GRB 160816A
GCN Circular 19892
Subject
GRB 160816A: Possible radio afterglow detection at 15 GHz with AMI
Date
2016-09-05T20:21:51Z (9 years ago)
From
Kunal Mooley at Oxford U <kunal.mooley@physics.ox.ac.uk>
K. P. Mooley, T. D. Staley, R. P. Fender (Oxford), G. E. Anderson
(Curtin), T. Cantwell (Manchester), C. Rumsey, D. Titterington, S. H.
Carey, J. Hickish, Y. C. Perrott, N. Razavi-Ghods, P. Scott (Cambridge),
K. Grainge, A. Scaife (Manchester)
We observed the Fermi/LAT GRB 160816A (Racusin et al., GCN 19802) with
the AMI Large Array at 15 GHz on 2016 Aug 18.02, Aug 19.06, and Sep
03.02 (UT) as part of the 4pisky program. We detect a possible radio
afterglow (consistent with the XRT location; Kennea et al., GCN 19806)
in the second epoch with a peak flux density of 129+/-32 uJy, and 3sigma
upper limits of 111 uJy and 168 uJy in the first and third epochs
respectively.
We thank the AMI staff for scheduling these observations. The AMI-GRB
database is a log of all GRB follow up observations with the AMI, and is
available at http://4pisky.org/ami-grb/.
GCN Circular 19881
Subject
GRB 160816A, the review of the sky area in plate archives
Date
2016-08-29T20:55:56Z (9 years ago)
From
Valentyna Golovnya at Main Astro Obs,Kyiv <golov_v@ukr.net>
V.V. Golovnya, V.M. Andruk (Main Astro Obs., Kyiv) report: We have undertaken the review of the sky area in vicinity of GRB 160816A (Kennea J.A. et al., GCN 19806) on astronegatives, collected in Ukrainian NAS Main astronomical observatory plate archives (1976-1996). All the plates with the possible object appearance are digitized using Epson Expression 10000XL flatbed scanner and have been placed into Golosiiv Plate Archive database DBGPA with open access to them. �������������� The list of plates is given in the table: YYYYMMDD/TimeUT --Plates--�������� Exp.������ Bmag������ Star USNO-A2 19 850822/212139 GUA040C000726�� 18.0������ 16.2������ 1200-18040986 19860712/234442 GUA040C000958�� 16.0������ 16.0������ 1200-18048101 19 860713/000658 GUA040C000959A 16.0������ 16.1������ 1200-18044684 19 860716/233422 GUA040C000967�� 16.0������ 16.6������ 1200-18046182 19 860716/235509 GUA040C000968A 16.0������ 16.6������ 1200-18046182 TimeUT ��� T start of the maximum exposure; Plates - The plates archive identifier of DWA (D/F=40/200,M=103"/mm) GUA040C, of the Ukrainian NAS Main Astro obs, Marsden's number - 83) the plate number (http://gua.db.ukr-vo.org). Exp.�� - Duration of the maximum exposure (minutes). Bmag�� - Limited B mag, derived in the 6 minutes area around ������������ the location GRB 160816A given in P.A. Evans (P. Evans http://www.swift.ac.uk/xrt_positions/00020685/): ������������ RA(J2000)= 21h 29m 38.71s, Dec(J2000)= +37d 07' 58.3" Star USNO-A2 - Comparison star. ��The preview images of 5 areas together with the 6 min.of arc area from Aladin can be found in http://gua.db.ukr-vo.org/img/grb/160816A/index.html. The images with full resolution are available via e-mail on demand.
GCN Circular 19829
Subject
GRB 160816A: TSHAO optical observations
Date
2016-08-21T13:37:01Z (9 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), I. Reva (Fesenkov Astrophysical Institute), A. Kusakin
(Fesenkov Astrophysical Institute), A. Volnova (IKI), A. Pozanenko
(IKI) report on behalf of larger GRB follow-up collaboration:
We observed the field of 160816A (Racusin et al., GCN 19802; Mailyan et
al., GCN 19804) with Zeiss-1000 (East) 1-m telescope of Tien Shan
Astronomical Observatory. We obtained several images in R filter
starting on August 17 and 18. We detected optical afterglow (Guidorzi
et al. GCN 19808; Troja et al. GCN 19809) on Aug. 17 and obtained upper
limit on Aug. 18. Preliminary photometry of a combined image is following
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2016-08-17 21:32:28 1.19553 R 105*30 21.70 0.20 21.9
2016-08-18 19:11:47 2.11663 R 148*30 n/d n/d 22.1
Photometry is based on nearby USNO-B1.0 stars
USNO-B1.0_id R2
1271-0576219 17.27
1271-0576200 17.52
1271-0576190 18.12
1271-0576101 17.00
GCN Circular 19825
Subject
GRB 160816A: ISON/UAFO optical observations
Date
2016-08-19T15:34:50Z (9 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), E. Chornaya (UAFO, ISON), A. Matkin (UAFO), I.
Molotov (KIAM), A. Pozanenko (IKI) report on behalf of larger GRB
follow-up collaboration:
We observed the field of GRB 160816A (Racusin et al., GCN 19802;
Mailyan et al., GCN 19804) with SANTEL-650 (0.65m) telescope of
UAFO/ISON-Ussuriysk observatory. We obtained several unfiltered images
starting on August 17 (UT) 11:47:34. We detected optical afterglow
(Guidorzi et al. GCN 19808; Troja et al. GCN 19809). Preliminary
photometry of a combined image is following
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2016-08-17 11:47:34 0.80873 CR 275*20 20.90 0.22 21.5
Photometry is based on nearby USNO-B1.0 stars
USNO-B1.0_id R2
1271-0576219 17.27
1271-0576200 17.52
1271-0576190 18.12
1271-0576101 17.00
1271-0576308 17.05
GCN Circular 19824
Subject
GRB 160816A: Further RATIR Optical and NIR Observations
Date
2016-08-19T14:22:23Z (9 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 (UVI), 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 the Fermi GRB 160816A (Mailyan, et al.,
GCN 19804) 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 2016/08 19.16 to 2016/08 19.50 UTC (2.43 to 2.77 days after
the GBM trigger), obtaining a total of 5.58 hours exposure in the
r and i bands and 4.56 hours exposure in the Z and J bands.
For the source reported in Troja, et al. (GCN 19809), in comparison
with the USNO-B1 and 2MASS catalogs, we obtain the following
detections:
r 23.45 +/- 0.15
i 23.18 +/- 0.12
Z 22.64 +/- 0.12
J 22.37 +/- 0.16
These magnitudes are in the AB system and 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.
GCN Circular 19821
Subject
GRB 160816A: MASTER OT early detection on coaded images
Date
2016-08-18T16:25:19Z (9 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
N.Tyurina, E. Gorbovskoy, V. Lipunov, V.Kornilov,
P.Balanutsa, A.Kuznetsov, D.Kuvshinov
Lomonosov Moscow State University, Sternberg Astronomical Institute
R. Rebolo, M. Serra, N. Lodieu, G. Israelian
The Instituto de Astrofisica de Canarias
K.Ivanov, O.Gres, N.M.Budnev, S.Yazev,
Irkutsk State University
D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory
A. Tlatov, V.Senik, D. Dormidontov, A.Parkhomenko
Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, A.Gabovich
Blagoveschensk Educational State University, Blagoveschensk
Hugo Levato, Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
R.Podesta, C.Mallamaci, C.Lopez, F. Podesta
Observatorio Astronomico Felix Aguilar (OAFA)
MASTER II robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in IAC was pointed to the GRB160816.73 24 sec after notice time
and 18726 sec after trigger time at 2016-08-16 22:43:04 UT. (We corrected
start exposition time which published in previouse MASTER circular
(Lipunov et al., GCN 19805). We reducted coadded images and found OT.
We see OT on coadded images inside SWIFT XRT (Kennea et al., GCN19806) at
LCOGT position (Guidorzi et al., GCN 19808, Kuin et al., GCN 19815) on two
tubes with unfiltered magnitude calibrated by USNO B1 stars ( m =
0.2B+0.8R ):
m_OT=20.5 (+0.5 -0.2) at mean exposition time 2016-08-16 23:05:53,
20095 sec (5.58 hours) after GBM trigger time. T_start =18762sec,
T_end=21464
after
trigger. The total exposition = 1800 sec.
The images is available at
http://observ.pereplet.ru/images/GRB160816AMASTER.jpg
The message may be cited.
GCN Circular 19820
Subject
GRB 160816A: RATIR Optical and NIR Afterglow Confirmation
Date
2016-08-18T12:35:04Z (9 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), 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 160816A (Mailyan, et al., GCN 19804;
Racusin, et al., GCN 19802) 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 2016/08 18.17 to 2016/08 18.47 UTC (1.44 to
1.72 days after the GBM trigger), obtaining a total of 2.47 hours
exposure in the r and i bands and 1.03 hours exposure in the Z,
Y, J, and H bands.
For the source reported in Troja, et al. (GCN 19809), in comparison
with the USNO-B1 and 2MASS catalogs, we obtain the following
detections and upper limit (3-sigma):
r 22.74 +/- 0.15
i 22.40 +/- 0.12
Z 22.19 +/- 0.19
Y 22.18 +/- 0.25
J > 22.32
H 21.20 +/- 0.18
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB.
The source intensity decreased significantly between our two epochs,
corresponding to fading with power-law index alpha~-1.3 referenced to
the burst trigger. This confirms that the candidate reported by
Guidorzi, et al. (GCN 19808) and Troja et al. (GCN 19809) is the GRB
afterglow.
Deep imaging of the GRB location reveals additional optical sources
within the XRT localization (Kennea et al., GCN 19806), however none of
them have faded.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 19819
Subject
GRB 160816A: confirmed fading with the LT
Date
2016-08-18T12:23:22Z (9 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), S. Kobayashi, I.A. Steele (LJMU), C.G. Mundell
(U. Bath), A. Gomboc (U. Nova Gorica), N. Tanvir (U. Leicester) on
behalf of a large collaboration report:
The 2-m Liverpool Telescope observed GRB 160816A from August 17, 23:29
UT to August 18, 02:44 UT with a total net exposure of 600 s in both
SDSS-R and SDSS-I filters. The optical afterglow candidate (Guidorzi et
al. GCN 19808; Troja et al. GCN 19809; Kuin et al. GCN 19815) has faded
to r=21.8 +- 0.2 mag at 1.3 days post burst, compatibly with an average
power-law decay index alpha~1.
GCN Circular 19818
Subject
GRB 160816A iTelescope observation
Date
2016-08-18T03:00:05Z (9 years ago)
From
Takanori Sakamoto at AGU <tsakamoto@phys.aoyama.ac.jp>
Y. Kitaoka, T. Sakamoto, A. Yoshida (AGU)
We observed the field of GRB 160816A detected by Fermi (Racusin et al.,
GCN Circ. 19802) with the iTelescope.Net (http://www.itelescope.net) T7
(17" Plane Wave) telescope located at the AstroCamp Observatory (Nerpio, Spain).
15 images of 60 sec exposures were taken in the R filter starting from
August 16 22:50:57 (UT) about 5.9 hours after the trigger and stopped on
August 16 23:26:36 (UT). We do not detect the optical afterglow both in the
individual images and the stacked image at the X-ray afterglow position
(Kennea et al., GCN Circ. 19806). 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 19815
Subject
GRB 160816A: Swift/UVOT Detection
Date
2016-08-17T19:29:32Z (9 years ago)
From
Paul Kuin at MSSL <npkuin@gmail.com>
Paul Kuin (UCL/MSSL), D. Malesani (DARK/NBI and DTU Space), Frank
Marshall (GSFC) and Lea Hagen (PSU) report on behalf of the Swift/UVOT
team:
The Swift/UVOT began settled observations of the field of the Fermi/LAT-
detected GRB 160816A 25222 s after the LAT trigger (Racusin et al. GCN
Circ. 19802). A source consistent with the XRT position (Kennea et al.
GCN Circ. 19806) and the LCOGT Faulkes Telescope North position (Guidorzi
et al., GCN Circ. 19808) is detected in the initial UVOT exposures at the
same position as reported by RATIR (Troja et al, GCN. Circ. 19809).
Preliminary detections and 3-sigma upper limit 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 27601 43846 879 21.48 +/- 0.22
v 27661 27703 41 >17.9
u 25222 37523 2287 21.37 +/- 0.31
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.25 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 19814
Subject
GRB 160816A: IPN annulus
Date
2016-08-17T18:17:28Z (9 years ago)
From
Kevin Hurley at UCBerkeley/SSL <khurley@ssl.berkeley.edu>
K. Hurley, on behalf of the IPN,
I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,
W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr, on
behalf of the GRS-Odyssey GRB team,
S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
D. Svinkin, and T. Cline, on behalf of the Konus-Wind team, and
V. Connaughton, M. S. Briggs, C. Meegan, V. Pelassa, and A. Goldstein,
on behalf of the Fermi GBM team, report:
GRB 160816A has been observed by Konus-Wind (GCN 19810), Fermi GBM and LAT
(GCN 19804, GCN 19802), and Mars Odyssey-HEND, so far. We have triangulated
it to a preliminary annulus centered at RA, Dec (2000)=63.3328, 24.0531 degrees,
with radius 83.8027 +/- 0.1087 degrees (3 sigma). The center line of the annulus passes 0.0086 degrees
from the Swift XRT source (GCN 19806), supporting the conclusion that this source
is the GRB afterglow. A map has been posted at ssl.berkeley.edu/ipn3/160816A.
GCN Circular 19810
Subject
Konus-Wind observation of GRB 160816A
Date
2016-08-17T13:32:53Z (9 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, P. Oleynik,
M. Ulanov, A. Tsvetkova, A. Lysenko, A. Kozlova, and T. Cline
on behalf of the Konus-Wind team, report:
The long-duration, very intense, GRB 160816A
(Fermi LAT detection: Racusin et al., GCN Circ. 19802;
Fermi GBM observation: Mailyan and Meegan, GCN Circ. 19804)
triggered Konus-Wind at T0=63061.653 s UT (17:31:01.653).
The burst light curve shows a multipeaked structure
started at ~T0 with a total duration of ~14 s.
The emission is seen up to 3 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160816_T63061/
As observed by Konus-Wind, the burst
had a fluence of 3.16(-0.10,+0.11)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+8.032 s,
of 1.63(-0.16,+0.16)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+19.712 s)
is best fit in the 20 keV - 3 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.81(-0.06,+0.06)
and Ep = 239(-11,+12) keV (chi2 = 51/68 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -3.0
(chi2 = 49/67 dof)
The spectrum near the maximum count rate
(measured from T0+2.304 to T0+8.448 s)
is best fit in the 20 keV - 3 MeV range
by a power law with exponential cutoff model
with alpha = -0.89(-0.08,+0.09)
and Ep = 244(-18,+20) keV (chi2 = 66/68 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -3.2
(chi2 = 66/67 dof)
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
GCN Circular 19809
Subject
GRB 160816A: RATIR Optical and NIR Observations
Date
2016-08-17T09:26:10Z (9 years ago)
From
Eleonora Troja at GSFC <eleonora.troja@nasa.gov>
Eleonora Troja (GSFC), Alan M. Watson (UNAM), Nat Butler (ASU),
Alexander Kutyrev (GSFC), William H. Lee (UNAM), Michael G.
Richer (UNAM), Ori Fox (STScI), J. Xavier Prochaska (UCSC),
Josh Bloom (UCB), Antonino Cucchiara (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 the Fermi GRB 160816A (Mailyan, et al.,
GCN 19804; Racusin et al. 19802) 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 2017-08-17 06:15 to 07:44 UTC (12.8 to 14.2 hours after
the GBM trigger), obtaining a total of 0.71 hours exposure in the r
and i bands and 0.30 hours exposure in the Z, Y, J, and H bands.
For a source within the Swift/XRT error circle (Kennea et al., GCN 19806),
in comparison with the USNO-B1 and 2MASS catalogs, we obtain the
following detections:
r = 21.05 +/- 0.05
i = 20.79 +/- 0.04
Z = 20.61 +/- 0.07
Y = 20.32 +/- 0.08
J = 20.16 +/- 0.09
H = 19.95 +/- 0.10
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. The source position is
RA,Dec(J2000)=21:29:38.549,+37:07:58.79 with an uncertainty of 0.5 arcsec.
Our position is consistent with the candidate reported from Guidorzi,
et al. (GCN 19808).
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
Further observations are on-going.
GCN Circular 19808
Subject
GRB 160816A: LCOGT-FTN optical candidate
Date
2016-08-17T08:17:39Z (9 years ago)
From
Cristiano Guidorzi at Ferrara U,Italy <guidorzi@fe.infn.it>
C. Guidorzi (U. Ferrara), S. Kobayashi, I.A. Steele (LJMU), C.G. Mundell
(U. Bath), A. Gomboc (U. Nova Gorica) on behalf of a large collaboration
report:
The 2-m LCOGT Faulkes Telescope North began observing Fermi-LAT GRB
160816A (Racusin et al., GCN 19802) on August 17, 07:23:08 UT (13.9
hours after the burst trigger). Inside the Swift-XRT error circle of the
X-ray afterglow candidate (Kennea et al., GCN 19806) we find an
uncatalogued source at the following position:
RA(J2000)= 21:29:38.58
Dec(J2000)= +37:07:58.7
with an uncertainty of 1.0 arcsec and r~21.0 +- 0.2 mag (AB).
GCN Circular 19806
Subject
GRB 160816A: Swift-XRT afterglow detection
Date
2016-08-17T07:10:35Z (9 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU), D.N. Burrows (PSU),
S.L. Gibson (U. Leicester), J.P. Osborne (U. Leicester), K.L. Page (U.
Leicester), A. D'Ai (INAF-IASFPA), A. Maselli (INAF-IASFPA), A.
Melandri (INAF-OAB) and P.A. Evans (U. Leicester) report on behalf of
the Swift-XRT team:
Swift-XRT has performed follow-up observations of the
Fermi/LAT-detected burst GRB 160816A (Racusin et al. GCN Circ. 19802),
collecting 1.6 ks of Photon Counting (PC) mode data between T0+25.2 ks
and T0+31.8 ks.
An uncatalogued X-ray source is detected and is above the RASS limit,
and is therefore likely the GRB afterglow. The position of this source
is RA, Dec=322.4108, +37.1324 which is equivalent to:
RA (J2000): 21:29:38.59
Dec(J2000): +37:07:56.6
with an uncertainty of 3.8 arcsec (radius, 90% confidence). This
position is 3.8 arcmin from the Fermi/LAT position. The light curve is
consistent with a constant source of mean count rate 7.8e-02 ct/sec. A
power-law fit gives an index of 1.5 (+1.8, -1.7).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.7 (+0.6, -0.3). The
best-fitting absorption column is 2.97 (+3.55, -0.16) x 10^21 cm^-2,
consistent with the Galactic value of 2.8 x 10^21 cm^-2 (Willingale et
al. 2013). The counts to observed (unabsorbed) 0.3-10 keV flux
conversion factor deduced from this spectrum is 4.5 x 10^-11 (5.8 x
10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 2.97 (+3.55, -0.16) x 10^21 cm^-2
Galactic foreground: 2.8 x 10^21 cm^-2
Excess significance: <1.6 sigma
Photon index: 1.7 (+0.6, -0.3)
The results of the XRT-team automatic analysis of the likely afterglow
are at http://www.swift.ac.uk/ToO_GRBs/00020685/index_1.php.
The results of the full analysis of the XRT observations are available
at http://www.swift.ac.uk/ToO_GRBs/00020685.
This circular is an official product of the Swift-XRT team.
GCN Circular 19805
Subject
GRB 160816A: MASTER inspection
Date
2016-08-17T05:44:51Z (9 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, N.Tyurina, V.Kornilov,
P.Balanutsa, A.Kuznetsov, D.Kuvshinov
Lomonosov Moscow State University, Sternberg Astronomical Institute
R. Rebolo, M. Serra, N. Lodieu, G. Israelian
The Instituto de Astrofisica de Canarias
K.Ivanov, O.Gres, N.M.Budnev, S.Yazev,
Irkutsk State University
D.Buckley, S. Potter, A.Kniazev, M.Kotze
South African Astronomical Observatory
A. Tlatov, V.Senik, D. Dormidontov, A.Parkhomenko
Kislovodsk Solar Station of the Pulkovo Observatory
V.Yurkov, Yu.Sergienko, A.Gabovich
Blagoveschensk Educational State University, Blagoveschensk
Hugo Levato, Carlos Saffe
Instituto de Ciencias Astronomicas, de la Tierra y del Espacio (ICATE)
R.Podesta, C.Mallamaci, C.Lopez, F. Podesta
Observatorio Astronomico Felix Aguilar (OAFA)
MASTER-IAC robotic telescope (MASTER-Net: http://observ.pereplet.ru)
located in Teide observatory was pointed to the Fermi LAT
GRB160816A 924 sec after notice time at 2016-08-16 22:57:12 UT
(NOTICE_DATE:Tue 16 Aug 16 22:42:36 UT) and 19665 sec after the trigger
time(the delay in 15min was from the inspection of previous FermiGBM
alert and late notice time).
On our first 180s exposures we haven`t found optical transient within
LAT error-box (RA, Dec = 322.45, 37.16 (J2000) r=0.13).
There is a disc galaxy (unknown in NED) inside LAT error-box at the
position 21h 29m 23.16s +37d 05m 54.9s - possible host galaxy for GRB.
The 5-sigma upper limit has been about 19.7 mag
The message may be cited.
GCN Circular 19803
Subject
GRB 160816A: Swift ToO observations
Date
2016-08-17T00:35:15Z (9 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
P. A. Evans (U. Leicester) reports on behalf of the Swift team:
Swift has initiated a ToO observation of the Fermi/LAT GRB 160816A.
Automated analysis of the XRT data will be presented online at
http://www.swift.ac.uk/ToO_GRBs/00020685
Any uncatalogued X-ray sources detected in this analysis will be
reported on this website and via GCN COUNTERPART notices. These are
not necessarily related to the Fermi/LAT event. Any X-ray source
considered to be a probable afterglow candidate will be reported via a
GCN Circular after manual consideration.
Details of the XRT automated analysis methods are detailed in Evans et
al. (2007, A&A, 469, 379; 2009, MNRAS, 397, 1177 and 2014, ApJS, 210, 8).
This circular is an official product of the Swift-XRT team.
GCN Circular 19802
Subject
GRB 160816A: Fermi-LAT detection
Date
2016-08-16T23:15:28Z (9 years ago)
From
Judith Racusin at GSFC <judith.racusin@nasa.gov>
J. L. Racusin (NASA/GSFC), F. Dirirsa (U. Johannesburg), F. Longo (University and INFN, Trieste),
J. McEnery (NASA/GSFC), and G. Vianello (Stanford) report on behalf of the Fermi-LAT team:
At 17:30:58 on August 16, 2016 Fermi-LAT detected high-energy emission from GRB 160816A, which
was also detected by Fermi-GBM (trigger 493061460 / 160816730).
The best LAT on-ground location is found to be:
RA, Dec = 322.45, 37.16 (J2000)
with an error radius of 0.13 deg (90% containment, statistical error only).
This was 35 deg from the LAT boresight at the time of the trigger and triggered an autonomous repoint
of the spacecraft.
The data from the Fermi-LAT show a significant increase in the event rate that is spatially
and temporally correlated with the trigger with high significance. The highest-energy photon is a 9.5 GeV
event which is observed ~1100 seconds after the GBM trigger.
A Swift ToO request has been approved for this burst.
The Fermi-LAT point of contact for this burst is Francesco Longo (francesco.longo@trieste.infn.it).
The Fermi-LAT is a pair conversion telescope designed to cover the energy band from 20 MeV to greater
than 300 GeV. It is the product of an international collaboration between NASA and DOE in the U.S. and
many scientific institutions across France, Italy, Japan and Sweden.