2000): 11h 59m 10.68s
Dec (J2000): -05d 18' 32.3"
with an uncertainty of 2.2 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 20175
Subject
GRB 161113A: Kuban State University optical upper limit
Date
2016-11-14T19:08:55Z (9 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Ivanov (KubSU), V. Ivanov (KubSU), V. Lysenko
(KubSU), D. Ivanova (KubSU), A. Volnova (IKI), A. Pozanenko (IKI) report
on behalf of larger GRB follow-up collaboration:
We observed the field of GRB 161113A (D'Avanzo, et al., GCN 20172) with
the RC510 telescope (0.51-m f/8) of Kuban State University Astrophysical
Observatory. We obtained several unfiltered images starting on Nov.
14 (UT) 02:02:08. Within enhanced XRT position (Evans et al., GCN 20174)
we do not detect any source. Preliminary photometry of the field is
following
Date UT start t-T0 Filter Exp. OT Err. UL(3 sigma)
(mid, days) (s)
2016-11-14 02:02:08 0.37062 CR 52*30 n/d n/d 18.9
Photometry is based on nearby USNO-B1.0 stars (R2 magnitudes).
GCN Circular 20176
Subject
GRB 161113A: Swift-XRT refined Analysis
Date
2016-11-15T08:12:35Z (9 years ago)
From
Paolo D'Avanzo at INAF-OAB <paolo.davanzo@brera.inaf.it>
J.P. Osborne (U. Leicester), K.L. Page (U. Leicester), A. Melandri
(INAF-OAB), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), B. Sbarufatti
(INAF-OAB/PSU), D.N. Burrows (PSU), T.G.R. Roegiers (PSU), B. Mingo (U.
Leicester) report on behalf of the Swift-XRT team:
We have analysed 23 ks of XRT data for GRB 161113A (D'Avanzo et al. GCN
Circ. 20172), from 42 s to 74.9 ks after the BAT trigger. The data
comprise 118 s in Windowed Timing (WT) mode (the first 8 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 Evans et
al. (GCN Circ. 20174).
The light curve can be modelled with a series of power-law decays. The
initial decay index is alpha=2.52 (+0.25, -0.28). At T+109 s the decay
steepens to an alpha of 6.0 (+0.5, -0.4) before breaking again at T+272
s to a final decay with index alpha=0.45 (+0.04, -0.05).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.82 (+/-0.09). The
best-fitting absorption column is 3.63 (+0.29, -0.27) x 10^21 cm^-2,
in excess of the Galactic value of 2.1 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 2.03 (+0.22, -0.21)
and a best-fitting absorption column of 1.2 (+0.6, -0.5) x 10^21 cm^-2.
The counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 3.3 x 10^-11 (4.1 x 10^-11) erg cm^-2
count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 1.2 (+0.6, -0.5) x 10^21 cm^-2
Galactic foreground: 2.1 x 10^20 cm^-2
Excess significance: 3.0 sigma
Photon index: 2.03 (+0.22, -0.21)
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00722063.
This circular is an official product of the Swift-XRT team.
GCN Circular 20177
Subject
GRB 161113A: Swift/UVOT Upper Limits
Date
2016-11-15T13:15:18Z (9 years ago)
From
Alice Breeveld at MSSL-UCL <a.breeveld@ucl.ac.uk>
A. A. Breeveld (UCL-MSSL), P. D'Avanzo (INAF-OAB) and S. W. K. Emery
(UCL-MSSL) report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 161113A 61
s after the BAT trigger (D'Avanzo et al., GCN Circ. 20172).
No optical afterglow consistent with the XRT position (Evans et al. GCN
Circ. 20174) is detected in the initial UVOT exposures. Preliminary
3-sigma upper limits using the UVOT photometric system (Breeveld et al.
2011, AIP Conf. Proc. 1358, 373) for the first finding chart (FC)
exposures and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 61 211 147 >19.8
u_FC 274 483 206 >18.8
white 555 6332 369 >21.0
v 5152 5352 197 >19.2
b 4537 6171 393 >20.1
u 274 5966 599 >19.6
w1 4126 5762 393 >20.1
The magnitudes in the table are not corrected for the Galactic
extinction due to the reddening of E(B-V) = 0.02 in the direction of the
burst (Schlegel et al. 1998).
GCN Circular 20178
Subject
GRB 161113A: Swift-BAT refined analysis
Date
2016-11-15T14:49:29Z (9 years ago)
From
Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>
S. D. Barthelmy (GSFC), J. R. Cummings (GSFC/UMBC), P. D'Avanzo (INAF-OAB),
N. Gehrels (GSFC), H. A. Krimm (NSF/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+499 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 161113A (trigger #722063)
(D'Avanzo, et al., GCN Circ. 20172). The BAT ground-calculated position is
RA, Dec = 179.794, -5.316 deg which is
RA(J2000) = 11h 59m 10.6s
Dec(J2000) = -05d 18' 57.3"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve shows a pair of overlapping peaks, both containing
substructure. The first peak begins at T-3 sec and peaks at T+5 sec. The second
peaks at T+15 sec and continues until about T+60 sec.
T90 (15-350 keV) is 42.60 +- 11.10 sec (estimated error including systematics).
The time-averaged spectrum from T+0.12 to T+64.88 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.73 +- 0.10. The fluence in the 15-150 keV band is 1.5 +- 0.1 x 10^-6 erg/cm2.
The 1-sec peak photon flux measured from T+15.28 sec in the 15-150 keV band
is 1.4 +- 0.2 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/722063/BA/