GRB 130131A
GCN Circular 14156
Subject
GRB 130131A: Swift detection of a burst
Date
2013-01-31T14:06:54Z (12 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
D. Grupe (PSU), B. N. Barlow (PSU), S. D. Barthelmy (GSFC),
A. P. Beardmore (U Leicester), S. T. Holland (STScI),
J. A. Kennea (PSU), C. B. Markwardt (NASA/GSFC),
F. E. Marshall (NASA/GSFC), C. Pagani (U Leicester),
B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU),
M. Stamatikos (OSU/NASA/GSFC), R. L. C. Starling (U Leicester) and
T. N. Ukwatta (MSU) report on behalf of the Swift Team:
At 13:56:22 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 130131A (trigger=547407). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 171.108, +48.069 which is
RA(J2000) = 11h 24m 26s
Dec(J2000) = +48d 04' 10"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve shows two peak: 1 5-sec peak
at T+0 sec and a 100-sec peak at T+50 sec.
with a total duration of about 60 sec. The peak count rate
was ~1400 counts/sec (15-350 keV), at ~1 sec after the trigger.
The XRT began observing the field at 13:57:20.5 UT, 58.5 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
uncatalogued X-ray source located at RA, Dec 171.12193, 48.07520 which
is equivalent to:
RA(J2000) = 11h 24m 29.26s
Dec(J2000) = +48d 04' 30.7"
with an uncertainty of 4.4 arcseconds (radius, 90% containment). This
location is 40 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. We
cannot determine whether the source is fading at the present time.
A power-law fit to a spectrum formed from promptly downlinked event
data gives a column density consistent with the Galactic value of 1.45
x 10^20 cm^-2 (Kalberla et al. 2005).
The initial flux in the 2.5 s image was 1.22e-08 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 67 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
0.01.
Burst Advocate for this burst is D. Grupe (dxg35 AT psu.edu).
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 14157
Subject
GRB 130131A - UKIRT afterglow candidate
Date
2013-01-31T16:23:37Z (12 years ago)
From
Nial Tanvir at U.Leicester <nrt3@star.le.ac.uk>
N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick), T. Wold (JACH)
report on behalf of a larger collaboration:
We observed the field of GRB 130131A (Grupe et al. GCN 14166)
with the WFCAM camera on UKIRT, beginning approximately 54 mins
after the BAT trigger.
Within the XRT error circle we detect a single, bright point source
at position:
11 24 30.39
+48 04 33.3
(J2000, uncertainty ~0.5")
Provisional Vega magnitudes (relative to a nearby 2MASS source) are K=16.4,
J=19.4, indicating a rather red source.
Further observations and analysis are ongoing.
GCN Circular 14158
Subject
GRB 130131A - Faulkes Telescope North Observations
Date
2013-01-31T16:27:53Z (12 years ago)
From
Francisco Virgili at Liverpool John Moores U <fjv@astro.livjm.ac.uk>
F.J. Virgili (LJMU), C. Guidorzi (U. Ferrara), and A. Melandri
(INAF-OAB) report:
"The 2-m Faulkes Telescope North robotically followed up GRB 130131A
(Swift trigger 547407, Grupe et al. GCN 14156) 2.88 min after the GRB
trigger time. No optical counterpart is detected
within the XRT error circle to the following conservative limits:
Midtime from GRB Exposure Filter Magnitude
(min) (s)
-------------------------------------------------
3.4 3x10s R >19.2
28.9 720s R >20.6
33.7 700s i' >20.1
-------------------------------------------------
Magnitudes are calibrated with nearby USNOB-1 and SDSS stars."
GCN Circular 14160
Subject
GRB 130131A: Enhanced Swift-XRT position
Date
2013-01-31T21:29:21Z (12 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 574 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 130131A, 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 = 171.12621, +48.07589 which is equivalent
to:
RA (J2000): 11h 24m 30.29s
Dec (J2000): +48d 04' 33.2"
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 14163
Subject
GRB 130131A: Swift-BAT refined analysis
Date
2013-01-31T23:03:50Z (12 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
D. M. Palmer (LANL), S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC),
J. R. Cummings (GSFC/UMBC), E. E. Fenimore (LANL), N. Gehrels (GSFC),
D. Grupe (PSU), H. A. Krimm (GSFC/USRA), A. Lien (GSFC/ORAU),
C. B. Markwardt (GSFC), T. Sakamoto (AGU), G. Sato (ISAS),
M. Stamatikos (OSU), J. Tueller (GSFC), T. N. Ukwatta (MSU)
(i.e. the Swift-BAT team):
Using the data set from T-239 to T+903 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 130131A (trigger #547407)
(Grupe, et al., GCN Circ. 14156). The BAT ground-calculated position is
RA, Dec = 171.091, 48.064 deg which is
RA(J2000) = 11h 24m 21.9s
Dec(J2000) = +48d 03' 51.0"
with an uncertainty of 2.1 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 97%.
The mask-weighted light curve shows two separated peaks: (1) starting at ~T-5 sec,
peaking at ~T+1 sec, and ending at ~T+15 sec, and (2) T+35, T+47, and ~T+65 sec.
T90 (15-350 keV) is 51.6 +- 2.4 sec (estimated error including systematics).
The time-averaged spectrum from T-0.95 to T+52.15 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
2.12 +- 0.32. The fluence in the 15-150 keV band is 3.1 +- 0.6 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.04 sec in the 15-150 keV band
is 0.7 +- 0.1 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/547407/BA/
GCN Circular 14166
Subject
GRB 130131A: MITSuME Okayama optical upper limits
Date
2013-02-01T00:50:07Z (12 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 the MITSuME collaboration:
We observed the field of GRB 130131A (Grupe et al., GCNC 14156)
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 2013-01-31 14:53:53 UT (~58 min after the burst).
We did not find any new point source within the enhanced XRT circle
(Evans et al., GCNC 14160) in all the three bands.
Three sigma upper limits of the OT are listed below. We used
SDSS catalog for flux calibration.
T0+[day] MID-UT T-EXP[sec] g' Rc Ic
------------------------------------------------------
0.10111 16:21:58 9000.0 >20.5 >20.5 >19.9
------------------------------------------------------
T0+ : Elapsed time after the burst [day]
T-EXP: Total Exposure time [sec]
GCN Circular 14168
Subject
GRB 130131A: Swift-XRT refined Analysis
Date
2013-02-01T02:07:03Z (12 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
J.A. Kennea (PSU), M.C. Stroh (PSU), D.N. Burrows (PSU), A.P. Beardmore
(U. Leicester), P.A. Evans (U. Leicester), O.M. Littlejohns (U.
Leicester), A. Maselli (INAF-IASFPA), V. Mangano (INAF-IASFPA), A.
Melandri (INAF-OAB) and D. Grupe report on behalf of the Swift-XRT
team:
We have analysed 9.2 ks of XRT data for GRB 130131A (Grupe et al. GCN
Circ. 14156), from 64 s to 18.8 ks after the BAT trigger. The data
comprise 235 s in Windowed Timing (WT) mode with the remainder in
Photon Counting (PC) mode. The enhanced XRT position for this burst was
given by Evans et al. (GCN. Circ 14160).
The late-time light curve (from T0+5.3 ks) can be modelled with a
power-law decay with a decay index of alpha=1.1 (+0.4, -0.3).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.44 (+/-0.07). The
best-fitting absorption column is 3.17 (+/-0.19) x 10^21 cm^-2, in
excess of the Galactic value of 1.4 x 10^20 cm^-2 (Kalberla et al.
2005). The PC mode spectrum has a photon index of 2.21 (+0.21, -0.20)
and a best-fitting absorption column of 2.4 (+/-0.6) x 10^21 cm^-2. The
counts to observed (unabsorbed) 0.3-10 keV flux conversion factor
deduced from this spectrum is 3.6 x 10^-11 (6.1 x 10^-11) erg cm^-2
count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 2.4 (+/-0.6) x 10^21 cm^-2
Galactic foreground: 1.4 x 10^20 cm^-2
Excess significance: 6.5 sigma
Photon index: 2.21 (+0.21, -0.20)
If the light curve continues to decay with a power-law decay index of
1.1, the count rate at T+24 hours will be 2.6 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 9.3 x
10^-14 (1.6 x 10^-13) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00547407.
This circular is an official product of the Swift-XRT team.
GCN Circular 14171
Subject
GRB 130131A: VLA 5.8 Ghz Detection
Date
2013-02-01T11:22:34Z (12 years ago)
From
Ashley Zauderer at CfA <bevinashley@gmail.com>
T. Laskar, B. A. Zauderer and E. Berger (Harvard) report on behalf of the
CARMA Key Project "A Millimeter View of the Transient Universe":
"We observed the position of GRB 130131A (Grupe et al.;
GCN 14156) beginning 2013 Feb 1.28 (dt=0.7 d) at a
mean frequency of 5.8 Ghz with the Karl G. Jansky Very
Large Array. We detect a source consistent with the
enhanced Swift-XRT position (Evans et al.; GCN 14160)
with a flux of 38 (+/- 11) uJy. The position of this radio
source is
RA (J2000) 11:24:30.4 (+/- 0.2)
DEC (J2000) +48:04:33.0 (+/- 1.5).
Follow-up observations at multiple frequencies are in progress.
We thank the VLA staff for their support."
GCN Circular 14172
Subject
GRB 130131A: CARMA 3mm Observations
Date
2013-02-01T12:56:17Z (12 years ago)
From
Ashley Zauderer at CfA <bevinashley@gmail.com>
B. A. Zauderer, E. Berger, and T. Laskar (Harvard) report on behalf of the
CARMA Key Project "A Millimeter View of the Transient Universe":
"We observed the position of GRB 130131A (Grupe et al., GCN 14156) with
the Combined Array for Research in Millimeter Astronomy beginning
2013 Feb 1.3 UT (0.7 d post-burst) at a mean frequency of ~85 GHz.
Coincident with the Swift-XRT position (Evans et al., GCN 14160) and
the VLA 5.8 GHz position (Laskar et al., GCN 14171), we report
a preliminary detection of a radio source with a flux of ~0.5 mJy.
Further analysis is in progress.
We thank the CARMA staff for their support."
GCN Circular 14175
Subject
GRB 130131A - UKIRT confirmation of afterglow
Date
2013-02-01T14:27:41Z (12 years ago)
From
Nial Tanvir at U.Leicester <nrt3@star.le.ac.uk>
N. R. Tanvir (U. Leicester), A. J. Levan (U. Warwick), T. Wold (JACH)
report on behalf of a larger collaboration:
We re-observed the field of GRB 130131A with the WFCAM camera on
UKIRT, beginning approximately 20.5 hr post-burst. The source reported
by us previously (GCN 14157) is no longer detected in our provisional
reduction, indicating a fading of at least 2 mag in the K-band. This confirms
the source as the afterglow of the GRB (consistent also with the radio detection
by Zauderer et al. GCN 14171).
We also report that the afterglow was faintly visible in a Z-band image
taken at UKIRT 2hr post-burst (in morning twilight), indicating that this
is likely not an extreme redshift event.
GCN Circular 14177
Subject
GRB 130131A: RAPTOR Limits During Gamma-Ray Emitting Interval
Date
2013-02-01T19:23:05Z (12 years ago)
From
James Wren at LANL <jwren@nis.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 547407 (Grupe, et al., GCN 14156). 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 at 13:56:20.65 UT, 1.4 s before the Swift trigger
time and during the gamma-ray emitting interval. During the period that the
BAT was detecting gamma-ray emission, from ~T-5 s to ~T+65 s (Palmer,
et al., GCN 14163), we have a total of four 10 s exposures with limiting
magnitudes of R~9.4 in moderate moonglow. We do not detect the optical
counterpart (Tanvir et al., GCN 14157; Virgili et al., GCN 14158) in any of
our images. Our 3-sigma limiting magnitudes are based on a comparison of
our unfiltered image to the Tycho-2 V-band catalog.
GCN Circular 14178
Subject
GRB 130131A: RATIR optical and infrared upper limits
Date
2013-02-01T23:07:03Z (12 years ago)
From
Ori Fox at UCB <ofox@berkeley.edu>
Ori Fox (UCB), Nat Butler (ASU), Alan M. Watson (UNAM), Alexander
Kutyrev (GSFC), William
H. Lee (UNAM), Michael G. Richer (UNAM), Chris Klein (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UCSC),
Eleonora Troja (GSFC), 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), and Harvey
Moseley (GSFC) report:
Under good weather conditions, we observed the field of GRB 130131A
(Grupe, et al., GCN 14156) 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. An
extremely red (K=16.4, J=19.4) afterglow candidate was detected by
Tanvir, et al. (GCN 14157). We obtained approximately 2.83 hrs (ri) and
1.07 hrs (ZYJH) of data from 2013 February 1.25 to 2023 February 1.42
UTC (16.0 to 20.0 hrs after the BAT trigger)
We detect no source within the XRT error circle (Evans et al; GCN 14160)
or at the position of the UKIRT source (GCN 14157). In comparison with
SDSS DR8 and 2MASS, we derive the following upper limits (3-sigma) in
the AB magnitude system:
r' > 23.8
i' > 23.3
Z > 22.2
Y > 21.8
J > 21.9
H > 21.5
The limits are consistent with the suggested fading of at least 2 mag in
K-band (GCN 14175) measured at 20.5 hours.
These magnitudes 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.
--
Please make note of the new email address.
http://astro.berkeley.edu/~ofox/website/Homepage.html
GCN Circular 14180
Subject
GRB 130131A: Swift/UVOT Upper Limits
Date
2013-02-02T15:19:38Z (12 years ago)
From
Mike Siegel at PSU/Swift MOC <siegel@swift.psu.edu>
M. H. Siegel and D. Grupe (PSU)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 130131A
68 s after the BAT trigger (Grupe et al., GCN Circ. 14156).
No optical afterglow consistent with the optical position (Tanver et al.,
GCN Circ 14157) or XRT position (Evans et al., GCN Circ. 14160)
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) exposure and subsequent exposures are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 68 217 147 >21.8
u_FC 280 529 246 >20.8
white 68 7570 839 >22.5
v 609 18681 1378 >21.0
b 535 7369 549 >21.7
u 280 13670 1434 >22.0
w1 658 12906 1434 >21.7
m2 1932 18851 1263 >21.3
w2 758 17768 1336 >22.0
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.01 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 14182
Subject
GRB 130131A: optical observation in Mondy observatory
Date
2013-02-06T20:27:48Z (12 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Volnova (SAI MSU/IKI), I. Korobtsev (ISTP), E. Klunko (ISTP), A.
Pozanenko (IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of the Swift GRB 130131A (Grupe et al., GCN 14156)
with AZT-33IK telescope of Sayan observatory (Mondy). We took several
images in R-filter of 60 s exposure on Jan. 31, between (UT)
14:12:36-15:36:53 under favorable weather conditions with a FWHM of
about 2.5". In the stacked images we detected a source which is
coincident with the source reported by Tanvir et al. (GCN 14157). The
photometry based on SDSS DR8 is the following:
t_start, T0+ (mid), filter, exp., OT+/-err UL (3 sigma)
(UT) d s
14:12:36 0.01640 R 10x60 22.5 +/-0.35 22.4
14:12:36 0.04053 R 79x60 23.4 +/-0.25 23.5
Taken coincidence with source detected in IR (Tanvir et al. GCN 14157)
and fading nature of the source we suggest that we detect OT of GRB
130131A. The detection in R filter confirms that the GRB 130131A is not
an extreme redshift event (Tanvir et al. GCN 14175). Also we compared
fluxes in X-ray and optic at ~0.016 days after trigger and found that
the GRB 130131A can be considered as optically dark burst following the
both criteria (Jakobsson et al., 2004; van der Horst et al., 2009).
The stars used for photometry and assumed R mags:
J112419.01+480710.6 11:24:19.01 +48:07:10.7 R = 18.93
J112414.86+480528.8 11:24:14.86 +48:05:28.9 R = 18.77
J112419.60+480357.4 11:24:19.61 +48:03:57.5 R = 20.32
The finding chart of the stacked image can be found in
http://grb.rssi.ru/GRB130131A/GRB130131A_130131_AZT33IK.png
GCN Circular 14194
Subject
GRB 130131A: MITSuME Akeno Optical upper limits
Date
2013-02-10T14:00:06Z (12 years ago)
From
Yoichi Yatsu at Tokyo Tech. <yatsu@hp.phys.titech.ac.jp>
M. Hayashi, T. Yoshii, R. Usui, Y.Aoki, S. Kurita,
Y. Saito, Y. Yatsu, and N. Kawai (Tokyo Tech)
report on behalf of the MITSuME collaboration:
We observed GRB 130131A (Grupe et al., GCNC 14156) 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 2013-01-31 13:57:11 UT ( ~49 sec after
the burst). And we could not find any new point source within the XRT
error circle in all the three bands.
The results of photometry (3 sigma upper limits) are listed below.
The photon flux were calibrated against GSC2.3 catalog.
T0+[sec] MID-UT T-EXP[sec] g' Rc Ic
-------------------------------------------------------------------------------------------
33 13:57:44 60 >17.6 >17.8 >17.1
159 13:59:51 270 >18.5 >18.6 >18.0
1105 14:15:46 1440 >19.0 >19.4 >18.9
7119 15:56:00 9540 >19.9 >20.6 >19.8
-------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst [sec]
T-EXP: Total Exposure time [sec]
GCN Circular 14281
Subject
GRB 130131A: JCMT SCUBA-2 sub-mm observations
Date
2013-03-11T01:49:17Z (12 years ago)
From
Ian Smith at Rice U <ian@spacsun.rice.edu>
I.A. Smith (Rice U.), R.P.J. Tilanus (Leiden Observatory), N.R. Tanvir
(U. of Leicester), D.A. Frail (NRAO) report:
We observed the location of GRB 130131A (Grupe et al., GCN Circ. 14156)
twice using the SCUBA-2 sub-millimeter continuum camera on the James
Clerk Maxwell Telescope. The first observation started at 14:36 UT on
2013-01-31, corresponding to 40 minutes after the burst trigger. It
lasted 2.0 hours in good weather conditions. The second observation
started at 12:40 UT on 2013-02-01, corresponding to 0.95 days after
the burst trigger. It lasted 2.1 hours in good weather conditions.
No source was significantly detected in the individual or combined
observations at the VLA location (Laskar et al., GCN Circ. 14171).
The combined RMS was 2.2 mJy/beam at 850 microns and 18.2 mJy/beam at
450 microns.
We thank Iain Coulson, Jim Hoge, Callie McNew, Alexander Karim, and
William Montgomerie for their prompt support of these observations.