GRB 160131A
GCN Circular 19206
Subject
GRB 160131A: 15 GHz upper limits from AMI-LA
Date
2016-03-17T19:13:30Z (10 years ago)
From
Kunal Mooley at Oxford U <kunal.mooley@physics.ox.ac.uk>
K. P. Mooley, R. P. Fender, T. D. Staley (Oxford), G. Ghirlanda, F.
Nappo (INAF, Merate), C. Rumsey, D. Titterington, S. Carey, J. Hickish,
Y. C. Perrott, N. Razavi-Ghods, P. Scott (Cambridge), K. Grainge, A.
Scaife (Manchester)
We observed the XRT position of GRB 160131A discovered by Swift (Page et
al., GCN 18951; Goad et al., GCN 18958) at 15 GHz with the Arcminute
Microkelvin Imager (AMI-LA) on 2016 Feb 24.79 UT and Mar 06.79 UT,
corresponding to 24.5 days and 34.5 days post-burst respectively. We do
not detect any radio source at the XRT location, with 3sigma upper
limits of 150 uJy and 210 uJy respectively.
We thank the AMI scheduling team for carrying out these observations.
GCN Circular 19011
Subject
GRB160131A: detection of polarisation by Astrosat CZTI
Date
2016-02-12T13:23:06Z (10 years ago)
From
Dipankar Bhattacharya at IUCAA <dipankar@iucaa.in>
S. V. Vadawale (PRL), T. Chattopadhyay (PRL), N. P. S. Mithun (PRL),
A. R. Rao (TIFR), D. Bhattacharya (IUCAA), Varun Bhalerao (IUCAA)
report on behalf of the Astrosat CZTI collaboration:
Astrosat CZT Imager detected GRB 160131A (Page and Barthelmy, GCN 18951)
at an incident angle of 63 degrees from the telescope pointing axis.
The T90 was measured to be 106 s and 97 s in 30 - 100 keV and 100 - 300
keV respectively. CZTI being sensitive to polarimetry [Chattopadhyay et
al, 2014, EXPA, Vadawale et al 2015, A&A], we have analysed the double
events due to Compton scattering and detect a clear azimuthal modulation
of 0.30 +/- 0.12 %, with a detection significance of 2.5 sigma. Based on a
preliminary mass modelling, we estimate that the source polarisation
fraction lies between ~ 50 - 60 % in 100-300 keV band. A detailed mass
modeling to refine this measurement and its estimated uncertainty is in
progress. In an earlier event, GRB 151006A (Bhalerao et al. GCN 18422)
CZT Imager data showed a marginal evidence for polarisation signal. From
the higher detection confidence for this brighter GRB160131A, we estimate
that CZT Imager can provide time resolved spectro-polarimetry for GRBs
with fluence larger than 10^-4 erg per cm^2.
This message may be cited.
GCN Circular 19010
Subject
GRB 160131A: second epoch observations with the GMRT
Date
2016-02-11T10:00:38Z (10 years ago)
From
Poonam Chandra at TIFR <poonam@ncra.tifr.res.in>
Poonam Chandra (NCRA-TIFR) and A. J. Nayana (NCRA-TIFR) report on
behalf of a
larger collaboration:
We reobserved GRB 160131A (GCN Circ. 18951) with the Giant Metrewave Radio
Telescope (GMRT) at 1420 MHz band on 2016 Feb 10.78 UT. While we do not
detect
the GRB radio afterglow, we place very constraining 3-sigma upper limit
on the
GRB flux in the Swift error cicle (GCN Circ. 18970) to be 105 uJy.
The GMRT data for GRB 160131A is public for anyone to use.
Further observations are planned. We thank GMRT staff for making these
observations possible.
--
_________________________________________
Poonam Chandra
National Centre for Radio Astrophysics
Tata Institute of Fundamental Research
Pune University Campus, Ganeshkhind
Pune 411007, Maharashtra, INDIA
Phone: +91 20 2571 9290
Fax: +91 20 2569 7257
Email: poonam@ncra.tifr.res.in
Web: www.ncra.tifr.res.in:8081/~poonam/
_________________________________________
GCN Circular 19009
Subject
Low frequency GMRT observations of GRB 160131A
Date
2016-02-10T10:15:28Z (10 years ago)
From
Poonam Chandra at TIFR <poonam@ncra.tifr.res.in>
Poonam Chandra (NCRA-TIFR) and A. J. Nayana (NCRA-TIFR) report on
behalf of a
larger collaboration:
We carried out the Giant Metrewave Radio Telescope (GMRT) observations of
GRB 160131A (GCN Circ. 18951) at 1280 and 610 MHz band on 2016 Feb 09.61
UT.
The data is badly affected by RFI and hence we could not obtain the
expected rms.
The 3-sigma upper limit on the GRB flux in the Swift error cicle (GCN
Circ. 18970)
are 570 and 382 uJy in 1280 and 610 MHz bands, respectively.
The GMRT data for GRB 160131A is public for anyone to use.
Further observations are planned. We thank GMRT staff for making these
observations possible.
GCN Circular 19004
Subject
GRB 160131A: TSHAO optical observations
Date
2016-02-08T22:04:39Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Volnova
(IKI), A. Kusakin (Fesenkov Astrophysical Institute), A. Pozanenko
(IKI) report on behalf of larger GRB follow-up collaboration:
We observed the Swift GRB 160131A (Page et al., GCN 18951) with
Zeiss-1000 (East) 1-m telescope of Tien Shan Astronomical Observatory.
We obtained several images in R filter on Feb. 06 and Feb. 07.The
optical afterglow (Page et al., GCN 18951; Yurkov et al., GCN 18952;
Guidorzi et al., GCN 18953; Xin et al., GCN 18954; Xin et al., GCN
18955; Watson et al., GCN 18956) is detected on Feb. 06 and not detected
on Feb. 07. Preliminary photometry is following
Date UT start t-T0 Filter Exp. OT Err.
(mid, days) (s)
2016-02-06 13:45:54 6.26762 R 21*300 22.40 0.3
2016-02-07 13:30:04 7.25330 R 21*300 >22.40 (3sigma)
Photometry is based on nearby USNO-B1.0 stars
USNO-B.1_id R2
0829-0078223 15.70
0829-0078147 14.56
0829-0078167 17.71
0829-0078222 18.96
0829-0078226 18.69
0829-0078129 17.62
GCN Circular 18992
Subject
GRB 160131A: TSHAO optical observations
Date
2016-02-05T18:49:47Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Volnova
(IKI), A. Kusakin (Fesenkov Astrophysical Institute), A. Pozanenko
(IKI) report on behalf of larger GRB follow-up collaboration:
We observed the Swift GRB 160131A (Page et al., GCN 18951) with
Zeiss-1000 (East) 1-m telescope of Tien Shan Astronomical Observatory
starting on Feb. 05 (UT) 14:22:45. We obtained several images in R
filter. We clearly detect optical afterglow (Page et al., GCN 18951;
Yurkov et al., GCN 18952; Guidorzi et al., GCN 18953; Xin et al., GCN
18954; Xin et al., GCN 18955; Watson et al., GCN 18956) in a combined
image. Preliminary photometry is following
Date UT start t-T0 Filter Exp. OT Err.
(mid, days) (s)
2016-02-05 14:22:45 5.28802 R 21*300 22.40 0.20
Photometry is based on nearby USNO-B1.0 stars
USNO-B.1_id R2
0829-0078223 15.70
0829-0078147 14.56
0829-0078167 17.71
0829-0078222 18.96
0829-0078226 18.69
0829-0078129 17.62
GCN Circular 18991
Subject
GRB 160131A: Mondy optcial observations
Date
2016-02-05T15:15:24Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (IKI), E. Mazaeva (IKI), E. Klunko (ISTP), I. Korobtsev
(ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up
collaboration:
We observed the Swift GRB 160131A (Page et al., GCN 18951) with AZT-33IK
telescope of Sayan observatory (Mondy) starting on Feb.04 (UT)
11:42:43. We detect optical afterglow (Page et al., GCN 18951; Yurkov et
al., GCN 18952; Guidorzi et al., GCN 18953; Xin et al., GCN 18954; Xin
et al., GCN 18955; Watson et al., GCN 18956) in a combined image.
Preliminary photometry is following
Date UT start t-T0 Filter Exp. OT Err.
(mid, days) (s)
2016-02-04 11:42:43 4.16058 R 29*120 21.70 0.23
USNO-B.1_id R2
0829-0078147 14.56
0829-0078222 18.96
0829-0078226 18.69
0829-0078129 17.62
GCN Circular 18988
Subject
GRB 160131A: RATIR Optical Observations
Date
2016-02-04T16:54:53Z (10 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 (GSFC/STScI),
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 160131A (Page, et al., GCN 18951) 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 2016/02 4.10 to 2016/02 4.36 UTC (89.96 to
96.25 hours after the BAT trigger), obtaining a total of 4.60 hours
exposure in the r, i, and z bands.
For a source within the Swift-XRT error circle (Osborne, et al., GCN
18958), in comparison with the USNO-B1 and 2MASS catalogs, we obtain the
following detections and upper limit (3-sigma):
r = 21.64 +/- 0.05
i = 21.41 +/- 0.03
z > 20.48
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. We note that there is a faint,
possible source present in the DSS near this source which could be the GRB
host galaxy.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 18978
Subject
GRB 160131A: correction to VLA position
Date
2016-02-02T22:20:06Z (10 years ago)
From
Tanmoy Laskar at UC Berkeley <tanmoylaskar@gmail.com>
T. Laskar (NRAO / UC Berkeley) reports:
"Our original circular (Laskar et al.; GCN 18977) contained a typo in the
right ascension of the radio source. The correct position is
RA = 05:12:40.351 +/- 0.001
Dec = -07:02:58.80 +/- 0.02
Thanks to Frank Marshall for pointing out the error."
GCN Circular 18977
Subject
GRB 160131A: VLA detection
Date
2016-02-02T21:22:19Z (10 years ago)
From
Tanmoy Laskar at UC Berkeley <tanmoylaskar@gmail.com>
T. Laskar (NRAO / UC Berkeley), K. D. Alexander, and E. Berger (Harvard)
report on behalf of a larger collaboration:
"We observed GRB 160131A (Page & Barthelmy; GCN 18951) at multiple
frequencies with the Karl G. Jansky Very Large Array (VLA) beginning on
2016 February 01.11 UT (0.76 days after the burst). At a mean frequency of
21.8 GHz, we detect a radio source with a preliminary flux density of ~
0.53 mJy at
RA = 15:12:40.351 +/- 0.001
Dec = -07:02:58.80 +/- 0.02
consistent with the enhanced Swift/XRT position (Goad et al.; GCN 18958)
and the optical position (Page & Barthelmy.; GCN 18951, Yurkov et al.; GCN
18952). Follow-up observations are planned. We thank the VLA staff for
rapidly scheduling these observations."
GCN Circular 18976
Subject
GRB160131A: NOEMA detection of the millimetre afterglow
Date
2016-02-02T17:25:19Z (10 years ago)
From
Steve Schulze at U of Iceland <sts30@hi.is>
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), S. Schulze (PUC, MAS), M. Bremer (IRAM), S. Mart��n (JAO), J. M. Winters (IRAM) report on behalf a larger collaboration:
We conduced millimetre observations of GRB160131A (Page et al., GCN 18951) with the NOrthern Extended Millimeter Array (NOEMA; Plateau de Bure, France) at 93 and 150 GHz. Observations started at 17:05 UT on February 1 (i.e. 1.36 days after the burst).
We clearly detect the afterglow at both frequencies. A preliminary analysis of the 93 GHz data reveals a flux density of 1.94 +/- 0.07 mJy. Further observations are scheduled.
We encourage follow-up observations at all frequencies.
GCN Circular 18974
Subject
Konus-Wind observation of GRB 160131A
Date
2016-02-02T15:36:05Z (10 years ago)
From
Anastasia Tsvetkova at Ioffe Institute <tsvetkova@mail.ioffe.ru>
A. Tsvetkova, S. Golenetskii, R.Aptekar, D. Frederiks, P. Oleynik,
M. Ulanov, D. Svinkin, A. Lysenko, A. Kozlova and T. Cline
on behalf of the Konus-Wind team, report:
The long-duration, extremely hard-spectrum GRB 160131A
(Swift-BAT trigger #672236: Page & Barthelmy, GCN 18951;
Cummings et al., GCN 18959)
triggered Konus-Wind at T0=30044.577 s UT (08:20:44.577).
The burst light curve shows a single, FRED-like pulse
with a total duration (80-1400 keV) of ~200 s.
In the softest KW energy band the emission can be traced up to ~300 s.
The emission is seen up to ~15 MeV.
As observed by Konus-Wind, the burst
had a fluence of 3.26(-0.32,+0.31)x10^-4 erg/cm2,
and a 64-ms peak energy flux, measured from T0+2.704 s,
of 2.23(-0.46,+0.46)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum of the burst
(measured from T0 to T0+162.048 s)
is best fit in the 20 keV - 15 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.97(-0.15,+0.24),
the high energy photon index beta = -1.56(-0.10,+0.07),
the peak energy Ep = 586(-259,+518) keV,
chi2 = 98/97 dof.
The spectrum near the peak count rate
(measured from T0+0.256 to T0+14.592 s)
is best fit in the 20 keV - 15 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.94(-0.18,+0.13),
the high energy photon index beta = -1.56(-0.56,+0.06),
the peak energy Ep = 1152(-438,+3060) keV,
chi2 = 135/97 dof.
Assuming the redshift z=0.972 (Malesani et al., GCN 18965;
de Ugarte Postigo, Thoene & Sanchez-Ramirez, GCN 18966;
Xu, Xin & Wang, GCN 18969)
and a standard cosmology model with H_0 = 70 km/s/Mpc,
Omega_M = 0.27, and Omega_Lambda = 0.73,
we estimate the following rest-frame parameters:
the isotropic energy release E_iso is ~8.3x10^53 erg,
the peak luminosity L_iso is ~1.1x10^53 erg/s,
and the rest-frame peak energy of the time-integrated spectrum,
Ep,i, is ~1150 keV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160131_T30044/
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
GCN Circular 18973
Subject
GRB 160131A: Optical observations from T150 OSN
Date
2016-02-02T15:12:35Z (10 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), C.C. Thoene (IAA-CSIC),
V. Casanova (IAA-CSIC) and F. Aceituno (IAA-CSIC) report:
We observed the afterglow of GRB 160131A (Page et al. GCN 18951)
from the 1.5m telescope (T150), at Sierra Nevada Observatory (Granada,
Spain) in two epochs on the first and second night after the GRB.
In the first epoch we performed observations in the V, R and I filters
and the object is well detected in all bands. During these observations
on January 31.807 (10.8 hr after the burst), the object has a magnitude of
R=17.90+/-0.02 (Vega), using as reference star the same
USNO-B1.0 object mentioned in the circular by Xin et al. (GCN 18954).
On the second night we performed photometry in 5 bands, U, B, V, R
and I, the object is again detected in all bands. In an image with mean
epoch February 1.835 (35.5 hr after the burst) we detect the object at
R=19.83+/-0.03.
GCN Circular 18972
Subject
GRB 160131A: AbAO optical observations
Date
2016-02-01T20:28:41Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), R. Inasaridze (AbAO), V. Ayvazian (AbAO), A. Volnova
(IKI), I. Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger
GRB follow-up collaboration:
We observed the field of Swift GRB 160131A (Page et al., GCN 18951) with
AS-32 (0.7m) telescope of Abastumani Observatory starting on Jan. 31
(UT) 19:16:57. We obtained several unfiltered images of 120 s exposure.
We detect optical afterglow (Page et al., GCN 18951; Yurkov et al., GCN
18952; Guidorzi et al., GCN 18953; Xin et al., GCN 18954; Xin et al.,
GCN 18955; Watson et al., GCN 18956). Preliminary light curve can be
found in http://grb.rssi.ru/GRB160131A/GRB160131A_20160131_AbAO_lc.png
The photometry is base on nearby USNO-B1.0 stars:
USNO-B.1_id R2
0829-0078223 15.70
0829-0078147 14.56
0828-0074893 14.88
0828-0074768 14.81
GCN Circular 18971
Subject
GRB 160131A: Mondy optical observations
Date
2016-02-01T19:53:38Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), E. Klunko (ISTP), A. Volnova (IKI), I. Korobtsev
(ISTP), A. Pozanenko (IKI) report on behalf of larger GRB follow-up
collaboration:
We observed the Swift GRB 160131A (Page et al., GCN 18951) with AZT-33IK
telescope of Sayan observatory (Mondy) starting on Feb.01 (UT)
13:01:56. We clearly detect optical afterglow (Page et al., GCN 18951;
Yurkov et al., GCN 18952; Guidorzi et al., GCN 18953; Xin et al., GCN
18954; Xin et al., GCN 18955; Watson et al., GCN 18956). Preliminary
photometry of the afterglow of the first image is following
Date UT start t-T0 Filter Exp. OT Err.
(mid, days) (s)
2016-02-01 13:01:56 1.19543 R 1*120 19.40 0.08
GCN Circular 18970
Subject
GRB 160131A Swift/UVOT Detection
Date
2016-02-01T18:09:05Z (10 years ago)
From
Marissa McCaule at PSU <marissamc@swift.psu.edu>
L. M. McCauley (PSU), K. L. Page (U Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160131A
78 s after the BAT trigger (Page et al., GCN Circ. 18951).
A fading source consistent with the XRT position (Beardmore et al. GCN
Circ. 18159)
is detected in the initial UVOT exposures.
The preliminary UVOT position is:
RA (J2000) = 05:12:40.33 = 78.16804 (deg.)
Dec (J2000) = -07:02:58.81 = -7.04967 (deg.)
with an estimated uncertainty of 0.43 arc sec. (radius, 90% confidence).
Preliminary detections and 3-sigma upper limits using the UVOT photometric
system (Breeveld et al. 2011, AIP Conf. Proc. 1358, 373) for the early
exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_fc 78 228 147 13.77+-1.10
white 5051 11361 1081 16.71+-0.02
v 4026 5662 393 15.72+-0.03
b 4846 10449 1138 16.81+-0.02
u 290 540 245 13.08+-0.03
u 4641 6277 393 15.64+-0.03
uvw1 4436 6072 393 16.18+-0.04
uvm2 4231 5867 393 16.64+-0.06
uvw2 3821 12083 1098 17.43+-0.05
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.11 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 18969
Subject
GRB 160131A: Xinglong/BFOSC spectroscopy
Date
2016-02-01T03:38:02Z (10 years ago)
From
Dong Xu at NAOC/CAS <dxu@nao.cas.cn>
D. Xu, L.-P. Xin, J. Wang (NAOC/CAS) report on behalf of a larger
collaboration:
We observed the optical afterglow of GRB 160131A (e.g., Page et al., GCN
18951; Yurkov et al., GCN 18952; Guidorzi et al., GCN 18953; Xin et al.,
GCN 18954) using the 2.16m telescope located at Xinglong, Heibei, China,
equipped with the BFOSC camera. A 2400s spectrum was acquired with the
G4+385LP grism covering the range of 3500 - 8500 AA, starting at
13:49:08 UT on 2016-01-31.
The spectrum shows a continuum across the whole range, superimposed with
absorption features of Mg II, Ca II H+K at a common redshift of 0.97,
being consistent with measurements by Malesani et al. (GCN 18965