GRB 130515A
GCN Circular 14688
Subject
GRB 130515A: Suzaku WAM observation of the prompt emission
Date
2013-05-21T14:13:58Z (12 years ago)
From
Masanori Ohno at Hiroshima U <ohno@hep01.hepl.hiroshima-u.ac.jp>
W. Iwakiri(RIKEN), M. Tashiro, Y. Terada, T. Yasuda, Y. Ishida, H. Ueno,
S. Sugimoto (Saitama U.),
M. Ohno, K. Takaki, T. Kawano, R. Nakamura, S. Furui, Y. Fukazawa
(Hiroshima U.),
M. Yamauchi, N. Ohmori, M. Akiyama (Univ. of Miyazaki),
K. Yamaoka (Nagoya U.), S. Sugita (Ehime U.), Y. E. Nakagawa, M. Kokubun,
T. Takahashi (ISAS/JAXA), Y. Hanabata (ICRR),
Y. Urata (NCU), K. Nakazawa, K. Makishima (Univ. of Tokyo)
on behalf of the Suzaku WAM team, report:
The short GRB 130515A (Swift/BAT trigger #555880 ; Malesani et al., GCN
14650; Barthelmy et al., GCN 14658; Fermi-GBM detection: Jenke, GCN
14663; Konus-Wind detection : Golenetskii et al., GCN 14668) triggered
the Suzaku Wide-band All-sky Monitor (WAM) which covers an energy range
of 50 keV - 5 MeV at UT 01:21:17.679 (=T0).
The observed light curve shows a single peak starting at T0+0.1 s,
ending at T0+0.4 s with a duration (T90) of about 0.25 seconds. The
fluence in 100 - 1000 keV was 1.48 (+1.67 / -0.99) x 10-6 erg/cm2.
The 1-s peak flux measured from T0+0 s was 1.4 (+0.4/-0.8)
photons/cm2/s in the same energy range.
Preliminary result shows that the time-averaged spectrum from T0+0 s to
T0+0.5 s is well fitted by a single power-law with a photon index of
2.17 (+0.53/-0.36) (chi2/d.o.f = 36.6/25).
All the quoted errors are at statistical 90% confidence level, in which
the systematic uncertainties are not included.
The light curves for this burst are available at:
http://www.astro.isas.jaxa.jp/suzaku/HXD-WAM/WAM-GRB/grb/trig/grb_table.html
GCN Circular 14671
Subject
GRB 130515A: IRSF NIR Observation
Date
2013-05-17T08:07:22Z (12 years ago)
From
Daisuke Kuroda at OAO/NAOJ <dikuroda@oao.nao.ac.jp>
Takahiro Nagayama (Nagoya Univ.) and Shogo Nishiyama (NAOJ)
on behalf of OISTER collaboration.
We observed the field of GRB 130515A (David Palmer, GCN Circular
14650) with the Infrared Survey Facility 1.4m telescope and
NIR camera SIRIUS (Nagayama et al., 2003) at Sutherland Observatory
in South Africa.
The observation was made with the JHKs bands simultaneously
from 2013-05-15 01:26 (UT), 5 minutes after the BAT trigger, to 04:41.
We have also detected the source detected by VLT (Dong Xu, GCN
Circular 14653) and GROND (Sebastian Schmidl, GCN Circular 14650)
at RA=18:53:45.79, DEC=-54:16:47.1 (J2000). Preliminary photometry
results are as follows
All combined images
(Total exposure time: 154 min, 2013-05-15 01:26 - 04:41)
J = 20.1 $B!^(B 0.2
H = 18.6 $B!^(B 0.2
Ks =18.7 $B!^(B 0.3
First 120 images
(Total exposure time: 60 min, 2013-05-15 01:26 - 2:45)
J = 19.4 $B!^(B 0.2
H = 18.9 $B!^(B 0.2
Ks: Non detection
These magnitudes are in the Vega system and not corrected for
Galactic extinction in the direction of the GRB.
GCN Circular 14670
Subject
GRB 130515A: Further Gemini Observations
Date
2013-05-16T23:23:55Z (12 years ago)
From
S. Bradley Cenko at Caltech <cenko@srl.caltech.edu>
S. B. Cenko (UC Berkeley) and A. Cucchiara (UCSC) report on behalf of a
larger collaboration:
We re-imaged the field of GRB 130515A (Malesani et al., GCN 14650) with
the Gemini Multi-Object Spectrograph mounted on the 8 m Gemini South
telescope. Images were obtained in the r' filter beginning at 4:38 UT on
2013 May 16 (~ 1.1 days after the Swift trigger).
Comparing with our previous epoch of observations (Cenko et al., GCN
14656), we find no evidence for variability in or around the enhanced XRT
error circle (Beardmore et al., GCN 14654). Specifically, we note that
the three sources S1, S2, and S3 identified previously (Xu et al., GCN
14653, Schmidl et al., GCN 14655, Levan et al., GCN 14677) all maintain a
constant brightness level. Using digital image subtraction, we limit the
optical afterglow at the time of our first epoch of observations (~ 38 min
after the Swift trigger) to be R > 23.7 mag (calibrated with respect to
nearby USNO-B1 point sources).
We thank the Gemini staff for the prompt execution of these observations.
GCN Circular 14668
Subject
Konus-Wind observation of GRB 130515A
Date
2013-05-16T10:01:58Z (12 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, E. Mazets, V. Pal'shin, D. Frederiks, P.
Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf of the Konus-Wind
team report:
The short-duration GRB 130515A (Swift-BAT trigger #555880:
Malesani et al., GCN 14650, Barthelmy et al., GCN 14658;
Fermi-GBM detection: Jenke, GCN 14663)
triggered Konus-Wind at T0=04880.440s UT (01:21:20.440)
The burst light curve shows a single pulse
from ~T0-0.05 s to ~T0-0.2 s, with a total duration of ~0.25s.
The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB130515_T04880/
As observed by Konus-Wind, the burst had a fluence
of (1.1 � 0.2)x10-6 erg/cm2 and a 16-ms peak flux,
measured from T0-0.016 s, of (2.1 � 0.5)x10-5 erg/cm2
(both in the 20 - 1500 keV energy range).
Modelling the K-W 3-channel time-integrated spectrum
(from T0-0.064 s to T0+0.192 s)
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = 0.0 � 0.4, and Ep = 410 � 90 keV
Modelling the K-W 3-channel spectrum at the maximum count rate
(from T0-0.064 s to T0)
by a power law with exponential cutoff model
yields alpha = -0.5 � 0.4, and Ep = 715 � 360 keV
All the quoted errors are at the 1 sigma confidence level.
GCN Circular 14667
Subject
GRB 130515A: FORS2 spectroscopy of candidate counterpart
Date
2013-05-16T09:04:17Z (12 years ago)
From
Nial Tanvir at U.Leicester <nrt3@star.le.ac.uk>
A. J. Levan (U. Warwick) and N. R. Tanvir (U. Leicester) report for a larger collaboration:
We observed the location of GRB 130515A (Malesani et al. GCN 14650) with VLT/FORS2, beginning at ~03:30 UT, 2 hours after the burst. At this epoch we obtained imaging and spectroscopy of the brightest source in the XRT error box (S1 in Xu et al. GCN 14653 and Cenko et al. GCN 14656). This spectrum exhibits several broad absorption features consistent with an M-dwarf star at z=0, indicating that it is not the host galaxy of GRB 130515A.
In fact, preliminary analysis of our imaging suggests that sources S2 and S3 referred to by Xu et al. and Cenko et al. are also consistent with being point-like. The nearest evidently extended, and reasonably bright, source is a galaxy at position 18:53:45.01 -54:16:50.9, approximately 8 arcsec from the current enhanced X-ray position (http://www.swift.ac.uk/xrt_positions/00555880/).
We thank the staff at Paranal for their excellent support with these observations.
GCN Circular 14663
Subject
GRB 130515A: Fermi GBM detection
Date
2013-05-15T17:16:56Z (12 years ago)
From
Peter Jenke at MSFC <peter.a.jenke@nasa.gov>
P. Jenke (UAH) reports on behalf of the Fermi GBM Team:
"At 01:21:17.88 UT on May 15 2013, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 130515A (trigger 390273680 / 130515056),
which was also detected by the Swift/BAT (Malesani et al., GCN Circ. 14650).
The GBM on-ground location is consistent with the Swift position.
The angle of the Fermi LAT boresight is 120 degrees from the Swift location.
The GBM light curve consists of a single pulse with a FRED-like shape
with a duration (T90) of about 0.26 s (50-300 keV).
The time-averaged spectrum from T0-0.064 s to T0+0.256 s is
well fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.90 +/- 0.08 and
the cutoff energy, parameterized as Epeak, is 450 +/- 100 keV.
The event fluence (10-1000 keV) in this time interval is
(10.4 +/- 0.5)E-07 erg/cm^2. The 0.064-sec peak photon flux measured
starting from T0+0.0 s in the 10-1000 keV band
is 22 +/- 2 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog."
GCN Circular 14661
Subject
GRB 130515A: Swift-XRT refined Analysis
Date
2013-05-15T16:11:31Z (13 years ago)
From
Binbin Zhang at PSU <bbzhang@psu.edu>
B.-B. Zhang (PSU) and D. Malesani (DARK/NBI) report on behalf of the
Swift-XRT team:
We have analysed 8.1 ks of XRT data for GRB 130515A (Malesani et al.
GCN Circ. 14650), from 82 s to 34.1 ks after the BAT trigger. The
data are entirely in Photon Counting (PC) mode. The enhanced XRT
position for this burst was given by Beardmore et al. (GCN. Circ
14654). The source is fading with alpha >0.8.
If the light curve continues to decay with a power-law decay index of 0.8,
the count rate at T+24 hours will be 1.4 x 10^-4 count s^-1
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00555880.
This circular is an official product of the Swift-XRT team.
[GCN OPS NOTE(15may13): Per author's request, the ).8" was added
to the end of the first line in the 2nd paragraph.]
GCN Circular 14660
Subject
GRB 130515A: Swift/UVOT Upper Limits
Date
2013-05-15T14:16:02Z (13 years ago)
From
Samantha Oates at MSSL <sro@mssl.ucl.ac.uk>
S. R. Oates (MSSL-UCL), M. De Pasquale (MSSL-UCL) and D. Malesani (DARK/NBI)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 130515A
79 s after the BAT trigger (Malesani et al., GCN Circ. 14650).
In the intial UVOT exposures, we do not detect an optical afterglow consistent
with the refined XRT position (Beardmore et al. GCN Circ. 14654). We also do not
detect an optical source consistent with the positions of s1 and s2 reported by the VLT
(Xu et al. GCN Circ. 14653) and Gemini (Cenko et al., GCN Circ. 14656),
nor at the positions of the sources reported by GROND (Schmidl et al., GCN Circ. 14655).
However, we do marginally detect VLT s3 (Xu et al. GCN Circ. 14653) in white
at a magnitude of 21.59 +/- 0.39, which is also observed in the DSS.
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 at the refined
XRT position are:
Filter T_start(s) T_stop(s) Exp(s) Mag
white_FC 79 229 147 >21.2
u_FC 291 541 246 >20.2
white 79 6414 580 >21.7
v 620 5388 236 >19.8
b 546 6209 432 >21.0
u 291 6003 659 >20.7
w1 669 5798 413 >20.7
m2 645 5592 236 >20.0
w2 596 6603 415 >20.7
The magnitudes in the table are not corrected for the
Galactic extinction due to the reddening of E(B-V) = 0.07
in the direction of the burst (Schlegel et al. 1998).
GCN Circular 14658
Subject
GRB 130515A: Swift-BAT refined analysis
Date
2013-05-15T11:57:33Z (13 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
S. D. Barthelmy (GSFC), W. H. Baumgartner (GSFC/UMBC), J. R. Cummings (GSFC/UMBC),
E. E. Fenimore (LANL), N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA),
A. Y. Lien (NASA/GSFC/ORAU), C. B. Markwardt (GSFC), D. Malesani (DARK/NBI),
D. M. Palmer (LANL), 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-60 to T+243 sec from recent telemetry downlinks,
we report further analysis of BAT GRB 130515A (trigger #555880)
(Malesani, et al., GCN Circ. 14650). The BAT ground-calculated position is
RA, Dec = 283.436, -54.283 deg, which is
RA(J2000) = 18h 53m 44.6s
Dec(J2000) = -54d 16' 57.3"
with an uncertainty of 1.6 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 69%.
The mask-weighted light curve shows two overlapping peaks starting
at ~T+0.00, peaking at ~T+0.00 and ~T+0.30, and ending at ~T+0.40 sec.
T90 (15-350 keV) is 0.29 +- 0.06 sec (estimated error including systematics).
The time-averaged spectrum from T-0.04 to T+0.33 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
0.77 +- 0.18. The fluence in the 15-150 keV band is 1.5 +- 0.2 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.35 sec in the 15-150 keV band
is 1.4 +- 0.2 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/555880/BA/
GCN Circular 14656
Subject
GRB 130515A: Gemini/GMOS Observations
Date
2013-05-15T06:32:58Z (13 years ago)
From
S. Bradley Cenko at Caltech <cenko@srl.caltech.edu>
S. B. Cenko (UC Berkeley), A Cucchiara (UCSC), D. Xu (DARK/NBI), and A. J.
Levan (U. Warwick) report on behalf of a larger collaboration:
We obtained a single 240 s r'-band image of the field of GRB 130515A
(Malesani et al., GCN 14650) with the Gemini Multi-Object Spectrograph
mounted on the 8 m Gemini South telescope. The observation commenced at
01:59 UT (~ 38 min after the Swift trigger) under poor seeing conditions.
We identify the same 3 sources in the vicinity of the XRT error circle as
Xu et al. (GCN 14653). For reference, we measure J2000.0 positions for
these sources with respect to nearby point sources from the 2MASS catalog
to be:
S1: 18:53:45.79, -54:16:47.1
S2: 18:53:45.23, -54: 16:44.4
S3: 18:53:46.13, -54:16:41.2
We have compared photometry from our Gemini images directly with that
obtained by the VLT approximately 50 minutes later. For these three point
sources, we measure the following change in magnitude (VLT - Gemini):
S1: -0.37 +/- 0.18 mag
S2: -0.03 +/- 0.10 mag
S3: -0.03 +/- 0.10 mag
There is this marginal evidence that S1 has brightened between the two
epochs. However, we cannot rule out that the discrepancy results from a
color difference between the two images (r' vs R).
Further observations are planned.
[GCN OPS NOTE(15may13): Per author's request, the 14653 reference was
corrected to "Xu et al".]
GCN Circular 14655
Subject
GRB 130515A: GROND Observations
Date
2013-05-15T06:01:37Z (13 years ago)
From
Sebastian Schmidl at TLS Tautenburg <schmidl@tls-tautenburg.de>
S. Schmidl, D. A. Kann (both TLS Tautenburg) and J. Greiner (MPE Garching)
report on behalf of the GROND team:
We observed the field of the short GRB 130515A (Swift trigger 555880;
Malesani et al., GCN 14650) simultaneously in g'r'i'z'JHKs with GROND
(Greiner et al. 2008, PASP 120, 405) mounted at the 2.2 m MPG/ESO
telescope at La Silla Observatory (Chile).
Observations started as soon as the position became visible above the
pointing limit, at 02:12:08 UT on May 15th, 51 minutes after the BAT
trigger. They were performed at an average seeing of 1".6 and at an
average airmass of 2.4.
Inside the 2".9 SPER XRT error circle (RA = 18:53:45.79, Dec.
-54:16:45.2), we detect a faint source, and additionally a significantly
brighter, possibly extended source on the western edge of the XRT error
circle.
We find the following positions (J2000) for these sources:
In the error circle: RA = 18:53:45.79, Dec. = -54:16:47.3
On the western edge: RA = 18:53:45.24, Dec. = -54:16:44.5
with an error of 0".5 in each case.
Based on an observation with 780 s integration time in g'r'i'z' and 720 s
integration time in JHK, centered at 0.043586 days after the trigger, we
estimate preliminary magnitudes 3-sigma upper limits (all in AB system) of
g' > 23.86,
r' = 22.55 +/- 0.15,
z' = 21.17 +/- 0.11,
J = 19.74 +/- 0.27,
H > 19.4 and
K > 19.1
for the object inside the error circle, and
g' = 22.12 +/- 0.08.,
r' = 20.68 +/- 0.03.,
z' = 19.51 +/- 0.03.,
J = 18.50 +/- 0.09,
H = 18.45 +/- 0.14 and
K = 18.47 +/- 0.17
for the possible galaxy on the western edge.
Given magnitudes are calibrated against GROND zero points (g'r'i'z') as
well as 2MASS field stars (JHK) and are not corrected for the expected
Galactic foreground extinction corresponding to a reddening of
E_(B-V)=0.07 mag in the direction of the burst (Schlegel et al. 1998).
GCN Circular 14654
Subject
GRB 130515A: Enhanced Swift-XRT position
Date
2013-05-15T05:59:47Z (13 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
A.P. Beardmore, P.A. Evans, M.R. Goad and J.P. Osborne (U. Leicester)
report on behalf of the Swift-XRT team.
Using 719 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 130515A, 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 = 283.44011, -54.27906 which is equivalent
to:
RA (J2000): 18h 53m 45.63s
Dec (J2000): -54d 16' 44.6"
with an uncertainty of 2.4 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 14653
Subject
GRB 130515A: VLT acquisition observation
Date
2013-05-15T04:39:26Z (13 years ago)
From
Dong Xu at DARK/NBI <dong.dark@gmail.com>
Dong Xu (DARK/NBI), Andrew J. Levan (Univ. Warwick), Nial R. Tanvir
(Univ. Leicester), Daniele Malesani (DARK/NBI), Johan P. U. Fynbo
(DARK/NBI), Steve Schulze (PUC and MCSS), report on behalf of the
X-shooter GRB GTO collaboration:
We observed the field of the short GRB 130515A (Malesani et al., GCN
14650) with the ESO VLT equipped with X-shooter.
In a 30-s acquisition image taken in the R band starting at 2:49 UT
(1.46 hr after the GRB), we detect a single source S1 consistent with
the best currently available XRT position
(http://www.swift.ac.uk/xrt_positions/), at coordinates (J2000):
(S1)
RA = 18:53:45.82
Dec = -54:16:46.9
This source has a magnitude R ~ 21.2, and can be faintly glimpsed in
the DSS red. At the present time, we cannot assess its relation to the
GRB, though it may be the host galaxy.
We also note the presence of two further objects S2 and S3 just
outside the XRT error circle, which can also be seen in the DSS, at
coordinates:
(S1)
RA = 18:53:45.26
Dec = -54:16:44.3
(S2)
RA = 18:53:46.16
Dec = -54:16:41.1
We acknowledge excellent and prompt support from the observing staff
at Paranal, in particular Grant Tremblay.
GCN Circular 14650
Subject
GRB 130515A: Swift detection of a short burst
Date
2013-05-15T01:35:00Z (13 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
D. Malesani (DARK/NBI), S. D. Barthelmy (GSFC),
N. Gehrels (NASA/GSFC), D. Grupe (PSU), S. T. Holland (STScI),
J. A. Kennea (PSU), C. B. Markwardt (NASA/GSFC), D. M. Palmer (LANL),
B. Sbarufatti (INAF-OAB/PSU), M. H. Siegel (PSU), C. A. Swenson (PSU),
T. N. Ukwatta (MSU) and B.-B. Zhang (PSU) report on behalf of the
Swift Team:
At 01:21:17 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 130515A (trigger=555880). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 283.422, -54.281 which is
RA(J2000) = 18h 53m 41s
Dec(J2000) = -54d 16' 51"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a single
short peak with a duration of about 0.6 sec. The peak count rate
was ~13000 counts/sec (15-350 keV), at ~0.1 sec after the trigger.
The XRT began observing the field at 01:22:32.9 UT, 75.2 seconds after
the BAT trigger. Using promptly downlinked data we find a faint uncatalogued
X-ray source with an enhanced position: RA, Dec 283.4405, -54.2794
which is equivalent to:
RA(J2000) = 18h 53m 45.72s
Dec(J2000) = -54d 16' 45.9"
with an uncertainty of 3.1 arcseconds (radius, 90% containment). This
location is 39 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 5.79
x 10^20 cm^-2 (Kalberla et al. 2005).
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 78 seconds after the BAT trigger. No credible afterglow candidate has
been found in the initial data products. The 2.7'x2.7' sub-image covers 100% of
the XRT error circle. The typical 3-sigma upper limit has been about 19.6 mag.
The 8'x8' region for the list of sources generated on-board covers 100% of the
XRT error circle. The list of sources is typically complete to about 18 mag. No
correction has been made for the expected extinction corresponding to E(B-V) of
0.07.
Burst Advocate for this burst is D. Malesani (malesani AT dark-cosmology.dk).
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.)