GRB 160303A
GCN Circular 19160
Subject
GRB 160303A: GTC imaging of possible host galaxy
Date
2016-03-10T13:38:32Z (10 years ago)
From
Zach Cano at U of Iceland <zewcano@gmail.com>
���Z. Cano (U. Iceland), A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D.
Malesani (DARK/NBI) and C. C. Thoene (IAA-CSIC) report on behalf of a
larger collaboration:
We observed the field of GRB 160303A (Beardmore et al., GCN Circ. 19126)
with the 10.4-m GTC telescope (OSIRIS instrument) on 2016 March 8.15 UT
(+4.7 days) in SDSS filters r and i. The optical transient associated with
this event (Butler et al., GCN Circ. 19131) is no longer detected.
Instead, we note the presence of a nearby, extended source with an r-band
(AB) magnitude of 25.8 +- 0.3, as calibrated using nearby SDSS stars.
After registering the astrometry of the GTC images against our NOT
afterglow image (de Ugarte Postigo et al., GCN Circ. 19136), we find that
the centroid of the extended object is offset by 1.7'' +- 0.3'' in the
North-East direction. We note that the radial extent of this object nearly
reaches the position of the previously detected optical transient. Using
the equations from Bloom, Kulkarni & Djorgovski (2002, AJ, 123, 1111), we
calculate that the chance probability of finding an object with r = 25.8 at
a separation of 1.7'' is 14% -- small, but not negligible.
If the extended object is associated with GRB 160303A, then for a standard
cosmology this angular separation corresponds to 3.2, 5.6, 7.6, 10.5 kpc
for redshifts of z=0.1, 0.2, 0.3, 0.5, respectively. This offset is
consistent with that measured for short-duration GRBs at z=0.2 (median
offset = 5 kpc for a range of 0.5-75 kpc; Fong, Berger & Fox 2010, ApJ,
708, 9). Instead, if GRB 160303A is a long-duration GRB, for this offset
to be consistent with those measured for LGRBs (1 kpc, Bloom, Kulkarni &
Djorgovski 2002, AJ, 123, 1111; de Ugarte Postigo et al. 2012, A&A, 548,
11), it would require a redshift of z=0.03. The luminosity distance at
this redshift implies an absolute magnitude of M_r=-9.8, which is roughly
eight to ten magnitudes fainter than those measured for LGRB host galaxies
in sample studies (Savaglio, Glazebrook & Le Borgne, ApJ, 691, 182;
Kruehler et al. 2015, A&A, 581, 125). Based on this line of argument, this
observation suggests that GRB 160303A may be a short-duration GRB.
We acknowledge the excellent support given by the GTC staff.
GCN Circular 19154
Subject
GRB 160303A: X-shooter spectroscopy
Date
2016-03-06T02:22:25Z (10 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D. Malesani (DARK/NBI),
T. Kruehler (MPE Garching), D. Xu (NAOC/CAS), S. Schulze (PUC, MAS),
J. Hjorth (DARK/NBI), N.R. Tanvir (U. Leicester) report on behalf of a
larger collaboration:
We observed the afterglow of GRB 160303A (Beardmore et al.,
GCN 19126; Butler et al., GCN 19131) with ESO���s Very Large Telescope
UT2 equipped with X-shooter (Paranal Observatory, Chile). The spectra
cover the range from 3000 to 18000 AA. Observations consisted of 4x1200s
exposures, starting at 06:03 UT of 4 March 2016 (18.8 hr after the GRB
onset).
The spectrum was obtained when the GRB was at r ~ 24.1 (Klose et al.
GCN 19142) and hence the S/N is rather low, implying that no absorption
feature can be identified. In spite of this, a trace can be seen in the
complete UVB (3000-5600AA) and VIS (5600-10100 AA) spectra. The
continuum is rather blue, as already seen from multiband photometry
(Butler et al., GCN 19131; Graham et al., GCN 19144). The detection of the
trace down to 3000 AA implies a redshift limit of < 2.3 (considering that the
Lyman break is not within the range).
In spite of the deep spectrum, we have not been able to identify any emission
feature, which could be indicative of a very faint galaxy and/or a non star
forming galaxy (which would be expected for a SGRB).
We acknowledge excellent support from the Paranal staff.
GCN Circular 19152
Subject
GRB 160303A: Continued optical monitoring from NOT
Date
2016-03-05T20:35:02Z (10 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), T. Kruehler (MPE Garching)
D. Xu (NAOC/CAS), D. Malesani (DARK/NBI), Z. Cano (U. Iceland),
N.R. Tanvir (U. Leicester),M. Messa (Stockholm Univ., Oskar Klein Centre),
E. Gafton (NOT, Stockholm Univ. and Oskar Klein Centre) and I. R. Losada
(Nordita and Stockholm Univ.) report on behalf of a larger collaboration:
We continued the monitoring of GRB 160303A (Beardmore et al.,
GCN 19126) with MOSCA at the 2.5m Nordic Optical Telescope
(La Palma, Spain).
On a 9x300s observation with mean epoch 2:10 UT of 5 March 2016
(37.27 hr after the burst) we detect the afterglow (Butler et al GCN19131)
at a magnitude of r = 25.2 +/- 0.2, as compared to the SDSS field stars.
This is consistent with the magnitude reported by GROND (Bolmer et al.
GCN 19150) at a similar epoch.
Gathering the r-band data from the different GCNs (Butler et al. GCN19131;
de Ugarte Postigo et al. GCN 19136; Jeong et al. GCN 19140; Im et al.
GCN 19141; Klose et al. GCN 19142; de Ugarte Postigo et al. GCN 19143;
Graham et al. GCN 19144; Bolmer et al. GCN 19150) the light curve seems
to have been flat, or even increasing in brightness during the first 4-8 hrs
after the burst. After this, the light curve begins a steep decay with
alpha = 1.23 +/- 0.14 (F_nu ~ t^-alpha). This is not unlike the behaviour of
other short GRBs, f.ex. GRB 130603B (de Ugarte Postigo et al. 2014
A&A 563, 62), which was interpreted as being a magnetar powered event.
GCN Circular 19151
Subject
GRB 160303A: JCMT SCUBA-2 sub-mm observation
Date
2016-03-05T17:59:00Z (10 years ago)
From
Ian Smith at Rice U <ian@spacsun.rice.edu>
I.A. Smith (Rice U.), N.R. Tanvir (U. of Leicester), and Y. Urata (NCU)
report:
We observed the location of the possibly short GRB 160303A (Beardmore
et al., GCN Circ. 19126) using the SCUBA-2 sub-millimeter continuum
camera on the James Clerk Maxwell Telescope. The observation started
at 11:56 UT on 2016-03-03, corresponding to 62 minutes after the burst
trigger. Exposures totaling 2.0 hours were made in good weather
conditions. No source was detected, with the RMS background noise
being 1.4 mJy/beam at 850 microns and 14.8 mJy/beam at 450 microns.
We thank Callie Matulonis and Iain Coulson for the prompt support
of these observations that were taken under project M16AP005.
GCN Circular 19150
Subject
GRB160303A: further GROND observations
Date
2016-03-05T14:33:55Z (10 years ago)
From
Jan Bolmer at MPE/Garching <jan@bolmer.de>
J. Bolmer, J. Greiner (both MPE Garching) and D.A. Kann (TLS Tautenburg) report on
behalf of the GROND team:
We re-observed the field of GRB 160303A (Swift trigger 677495; Beardmore et
al., GCN #19126) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2m MPG telescope at the ESO La Silla
Observatory (Chile).
Observations started at 03:58 UT on 2016-03-05, 41.1h after the GRB
trigger. They were performed at an average seeing of 1.0" and at an
average airmass of 1.6.
We still detect a faint source at the initially reported position (Graham et al. GCN#19144,
de Ugarte Postigo et al. (GCN #19136)).
Based on 96 min of exposure in g'r'i'z', at a mid-time
of 04:52 UT, we derive the following preliminary magnitudes and upper
limits (in AB system):
g' = 25.2 +/- 0.2 mag,
r' = 25.1 +/- 0.2 mag,
i' > 24.3 mag,
z' > 24.4 mag,
Given detections and upper limits are calibrated against SDSS field stars.
No correction for the expected Galactic foreground extinction corresponding
to a reddening of E_(B-V)=0.014 mag in the direction of the burst
(Schlafly & Finkbeiner 2011) has been applied.
Combining our GROND measurements with those from 10.63 h after the GRB
(de Ugarte Postigo et al., GCN #19136), we obtain a decay slope of
alpha = - 1.1 +/- 0.2 in the r' band.
GCN Circular 19149
Subject
GRB 160303A: 9.8 GHz VLA upper limit
Date
2016-03-05T00:51:07Z (10 years ago)
From
Wen-fai Fong at U of Arizona <wfong@email.arizona.edu>
W. Fong (University of Arizona) reports:
"We observed the field of GRB 160303A (Beardmore et al., GCN 19126) with
the Karl G. Jansky Very Large Array (VLA) beginning on 2016 Mar 4.218 UT
(18.32 hr post-burst) at a mean frequency of 9.8 GHz. In 1 hour of
observations, we do not detect any radio source within or around the
enhanced XRT position (Evans et al., GCN 19132) or the optical afterglow
position (Butler et al., GCN 19131; de Ugarte Postigo et al., GCN 19136) to
a 3-sigma limit of 15.2 microJy. We therefore place a 3-sigma limit of 15.2
microJy on the radio afterglow of GRB 160303A at 18.32 hr after the burst.
We thank the VLA staff for quickly executing these observations."
GCN Circular 19148
Subject
GRB 160303A, Swift-BAT refined analysis
Date
2016-03-04T22:56:56Z (10 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
T. N. Ukwatta (LANL), S. D. Barthelmy (GSFC), A. P. Beardmore (U Leicester),
J. R. Cummings (GSFC/UMBC), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC), J. P. Norris (BSU),
D. M. Palmer (LANL), T. Sakamoto (AGU), M. Stamatikos (OSU)
(i.e. the Swift-BAT team):
Using the data set from T-61 to T+200 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 160303A (trigger #677495)
(Beardmore, et al. GCN Circ. 19126). The BAT ground-calculated position is
RA, Dec = 168.710, 22.710 deg which is
RA(J2000) = 11h 14m 50.3s
Dec(J2000) = +22d 42' 35.1"
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 96%.
The mask-weighted light curve shows a short spike that start and peaks at ~T0,
and ends at ~T+0.4 s. There is a hint of a weak tail that lasts till ~T+5 s
T90 (15-350 keV) is 5.0 +- 0.8 sec (estimated error including systematics).
Note that for this burst, the auto process generates fairly inconsistent results of the
burst durations (ranging from T90 of ~ 0.4 s to T90 of ~ 18 s) when using light curves
with different time bins and/or different length of data range. This is likely due to the
ambiguous weak-tail feature in the light curve after the short spike.
Thus, we did further checks of the reality of the weak tail by an alternative Bayesian
Block method based on Scargle et al. (2013), and by searching for detections in
images created using different time intervals. We conclude that there is likely no burst
emission after ~T+5 s, because no burst structure is picked out by the alternative
Bayesian Block method afterwards, and also the signal-to-noise ratio is only about
one in images created after ~T+5. The image created using T+1 s to T+5 s gives
a signal-to-noise ratio of ~ 4.
The lag analysis using the 8-ms binned light curve shows a lag of 24 ms +- 24 ms
for the 100-350 keV to 25-50 keV band, which is inconclusive for the burst nature
due to the weakness of the burst.
We therefore decided to report T90 based on results using data till ~T0+200 s,
which gives a T90 of ~ 5 s and is consistent with our checks. However, due to
the relatively low significance of the tail. We report the spectral analyses for
both the total range and the the short spike.
The time-averaged spectrum from T-0.1 to T+5.3 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.01 +- 0.33. The fluence in the 15-150 keV band is 1.5 +- 0.3 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.09 sec in the 15-150 keV band
is 1.0 +- 0.1 ph/cm2/sec.
The spectrum of the short spike from T-0.09 to T+0.40 sec is best fit by a simple
power-law model. The power law index of the short-spike spectrum is
0.84 +- 0.20. The fluence in the 15-150 keV band is 8.78 +- 1.1 x 10^-8 erg/cm2.
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/677495/BA/
GCN Circular 19147
Subject
GRB 160303A: MMT Optical Detection
Date
2016-03-04T19:45:16Z (10 years ago)
From
Wen-fai Fong at U of Arizona <wfong@email.arizona.edu>
W. Fong (University of Arizona) reports on behalf of a larger collaboration:
"We observed the location of the possibly short-duration GRB 160303A
(Beardmore et al., GCN 19126) with MMTCam mounted on the 6.5-m MMT at a
mid-time of 2016 Mar 4.232 UT (18.64 hr post-burst). We obtained 9x200-sec
of r-band observations in 1.0" seeing at a mean airmass of 1.2. We detect
the optical afterglow (Butler et al., GCN 19131) with a magnitude of
r(AB)~23.90 +/- 0.15 (calibrated to SDSS) at a position consistent with the
NOT position (de Ugarte Postigo et al., GCN 19136). Our measured afterglow
brightness is consistent with the VLT value at a similar epoch (Klose et
al., GCN 19142)."
GCN Circular 19146
Subject
GRB 160303A: Continued RATIR Optical and NIR Observations
Date
2016-03-04T18:38:31Z (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 GRB 160303A (Beardmore, et al., GCN 19126) 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 4.12 to 2016/03 4.53
UTC (16.00 to 25.72 hours after the BAT trigger), obtaining a total of
5.52 hours exposure in the r and i bands and 2.27 hours exposure in the
Z, Y, J, and H bands.
The source reported by Butler et al. (GCN 19131) is not detected in our
images. In comparison with the SDSS DR9 and 2MASS catalogs, we obtain
the following upper limits (3-sigma):
r > 23.77
i > 23.88
Z > 22.37
Y > 21.77
J > 21.52
H > 21.45
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. Our upper limits are consistent
with the GROND measurements (Graham et al., GCN 19144) and confirm that
the source was the afterglow of GRB160303A.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 19144
Subject
GRB 160303A: GROND Optical Detection
Date
2016-03-04T16:33:25Z (10 years ago)
From
Philip Wiseman at MPE/Swift <wiseman@mpe.mpg.de>
J. Graham, J. Bolmer, P. Wiseman and J. Greiner (all MPE Garching) report on
behalf of the GROND team:
We observed the field of GRB 160303A (Swift trigger 677495; Beardmore et
al., GCN #19126) simultaneously in g'r'i'z'JHK with GROND (Greiner et al.
2008, PASP 120, 405) mounted at the 2.2m MPG telescope at the ESO La Silla
Observatory (Chile)./
/Observations started at 03:27 UT on 2016-03-04, 16.5h after the GRB
trigger. They were performed at an average seeing of 1.3" and at an
average airmass of 1.6./
/We detect a single source at the edge of the Swift-XRT error circle
reported by Evans et al. (GCN #19132) consistent with the optical
candidate from de Ugarte Postigo et al. (GCN #19136) and Klose et al.
(GCN #19142)/
/Based on 66 min of exposure in g'r'i'z' and 60 min in JHK, at a mid-time
of 04:54 UT, we derive the following preliminary magnitudes and upper
limits (in AB system):/
/g' = 24.2 +/- 0.1 mag,
r' = 24.0 +/- 0.1 mag,
i' = 23.9 +/- 0.2 mag,
z' = 23.5 +/- 0.3 mag,
J > 21.1 mag,
H > 20.1 mag, and
K > 19.5 mag./
/Given detections and upper limits are calibrated against SDSS
as well as 2MASS field stars. No correction for the expected Galactic
foreground extinction corresponding to a reddening of E_(B-V)=0.014 mag in
the direction of the burst (Schlafly & Finkbeiner 2011) has been applied.
--
Philip Wiseman wiseman@mpe.mpg.de
Doctoral Student +49 (0)89 30000-3566
GRB Group +49 (0)1605 011752
IMPRS Student Representative
Room X5 1.3.09
Max-Planck-Institute fuer extraterrestriche Physik
Giessenbachstrasse 1
85748 Garching, Germany
GCN Circular 19143
Subject
GRB 160303A: Observations from T150 OSN
Date
2016-03-04T15:46:17Z (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) report on behalf of a larger collaboration:
We observed the field of the possibly short GRB 160303A (Beardmore et al.,
GCN 19126) with the 1.5 m OSN telescope (Sierra Nevada Observatory,
Granada, Spain). Observation consisted of 15x300s exposures in R-band,
ranging from 01:37-3:00 UT (mean epoch at 15.41 hr after the burst).
In the combined image the GRB afterglow (Butler et al., GCN 19131; Emery
et al. GCN 19134; de Ugarte Postigo, GCN 19136; Jeong et al. GCN19140;
Im et al. GCN 19141; Klose et al. GCN 19142) is seen at a magnitude of
r(AB) = 23.67 +/- 0.27 as compared to SDSS stars.
This seems to indicate confirm the decay as compared with the data of
RATIR (Butler et al., GCN 19131), NOT (de Ugarte Postigo, GCN 19136) and
CQUEAN (Jeong et al. GCN19140), BOAO (Im et al. GCN 19141) and FORS
(Klose et al. GCN 19142). In any case the possible decay would be shallower
than the typical GRB, with a decay slope of alpha ~ 0.5 (F_nu ~ t^-alpha).
GCN Circular 19142
Subject
GRB 160303A: VLT/FORS2 afterglow obervations
Date
2016-03-04T15:36:10Z (10 years ago)
From
Thomas Kruehler at MPE Garching <kruehler@mpe.mpg.de>
S. Klose, A. Nicuesa Guelbenzu (both TLS Tautenburg),
T. Kruehler (MPE Garching), D. Malesani (DARK/NBI) and J. Greiner
(MPE Garching) report on behalf of a larger collaboration:
We observed the field of GRB 160303A (Swift trigger 677495; Beardmore et
al., GCN #19126) with FORS2 at ESO's Very Large Telescope. Imaging in
the R-band filter started at 05:40:42 UT on 2016-03-04, 18.8 hr after
the GRB trigger.
In a 4x25 s exposure, we clearly detect the candidate counterpart
(Butler et al. GCN#19131, Emery & Beardmore, GCN#19134,
de Ugarte Postigo et al. GCN#19136) at a position consistent with
the one provided by de Ugarte Postigo et al. (GCN#19136). The source
appears point-like in the image which has a stellar PSF with a
FWHM of 0.72".
Calibrating our data against r-band photometry of field stars
from the SDSS catalog, we measure a preliminary AB magnitude of
r = 24.11 +- 0.15
This implies significant fading against the earlier measurements from
Butler et al. (GCN#19131) and de Ugarte Postigo et al. (GCN#19136),
indicating that this source is the GRB afterglow (see also Im et al.,
GCN#19141).
We acknowledge excellent support from ESO Paranal Science Operations,
in particular from Emanuela Pompei and the team at VLT/Antu.
[GCN OPS NOTE(06mar16): Per author's request, the final paragraph was added.]
GCN Circular 19141
Subject
GRB 160303A: BOAO R-band Detection
Date
2016-03-04T15:28:40Z (10 years ago)
From
Myungshin Im at Seoul Nat U <mim@astro.snu.ac.kr>
Myungshin Im (CEOU/SNU), Hyun-Il Sung (KASI), Yuji Urata (NCU),
Soomin Jeong (SKKU/IAA-CSIC)
We observed the field of GRB 160303A (Beardmore et al. GCN 19126)
using the 1.8m telescope at the Bohyunsan Optical Astronomy Observatory
��� ���
(BOAO) in Korea. The observation started at
2016-02-28 13:31:46 UT,
��� ���
or about 2.6 hours after the BAT alert.
We clearly identify the afterglow at the location of the RATIR detection
(Butler et al. GCN 19131) with R = 22.75 +- 0.12 mag in a stacked
image of 6 x 5 min frames (Mid-point: 2016-02-28 13:54). Together with the
��� result���
at 10
��� ���
hrs after the BAT alert (de Ugarte Postiago et al.
������
GCN 19136), our photometry unambiguously confirms the fading nature of this
source. Further observation and the analysis of the data are
planned.
We thank the BOAO staffs for their assistance with the observation.
GCN Circular 19140
Subject
GRB 160303A: McDonald 2.1m CQUEAN Detection
Date
2016-03-04T12:34:56Z (10 years ago)
From
Soomin Jeong at IAA-CSIC <sjeong@iaa.es>
Soomin Jeong (SKKU/IAA-CSIC), Myungshin Im, Changsu Choi and Gu Lim (CEOU/SNU) on behalf of a larger collaboration:
We observed the field of GRB160303A (Beardmore et al., GCN 19126) with CQUEAN at the Otto Struve 2.1 m telescope
in McDonald Observatory, Texas. The observation started at 11:44, Mar 03 UT (i.e. 0.83 hr post burst) and the observation
was conducted in r-, i-, R-, z- band.
In the median combined image (5 x 120s) of i-band, a possible counterpart is detected near the centre of XRT enhanced
position (Evans et al., GCN 19132). We noticed that our i-band detection is slightly offset from a previously identified position
by RATIR (Butler et al., GCN 19131) and found another marginal detection at the RATIR detection, i.e., outskirt of XRT
enhanced position (Evans et al., GCN 19132).
Faint features are barely detected also in an 5 x 120s, r-band exposure, however the detection error is too big to reveal its reality.
It is in relatively outskirt within XRT enhanced error circle and at the previously reported optical position (Butler et al., GCN 19131; Emery et al., GCN 19134).
In comparison to other reports, the detection in i-band looks like a fading afterglow (Butler et al., GCN 19131), and the position of
the possible object in r-band is coincident to the previous optical detection by RATIR (Butler et al., GCN 19131) and NOT (De Ugarte et al., GCN 19136).
The faint r-band source could be the host galaxy or highly contaminated counterpart from the underlying host.
The analysis of R- and z-band images is still ongoing.
T_mid (hr) Exposure (s) Filter Magnitude (AB)
-----------------------------------------------------------------------------------
0.92 5x120 i 22.54 +/- 0.26
1.13 5x120 r 23.06 +/- 0.41
------------------------------------------------------------------------------------
The fields are calibrated to a nearby star at RA=168.701176, Dec=22.745212 from SDSS.
GCN Circular 19139
Subject
GRB 160303A SMA observation
Date
2016-03-04T06:54:27Z (10 years ago)
From
Yuji Urata at Nat. Central U. <urata@astro.ncu.edu.tw>
GRB 160303A SMA observation
Y. Urata (NCU), K.Y Huang (NTNU), and G. Petitpas (SMA)
We observed the optical afterglow position of GRB 130303A (Butler et
al., GCN Circ. 19131) using the Sub-Millimeter Array (SMA). The
observation in 230 GHz band was started at March 3 12:47 (UT) about
1.9 hrs after the burst. Our preliminary analysis shows no
counterpart brighter than 2.4 mJy (3-sigma).
GCN Circular 19138
Subject
GRB 160303A iTelescope observation
Date
2016-03-04T02:26:10Z (10 years ago)
From
Takanori Sakamoto at AGU <tsakamoto@phys.aoyama.ac.jp>
T. Sakamoto, Y. Kitaoka, A. Yoshida (AGU)
We observed the field of GRB 160303A detected by Swift (trigger #677495;
Beardmore et al., GCN Circ. 19126) with the iTelescope.Net (http://www.itelescope.net)
T21 (Plane Wave 17" CDK) telescope located at the New Mexico Skies Observatory
(NM, USA).
15 images of 60 sec exposures were taken in the R filter starting from March 3 11:19:26 (UT)
about 25 minutes after the trigger and stopped on March 3 11:38:20 (UT).
We do not detect the optical afterglow both in the individual images and the stacked image
at the X-ray and the optical afterglow position (Evans et al., GCN Circ. 19132;
Butler et al., GCN Circ. 19131). The estimated five sigma upper limit of the combined
image (total exposure of 900 sec) is ~18.3 using the USNO-B1 catalog.
GCN Circular 19137
Subject
GRB 160303A: Swift-XRT refined Analysis
Date
2016-03-03T23:40:56Z (10 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
D.N. Burrows (PSU), P.A. Evans (U. Leicester), S.L. Gibson (U.
Leicester), J.P. Osborne (U. Leicester), A. Melandri (INAF-OAB), P.
D'Avanzo (INAF-OAB), V. D'Elia (ASDC), T.G.R. Roegiers (PSU), L.M.
McCauley (PSU) and A.P. Beardmore report on behalf of the Swift-XRT
team:
We have analysed 7.0 ks of XRT data for GRB 160303A (Beardmore et al.
GCN Circ. 19126), from 87 s to 23.3 ks after the BAT trigger. The data
comprise 9 s in Windowed Timing (WT) mode (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.
19132).
The light curve can be modelled with a power-law decay with a decay
index of alpha=2.36 (+0.17, -0.16).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.70 (+0.24, -0.22). The
best-fitting absorption column is 5.2 (+6.7, -4.1) x 10^20 cm^-2,
consistent with the Galactic value of 1.1 x 10^20 cm^-2 (Willingale et
al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum is 3.8 x 10^-11 (4.1 x
10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 5.2 (+6.7, -4.1) x 10^20 cm^-2
Galactic foreground: 1.1 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index: 1.70 (+0.24, -0.22)
If the light curve continues to decay with a power-law decay index of
2.36, the count rate at T+24 hours will be 6.7 x 10^-7 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 2.6 x
10^-17 (2.8 x 10^-17) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00677495.
This circular is an official product of the Swift-XRT team.
GCN Circular 19136
Subject
GRB 160303A: Optical observations from the NOT
Date
2016-03-03T23:39:37Z (10 years ago)
From
Antonio de Ugarte Postigo at IAA-CSIC <deugarte@iaa.es>
A. de Ugarte Postigo (IAA-CSIC, DARK/NBI), D. Malesani (DARK/NBI),
N.R. Tanvir (U. Leicester), Z. Cano (U. Iceland), M. Messa (Stockholm
Univ., Oskar Klein Centre), E. Gafton (NOT, Stockholm Univ. and Oskar
Klein Centre) and I. R. Losada (Nordita and Stockholm Univ.) report on
behalf of a larger collaboration:
We observed the field of the possibly short GRB 160303A (Beardmore et al.,
GCN 19126) with MOSCA at the 2.5m Nordic Optical Telescope (La Palma,
Spain). Observations started at 21:32 UT (10.63 hr after the burst). In an
8x300s r-band exposure we detect a source consistent with the counterpart
candidate identified by RATIR (Butler et al. GCN 19131), and also seen by
UVOT (Emery et al. GCN 19134).
Comparing with SDSS field stars we obtain a photometric value of
r=23.43+/-0.15 (AB). This would imply only a modest (if any) fading
compared to the RATIR observation. This may be indicative of a significant
contribution from an underlying host galaxy.
We do note that the coordinates that we measure are slightly offset from
those given in the RATIR GCN, being our object marginally outside the
refined XRT error circle(Evans et al., GCN 19132,
http://www.swift.ac.uk/xrt_positions/00677495/ <http://www.swift.ac.uk/xrt_positions/00677495/>), at the following coordinates
(J2000, +/- 0.3"):
RA = 11:14:48.06
Dec = +22:44:32.2
GCN Circular 19134
Subject
GRB 160303A: Swift/UVOT Detection
Date
2016-03-03T20:15:46Z (10 years ago)
From
Sam Emery at MSSL-UCL <samuel.emery.15@ucl.ac.uk>
S.W.K. Emery (UCL-MSSL) and A. P. Beardmore (U Leicester)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 160303A
109 s after the BAT trigger (Beardmore et al., GCN Circ. 19126).
We detect a fading source consistent with the XRT position
(Beardmore et al. GCN Circ. 19126) and the RATIR optical and NIR afterglow
detections (Butler et al. GCN Circ 19131)
in the initial UVOT u filter 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) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 109 259 147 >21.9
u_FC 321 571 246 20.75
white 109 2061 450 >22.5
b 576 2037 136 >19.9
w1 700 2161 77 >20.5
m2 1426 1445 19 >19.5
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 19133
Subject
GRB 160303A: RAPTOR Observations During Gamma-Ray Emitting Interval
Date
2016-03-03T19:05:45Z (10 years ago)
From
James Wren at LANL <jwren@lanl.gov>
J. Wren, W.T. Vestrand, P. Wozniak, and H. Davis
of Los Alamos National Laboratory report:
The RAPTOR network of robotic optical telescopes made observations of Swift
trigger 677495 (Beardmore, et al., GCN 19126). The burst location was within
the field of our wide-field monitor located in Maui, HI, which began a 10 s
integration of the location beginning at 10:54:38.19 UT, 3.86 s before the
Swift trigger time and during the gamma-ray emitting interval. We do not
detect an optical counterpart to a limiting magnitude of 10.5. Our 3-sigma
limiting magnitudes are based on a comparison of our unfiltered image to the
Tycho-2 V-band catalog.
GCN Circular 19132
Subject
GRB 160303A: Enhanced Swift-XRT position
Date
2016-03-03T14:09:07Z (10 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 2035 s of XRT Photon Counting mode data and 2 UVOT
images for GRB 160303A, 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 = 168.70075, +22.74213 which is equivalent
to:
RA (J2000): 11h 14m 48.18s
Dec (J2000): +22d 44' 31.7"
with an uncertainty of 1.8 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 19131
Subject
GRB 160303A: RATIR Optical and NIR Afterglow Detection
Date
2016-03-03T13:07:10Z (10 years ago)
From
Nat Butler at UC berkeley <natxbutler@gmail.com>
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 160303A (Beardmore, et al., GCN 19126) 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 3.46 to 2016/03 3.52 UTC (1.8
minutes to 1.50 hours after the BAT trigger), obtaining a total of 1.02
hours exposure in the r and i bands and 0.44 hours exposure in the Z, Y, J,
and H bands.
We detect an uncatalogued source within the Swift-XRT error circle, in
comparison with the SDSS DR9 and 2MASS catalogs, we obtain the following
detections and upper limits (3-sigma):
r = 22.95 +/- 0.31
i = 22.65 +/- 0.23
Z > 21.98
Y = 21.83 +/- 0.36
J > 21.30
H > 21.01
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. The source is located at RA, Dec =
11:14:48.12, +22:44:32.6 (J2000, +/-0.5").
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 19130
Subject
GRB 160303A: MITSuME Akeno optical upper limits
Date
2016-03-03T12:24:54Z (10 years ago)
From
Taketoshi Yoshii at Tokyo Tech <yoshii.t.ac@m.titech.ac.jp>
Y.Tachibana, T.Fujiwara, T. Yoshii, Y. Saito, H. Ohuchi, Y. Yano, S. Kurita, S.Harita, Y.Muraki, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:
We searched for the optical counterpart of GRB 160303A (Beardmore et al., GCN Circular #19126) with the
optical three color (g', Rc, and Ic) CCD cameras attached to the MITSuME 50 cm
telescope of Akeno Observatory, Yamanashi, Japan.
The observation started on 2016-03-03 10:55:44 UT (~1 min after the burst).
We did not find any new point source within XRT circle in all three bands.
We obtained following limits for the magnitudes.
T0+[hour] MID-UT T-EXP[sec] g' Rc Ic
----------------------------------------------------------------------------
0.43 11:20:38 2610 >20.3 >20.4 >19.6
----------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used GSC2.3 catalog for flux calibration.
GCN Circular 19129
Subject
GRB 160303A: LCOGT-FTN optical observations
Date
2016-03-03T12:20:57Z (10 years ago)
From
Simone Dichiara at Ferrara U/Italy <dichiara@fe.infn.it>
S. Dichiara (U. Ferrara, ICRANet), C. Guidorzi (U. Ferrara), S. Kobayashi
(LJMU), A. Gomboc (U. Nova Gorica), C.G. Mundell (U. Bath), on behalf of a
larger collaboration report:
The 2-m LCOGT Faulkes Telescope North began observing Swift GRB 160303A
(Beardmore et al., GCN 19126) on March 03, 11:18 UT (23 minutes after the
burst trigger) with i' filter. Inside the XRT error circle we find no
source down to i'> 21.2 mag in a 5x120s exposure (at 28.7 min, mid time),
as calibrated against nearby SDSS stars, in agreement with the limits
reported by Elenin et al. (GCN 19127).
GCN Circular 19128
Subject
GRB 160303A: MITSuME Okayama upper limits
Date
2016-03-03T12:14:30Z (10 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 MITSuME and OISTER collaboration:
We observed the field of GRB 160303A (Beardmore et al., GCNC 19126)
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 2016-03-03 10:57:10 UT (~2.5 min after
the burst). We did not find any new point source within the XRT
circle (Beardmore et al., GCNC 19126) in all the three bands.
Three sigma upper limits of the OT are listed below.
We used SDSS-DR8 catalog for flux calibration.
#T0+[day] MID-UT T-EXP[sec] g' Rc Ic
-----------------------------------------------------
0.00532 11:02:21 540.0 >18.5 >18.6 >18.0
0.01940 11:22:38 2520.0 >19.5 >19.6 >19.0
-----------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
GCN Circular 19127
Subject
GRB 160303A: ISON-NM early optical early limits
Date
2016-03-03T12:10:37Z (10 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
L. Elenin (KIAM), E. Mazaeva (IKI), A. Volnova (IKI), I. Molotov
(KIAM), A. Pozanenko (IKI) report on behalf of larger GRB follow-up
collaboration:
We observed the field of the Swift GRB 160303A (Beardmore et al., GCN
19126) with 0.4-m telescope of ISON-NM observatory starting on Mar., 03
(UT) 10:56:02, i.e. ~80 seconds after burst trigger. We obtained 30
unfiltered images of 30 s exposure. We do not detect any source within
XRT error circle (Beardmore et al., GCN 19126) both in the first image
and in a combined image:
UT start t-T0 Exp. Filter UL (3sigma)
(mid.,days) (s)
10:56:02 0.00110 1*30 Clear 19.8
10:56:02 0.00971 30*30 Clear 21.7
The photometry is based on nearby USNO-B1.0 stars
GCN Circular 19126
Subject
GRB 160303A: Swift detection of a burst, possibly short
Date
2016-03-03T11:14:26Z (10 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
A. P. Beardmore (U Leicester), D. N. Burrows (PSU),
P.A. Evans (U Leicester), L. M. McCauley (PSU),
K. L. Page (U Leicester) and D. M. Palmer (LANL) report on behalf of
the Swift Team:
At 10:54:42 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 160303A (trigger=677495). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 168.681, +22.742 which is
RA(J2000) = 11h 14m 44s
Dec(J2000) = +22d 44' 33"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows a single peak
structure with a duration of about 0.5 s sec. There is some suggestion
of additional peaks at T-1 and T+5. The peak count rate
was ~6000 counts/sec (15-350 keV), at ~0.1 sec after the trigger.
The XRT began observing the field at 10:56:26.1 UT, 104.1 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 168.7005,
22.7424 which is equivalent to:
RA(J2000) = 11h 14m 48.11s
Dec(J2000) = +22d 44' 32.5"
with an uncertainty of 2.2 arcseconds (radius, 90% containment). This
location is 64 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 1.07
x 10^20 cm^-2 (Willingale et al. 2013).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 108 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 A. P. Beardmore (apb AT star.le.ac.uk).
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.)