GRB 150710A
GCN Circular 18001
Subject
GRB 150710A: RATIR Observations
Date
2015-07-10T04:58:33Z (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), Chris Klein (UCB), Ori Fox (UCB),
J. Xavier Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara
(ORAU/GSFC), 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), and
Harvey Moseley (GSFC) report:
We observed the field of possible GRB 150710A (trigger 648437; Bernardini,
et al., GCN 18000) 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 2015/07
10.16 to 2015/07 10.20 UTC (3.47 to 4.31 hours after the BAT trigger),
obtaining a total of 0.71 hours exposure in the r, i, and z bands.
For a source within the Swift-XRT error circle, in comparison with the SDSS
DR9 catalog, we obtain the following upper limits (3-sigma):
r > 23.4
i > 23.2
z > 19.4
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the possible GRB.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir. Further observations are ongoing.
GCN Circular 18002
Subject
GRB 150710A: Swift-BAT refined analysis
Date
2015-07-10T13:52:31Z (10 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@lheamail.gsfc.nasa.gov>
S. D. Barthelmy (GSFC), M. G. Bernardini (INAF-OAB), J. R. Cummings (GSFC/UMBC),
N. Gehrels (GSFC), H. A. Krimm (GSFC/USRA), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), D. M. Palmer (LANL), T. Sakamoto (AGU),
M. Stamatikos (OSU), T. N. Ukwatta (LANL)
(i.e. the Swift-BAT team):
Using the data set from T-61 to T+242 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 150710A (trigger #648437)
(Bernardini, et al., GCN Circ. 18000). The BAT ground-calculated position is
RA, Dec = 194.484, 14.309 deg, which is
RA(J2000) = 12h 57m 56.3s
Dec(J2000) = +14d 18' 32.3"
with an uncertainty of 1.5 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 100%.
The mask-weighted light curve shows two, possibly 4, overlapping peaks.
T90 (15-350 keV) is 0.15 +- 0.06 sec (estimated error including systematics).
The time-averaged spectrum from T+0.02 to T+0.22 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
0.63 +- 0.20. The fluence in the 15-150 keV band is 7.1 +- 0.9 x 10^-8 erg/cm2.
The 1-sec peak photon flux measured from T-0.38 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.
These results are entirely consistant with a short GRB.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/648437/BA/
GCN Circular 18003
Subject
Konus-Wind observation of GRB 150710A (Swift trigger 648437)
Date
2015-07-10T13:58:12Z (10 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
S. Golenetskii, R.Aptekar, D. Frederiks, V. Pal'shin, P. Oleynik,
M. Ulanov, D. Svinkin, A. Tsvetkova, A.Lysenko, and T. Cline
on behalf of the Konus-Wind team, report:
The short-duration GRB 150710A (Swift trigger 648437:
Bernardini, et al., GCN Circ. 18000) triggered Konus-Wind
at T0=1681.682 s UT (00:28:01.682).
The burst light curve shows a short, double-peaked pulse with
a total duration of ~0.1 s.
As observed by Konus-Wind, the burst had a fluence of
(3.7 �� 0.7)x10^-7 erg/cm2, and a 16-ms peak flux,
measured from T0-0.048 s, of (7.6 �� 1.5)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
Since the bulk of the burst emission was detected before
the trigger, the spectral analysis was performed using
the KW 3-channel light curve data.
Modeling the 3-channel time-integrated spectrum
(from T0-0.048 s to T0+0.048 s) by a power law
with exponential cutoff (CPL) model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
yields alpha = -0.28 �� 0.54, and Ep = 308 �� 70 keV.
The K-W light curve of this burst is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB150710_T01681/
Following Bernardini, et al. (GCN Circ. 18000),
we note, that the burst, as observed by Konus-Wind,
is comparable in hardness and other aspects to a typical
short GRB from the KW sample.
The figure showing the GRB 150710A position in the hardness-duration
diagram (logT50-logHR32) of 1143 KW bright GRBs is available at
http://www.ioffe.rssi.ru/LEA/GRBs/GRB150710_T01681/HR32vsT50.png
The contours denote the 1, 2, and 3 sigma confidence regions for
two-dimensional Gaussian distributions. The vertical dashed line at
T50=0.6 s marks the boundary between short and long KW GRBs.
All the quoted errors are estimated at the 1 sigma confidence level.
All the presented results are preliminary.
GCN Circular 18005
Subject
Swift-XRT observations of GRB 150710A
Date
2015-07-10T18:09:11Z (10 years ago)
From
Maria Grazia Bernardini at INAF/Brera <grazia.bernardini@brera.inaf.it>
M.G. Bernardini, P. D'Avanzo, A. Melandri, S. Campana,
G. Tagliaferri (INAF-OAB), D. Burrows (PSU), K. Page
and P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:
We analyzed the full dataset of Swift-XRT observations of the
Swift trigger 648437 (Bernardini et al., GCN Circ. 18000),
classified as short GRB 150710A (Barthelmy et al., GCN Circ.
18002, Golenetskii et al. GCN Circ. 18003), comprising 11.2 ks in
Photon Counting (PC) mode. One X-ray source has been detected
within the BAT error circle at the following position:
RA (J2000.0): 194.47045 = 12:57:52.91
Dec (J2000.0): 14.31807 = +14:19:05.0
Error: 2.8 arcsec (radius, 90% conf.)
This position is consistent with the location of a ROSAT faint source
1RXS J125754.7+14185. In an initial 0.98 ks observation carried out
between T+57s and T+1056s, the source has an initial count-rate of
(3.22E-02 �� 6.3E-03) ct/s. Then in a subsequent 10 ks observation,
carried out between T+4.9 ks and T+34.5 ks, it is no longer detected
down to a 3sigma UL of 1.3E-3 ct/s. The source is near the edge of
the Virgo cluster, but the non-detection of any host galaxy by RATIR
(Butler et al., GCN Circ. 18001) argues against the possibility of this
being a giant SGR flare from a galaxy in the Virgo cluster. Given the
observed fading, we propose this source as the X-ray counterpart of
GRB 150710A.
We also note the possible presence of a second source at the following
position:
RA (J2000.0): 194.4810088073 = 12:57:55.44
Dec (J2000.0): 14.317574983 = +14:19:03.3
Error: 6.0 arcsec (radius, 90% conf.)
also consistent with the location of 1RXS J125754.7+14185. The source
is detected at a low significance, and it is not possible with present data
to assess if is real or not. Further observation can confirm if this second
source is real and if it is possibly related to 1RXS J125754.7+14185.
Otherwise, we cannot exclude that the observed X-ray emission from
Source #1 is due to a brightening from 1RXS J125754.7+14185.
This circular is an official product of the Swift-XRT team.
GCN Circular 18006
Subject
GRB 150710A: host galaxy for Swift XRT second candidate
Date
2015-07-10T19:18:38Z (10 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov (Lomonosov Moscow State University)
There is SDSS9 galaxy at second XRT candidate postion (Bernardini et al.,
GCN 18005) J125755.36+141905.7 .
Rmag = 22.1, gmag = 24
That is correspond to z ~ 1 for big galaxy like to Milky Way.
The follow up observation for redshift is needed.
The message may be cited.
GCN Circular 18008
Subject
GRB 150710A: Swift/UVOT Upper Limits
Date
2015-07-10T20:15:24Z (10 years ago)
From
Massimiliano de Pasquale at IASF-Palermo <m.depasquale@ucl.ac.uk>
M. De Pasquale (UCL-MSSL) and M.G. Bernardini (INAF/OAB)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 150710A
54 s after the BAT trigger (Bernardini et al., GCN Circ. 18000).
No optical afterglow consistent with the position of the XRT sources
(Bernardini et al., GCN Circ 18005) 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 54 204 147 >20.6
u_FC 266 516 246 >19.9
white 54 1017 334 >21.1
v 595 1050 41 >18.1
b 521 714 39 >19.1
u 266 516 285 >20.0
uw1 645 837 39 >18.5
um2 620 812 39 >18.2
uw2 571 1043 58 >19.0
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.03 in the direction of the burst
(Schlegel et al. 1998).