GRB 160310A
GCN Circular 19210
Subject
GRB 160310A: Terskol 2-m observations
Date
2016-03-21T07:40:35Z (10 years ago)
From
Moskvitin Alexander at SAO RAS <mosk@sao.ru>
Ilia V. Sokolov (Terskol Peak Observatory), M. Andreev (Terskol Peak
Observatory), A. Sergeev (Terskol Peak Observatory),
A. Moskvitin (SAO RAS) report:
We observed the GRB160310A field 17h 57m 26s after the trigger (Fermi
trigger number 479262182) in R-band with a total exposure of 13 x 120 s.
We detected a source brighter than in SDSS images at
RA = 06:35:14.4
Dec = -07:03:49.0
with the R magnitude 20.34. The magnitude is not corrected
for the Galactic extinction due to the reddening of E(B-V) = 0.53
in the direction of the burst (Schlegel et al. 1998).
The photometry is based on USNO-b1 stars.
GCN Circular 19209
Subject
IPN Triangulation of GRB 160310A
Date
2016-03-19T21:42:04Z (10 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,
K. Hurley, on behalf of the IPN,
V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa,
and A. Goldstein, on behalf of the Fermi GBM team, and
S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team, report:
The long-duration GRB 160310A was detected by Konus-Wind (Frederiks et
al., GCN Circ. 19167), Fermi (LAT: Vianello et al., GCN Circ. 19158 and
GBM: Toelge & Hui GCN Circ. 19167), and Swift (BAT), at about 1378 s UT
(00:22:58). The burst was outside the coded field of view of the BAT.
We have triangulated it to a Konus-GBM annulus centered at
RA(2000)=178.455 deg (11h 53m 49s) Dec(2000)=-2.131 deg (-2d 07' 52"),
whose radius is 76.571 +/- 0.876 deg (3 sigma) and to a Konus-BAT
annulus centered at RA(2000)=178.592 deg (11h 54m 22s) Dec(2000)=-2.265
deg (-2d 15' 53"), whose radius is 76.187 +/- 1.716 deg (3 sigma).
While the GBM position is in a good agreement with both the Konus-GBM
and the Konus-BAT annuli, the LAT position reported in GCN 19158 is 2.9
deg (~10 sigma) from the Konus-GBM annulus center line. So we encourage
further investigation of the LAT position.
Using the method suggested by Pal'shin, et al., ApJS 207, 38, 2013 (sec.
4.2.1) and assuming a LAT error radius of 6 deg, we obtain the following
joint LAT/IPN error box:
--------------------------------
RA(2000), deg Dec(2000), deg
--------------------------------
Center:
101.726 -7.1445
Corners:
100.850 -13.082
102.648 -13.076
102.726 -1.228
100.975 -1.191
---------------------------------
The error box area is 21 sq. deg, and its maximum
dimension is 12 deg (the minimum one is 1.8 deg).
A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB160310_T01391/IPN/
GCN Circular 19205
Subject
GRB 160310A: A further Swift-XRT observation, no afterglow detected
Date
2016-03-17T15:50:36Z (10 years ago)
From
Alessandro Maselli at INAF/IASF Palermo <maselli@ifc.inaf.it>
A. Maselli (INAF-IASFPA) and P. A. Evans (U. Leicester) report on behalf
of the Swift-XRT team:
On 2016 March 16, Swift-XRT has carried out a further observation of the
field of GRB 160310A detected by Fermi (Vianello et al., GCN Circ.
19158; Toelge and Hui, GCN Circ. 19161), collecting 4.0 ks of data from
T0+569 ks to T0+599 ks. The X-ray source reported by Gibson et al. (GCN
Circ. 19162) is still detected with a count rate of (5.5+/-1.8)E-03
ct/s, showing no evidence of fading. Therefore, this source is not
related to the GRB. The 3-sigma upper limit for the observation carried
out between T0+40.3 ks and T0+46.7 ks, computed at the center of the
Fermi-LAT error circle, is 3.8E-03 ct/s. We conclude that no afterglow
has been identified by Swift-XRT for GRB 160310A.
This circular is an official product of the Swift-XRT team.
GCN Circular 19170
Subject
GRB 160310A: MASTER-Kislovods observations
Date
2016-03-12T18:06:02Z (10 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
E. Gorbovskoy, V. Lipunov, N.Tyurina, V.Kornilov,
P.Balanutsa, A.Kuznetsov, D.Kuvshinov
Lomonosov Moscow State University,
Sternberg Astronomical Institute, Moscow State University
A. Tlatov, V.Senik, A.V. Parhomenko, D. Dormidontov
Kislovodsk Solar Station of the Pulkovo Observatory
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Kislovodsk was pointed to the GRB160310.02 23 sec after notice
time and 56663 sec after trigger time at 2016-03-10 16:07:21 UT. We not
found optical transient around and inside LAT
error-box (ra=06 35 05 dec=-07 06 34 r=1 degree) brighter then 19.0 .
The message may be cited.
GCN Circular 19169
Subject
GRB 160310A: Further NOT observations
Date
2016-03-12T15:01:05Z (10 years ago)
From
Thomas Kruehler at MPE Garching <kruehler@mpe.mpg.de>
T. Kruehler (MPE Garching), G. Leloudas (Weizmann Institute, DARK/NBI),
D. Malesani (DARK/NBI), and T. Kuutma (NOT) report on behalf of a
larger collaboration:
We again observed the field of GRB 160310A (Vianello et al., GCN #19158,
Toelge & Hui, GCN #19161) with the NOT equipped with ALFOSC.
A second epoch of imaging in the I-band filter was obtained starting at
20:21:05 UT on 2016-03-11, 48.0 hr after the GRB trigger.
In a combined image of 5x120 s exposure time, we still detect
the same source in the XRT error circle at a brightness comparable to
the observations 24 hours earlier (Kruehler et al., GCN #19164, see
also Troja et al., GCN #19166), indicating that it is likely not the
optical afterglow of GRB 160310A.
GCN Circular 19168
Subject
GRB 160310A: Swift/UVOT Upper Limits
Date
2016-03-11T22:47:55Z (10 years ago)
From
Frank Marshall at GSFC <femarsha@khamseen.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC) and A. Maselli (INAF/IASF)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160310A
40247 s after the LAT trigger (Vianello et al., GCN Circ. 19158).
No source is detected in the initial UVOT exposures
at a position consistent with the position
of the possible XRT afterglow (Gibson et al., GCN Circ. 19162)
or the possible optical counterpart (Kruehler et al., GCN Circ. 19164).
Preliminary 3-sigma upper limits using the UVOT photometric system
(Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the initial exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
u 40247 46726 1273 >20.4
white 41072 41890 805 >21.3
v 41897 42757 843 >19.9
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.53 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 19167
Subject
Konus-Wind observation of GRB 160310A (possible ultra-long GRB?)
Date
2016-03-11T17:33:47Z (10 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov,
D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline,
on behalf of the Konus-Wind team, report:
The long GRB 160310A (Fermi/LAT detection: Vianello et al., GCN 19158;
Fermi/GBM detection: Toelge & Hui, GCN 19161)
triggered Konus-Wind at T0=1391.997 s UT (00:23:11.997).
The light curve shows a multi-peaked pulse which started
at ~T0-14 s and lasted until ~T0+15 s (the total duration is ~30 s).
The emission is seen up to ~4 MeV.
As observed by Konus-Wind, the burst had a fluence of
(6.8 �� 1.5)x10^-6 erg/cm2 and a 64-ms peak energy flux,
measured from T0-0.192, of (2.1 �� 0.4)x10^-6 erg/cm2
(both in the 20 keV - 10 MeV energy range).
The spectrum of the burst (measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 10 MeV range by a cutoff power-law
(CPL) function with the following model parameters:
the photon index alpha = -1.40(-0.16,+0.21),
and the peak energy Ep = 316(-95,+206) keV,
chi2 = 89/85 dof.
Fitting this spectrum with the GRB (Band) function yields
the same alpha and Ep with only an upper limit on beta of -2.0,
chi2 = 89/94 dof.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160310_T01391/
In the KW waiting mode data, GRB 160310A was preceded by
a weaker, GRB-like event lasting from ~T0-1510 s to ~T0-1418 s
(the total duration is ~90 s).
Modeling the KW 3-channel spectrum for this episode
by the CPL function yields alpha = -1.23 �� 0.24, Ep = 142 �� 57 keV,
and a 20--1500 keV fluence of (7.7 �� 1.7)x10^-6 erg/cm2.
The KW ecliptic latitude response for this event is consistent
with that for GRB 160310A. Taking this into account,
we suggest a possibility that GRB 160310A is, in fact,
a double-episode, ultra-long GRB with a total duration of ~1500 s.
All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.
GCN Circular 19166
Subject
GRB 160310A: RATIR Optical and NIR Observations
Date
2016-03-11T14:05:14Z (10 years ago)
From
Eleonora Troja at GSFC <eleonora.troja@nasa.gov>
Eleonora Troja (GSFC), 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 (GSFC/STScI), 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 the Fermi GRB 160310A (Vianello, et al., GCN
19158; Toelge, et al., GCN 19161) 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 2016/03 11.16 to 2016/03 11.32 UTC (27.46 to 31.25 hours
after the GBM trigger).
We observed the two uncatalogued X-ray sources detected by the Swift/XRT
(Gibson, et al., 19162). For source #1 we obtained a total of 1.07 hours
exposure in the r and i bands and 0.45 hours exposure in the J, and H
bands. For a source within the XRT error circle, in comparison with the
USNO-B1 and 2MASS catalogs, we obtain the following detections:
r 19.89 +/- 0.02
i 19.34 +/- 0.01
J 18.03 +/- 0.01
H 17.37 +/- 0.01
These values are consistent with the magnitudes of a USNO-B1 catalogued
object. No other source is visible within the XRT localization.
For source#2 we obtained a total of 1.78 hours exposure in the r and i
bands and 0.75 hours exposure in the J, and H bands. For a source within
the XRT error circle, in comparison with the USNO-B1 and 2MASS catalogs,
we obtain the following detections:
r 22.48 +/- 0.09
i 21.82 +/- 0.05
J 20.62 +/- 0.10
H 20.03 +/- 0.08
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. Our values are slightly fainter
than the NOT detection (Kruehler, et al., GCN 19164), although no strong
claim about variability can be made at this time. Further observations
to determine the nature of source #2 are encouraged.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 19164
Subject
GRB 160310A: NOT optical observations
Date
2016-03-10T21:55:00Z (10 years ago)
From
Thomas Kruehler at MPE Garching <kruehler@mpe.mpg.de>
T. Kruehler (MPE Garching), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI),
D. Malesani (DARK/NBI), and T. Kuutma (NOT) report on behalf of a
larger collaboration:
We observed the field of GRB 160310A (Vianello et al., GCN #19158,
Toelge & Hui, GCN #19161) with the NOT equipped with ALFOSC.
Imaging in the i-band filter started at 20:40:57 UT on
2016-03-10, 20.3 hr after the GRB trigger.
In a combined image of 5x120 s exposure time, we detect a single
source in the XRT error circle (Gibson et al. GCN#19162) at a
position of
RA (J2000.0) = 06:35:17.33
Dec. (J2000.0) = -07:12:56.0
with an uncertainty of 0".5 in each coordinate.
Calibrating our image against I-band magnitudes from field stars
of the USNO-B1 catalog, we measure a preliminary brightness of
I = 21.4 +- 0.2 mag
not corrected for the expected foreground extinction corresponding
to a reddening of E_B-V = 0.486 mag (Schlafly & Finkbeiner 2011)
The field is relatively crowded, and chance coincidences in the 5.1"
error circle are not unlikely. No statement about possible variability
can be made at this point.
GCN Circular 19163
Subject
GRB 160310A: LCOGT-SAAO optical upper limits
Date
2016-03-10T19:53:37Z (10 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
D. Xu (NAOC/CAS) reports on behalf of a collaboration:
We observed the field of GRB 160310A (Vianello et al., GCN 19158) using
the LCOGT 1-m located at Sutherland, South Africa. Observations started
at 18:57:18 UT on 2016-03-10 (i.e., 18.75 hr after the burst) and 2x300s
frames were obtained in R- and I-band each.
No credible source is detected within or at the edge of the error circle
of the XRT Source 2 reported in Gibson et al. (GCN 19162), down to
limiting magnitudes of R~20.0 and I~18.6, respectively.
[GCN OPS NOTE(10mar16): Per author's request, "SSO" was changed to "SAAO".]
GCN Circular 19162
Subject
GRB 160310A: Swift-XRT observations
Date
2016-03-10T18:58:39Z (10 years ago)
From
Alessandro Maselli at INAF/IASF Palermo <maselli@ifc.inaf.it>
S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai
(INAF-IASFPA), T.G.R. Roegiers (PSU), L.M. McCauley (PSU), J.A. Kennea
(PSU) and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT
team:
Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 160310A (Vianello et al. GCN Circ. 19158),
collecting 3.0 ks of Photon Counting (PC) mode data between T0+40.3 ks
and T0+46.7 ks.
One uncatalogued X-ray source has been detected inside or close to the
Fermi/LAT error region, it is below the RASS limit and shows no
definitive signs of fading. Therefore, at the present time we cannot
confirm this as the afterglow. Details of this source are given below:
Source 2:
RA (J2000.0): 98.8226 = 06:35:17.42
Dec (J2000.0): -7.2156 = -07:12:56.1
Error: 5.1 arcsec (radius, 90% conf.)
Count-rate: (5.2 +/- 1.9)e-3 ct s^-1
Flux: (1.18 +/- 0.43)e-13 erg cm^-2 s^-1 (observed, 0.3-10 keV)
Another uncatalogued was also detected, however this was too far from
the GRB position to be the afterglow.
The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
http://www.swift.ac.uk/ToO_GRBs/00020602.
This circular is an official product of the Swift-XRT team.
GCN Circular 19161
Subject
GRB 160310A: Fermi GBM observation
Date
2016-03-10T15:30:33Z (10 years ago)
From
Kilian Toelge at MPE <tkili@mpe.mpg.de>
Kilian Toelge (MPE) and Michelle Hui (UAH)
report on behalf of the Fermi GBM Team:
"At 00:22:58.47 UT on 10 March 2016, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 160310A (trigger 479262182 / 160310016),
which was also detected by the LAT
(G.Vianello et al. 2016, GCN 19158)
The GBM on-ground location is consistent with the LAT position.
The angle from the Fermi LAT boresight at the GBM trigger time is 68
degrees.
The GBM light curve shows/consists of five pulses
with a duration (T90) of about 18.2 s (50-300 keV).
The time-averaged spectrum from T0-0.5 s to T0+20.0 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.1 +/- 0.1 and
the cutoff energy, parameterized as Epeak, is 129.0 +/- 9.5 keV.
The event fluence (10-1000 keV) in this time interval is
(4.8 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+11.8 s in the 10-1000 keV band
is 7.1 +/- 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 19159
Subject
GRB 160310A: Swift ToO observations
Date
2016-03-10T11:39:20Z (10 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the Fermi/LAT GRB 160310A.
Automated analysis of the XRT data will be presented online at
http://www.swift.ac.uk/ToO_GRBs/00020602
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the Fermi/LAT event. 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; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
GCN Circular 19158
Subject
GRB 160310A: Fermi-LAT detection
Date
2016-03-10T10:12:10Z (10 years ago)
From
Giacomo Vianello at SLAC <giacomov@slac.stanford.edu>
G.Vianello (Stanford), M. Yassine (CNRS/IN2P3), E.Moretti (MPP Munich)
report on behalf of the Fermi-LAT team:
At 00:22:58.47 on March, 10, 2016 (T0) Fermi-LAT detected high-energy
emission from GRB 160310A, which was also detected by Fermi-GBM
(trigger 479262181 / 160310016).
The best LAT on-ground location is found to be
RA, Dec = 98.78, -7.11 (J2000)
with an error radius of 0.1 deg (90 % containment, statistical error only).
This was 62 deg from the LAT boresight at the time of the trigger, on
the edge of the field of view.
The data from the Fermi-LAT show a significant increase in the event
rate that is spatially and temporally correlated with the trigger with
high significance.
At the time of the trigger Fermi was in normal survey mode. The GRB
was observable by Fermi from T0 to ~T0 + 500 s, and then again from
~T0 + 5200 s and T0 + 7000 s. The highest-energy photon is a 30 GeV
event which is observed 5800 seconds after the GBM trigger.
A Swift ToO has been requested for this burst.
The Fermi-LAT point of contact for this burst is Giacomo Vianello
(giacomov@stanford.edu).
The Fermi-LAT is a pair conversion telescope designed to cover the
energy band from 20 MeV to greater than 300 GeV. It is the product of
an international collaboration between NASA and DOE in the U.S. and
many scientific institutions across France, Italy, Japan and Sweden.