GRB 180111A
GCN Circular 22318
Subject
GRB 180111A: Swift detection of a burst with an optical counterpart
Date
2018-01-11T17:12:29Z (7 years ago)
From
David Palmer at LANL <palmer@lanl.gov>
A. Y. Lien (GSFC/UMBC), A. P. Beardmore (U Leicester),
A. D'Ai (INAF-IASFPA), V. D'Elia (ASDC), A. Deich (PSU),
S. W. K Emery (UCL-MSSL), J.D. Gropp (PSU), J. A. Kennea (PSU),
N. P. M. Kuin (UCL-MSSL), K. L. Page (U Leicester),
D. M. Palmer (LANL), M. H. Siegel (PSU), A. Tohuvavohu (PSU) and
T. N. Ukwatta (LANL) report on behalf of the Neil Gehrels Swift
Observatory Team:
At 16:42:06 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 180111A (trigger=804692). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 149.841, +48.265 which is
RA(J2000) = 09h 59m 22s
Dec(J2000) = +48d 15' 53"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a complex
structure with a duration of about 80 sec. The peak count rate
was ~11000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 16:43:34.1 UT, 87.8 seconds after
the BAT trigger. Using promptly downlinked data we find a bright,
fading, uncatalogued X-ray source located at RA, Dec 149.77814,
48.26769 which is equivalent to:
RA(J2000) = 09h 59m 06.75s
Dec(J2000) = +48d 16' 03.7"
with an uncertainty of 3.7 arcseconds (radius, 90% containment). This
location is 150 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 in excess of the Galactic value (1.08 x
10^20 cm^-2, Willingale et al. 2013), with an excess column of 5.7
(+3.91/-3.29) x 10^21 cm^-2 (90% confidence).
The initial flux in the 2.5 s image was 5.71e-10 erg cm^-2 s^-1 (0.2-10
keV).
UVOT took a finding chart exposure of 150 seconds with the White
filter starting 97 seconds after the BAT trigger. An afterglow
candidate has been found in the initial data products at RA=9:59:7.0
Dec=+48:16:03.3 which is RA=149.77938, Dec=48.26758 deg (J2000)
matching the XRT position. This source lies in the wings of a bright
star and we will provide a magnitude after further ground processing.
Burst Advocate for this burst is A. Y. Lien (amy.y.lien AT nasa.gov).
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 22319
Subject
GRB 180111A: Enhanced Swift-XRT position
Date
2018-01-11T20:37:43Z (7 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 461 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 180111A, 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 = 149.77977, +48.26769 which is equivalent
to:
RA (J2000): 09h 59m 7.14s
Dec (J2000): +48d 16' 03.7"
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 22320
Subject
GRB180111A: Xinglong TNT possible optical detection
Date
2018-01-11T23:20:38Z (7 years ago)
From
L.P. Xin at NAOC <xlp@nao.cas.cn>
L. P. Xin, C. Liu, J. Y. Wei, Y. L. Qiu, J. S. Deng,
J. Wang, X. H. Han, X. M. Meng and C. Wu report:
We began to observe GRB 180111A (Lien et a l., GCN22318)
with Xinglong 0.8-m TNT telescope at 2018-01-11, 14:43:34(UT),
about 93 sec the burst.
We obtained several white and R-band images.
In any single white band frame, no any new optical transient
was detected within UVOT circle and XRT circle
(Lien et a l., GCN22318, Evens et al., GCN 22319)
down to 18.5 magnitude at the mid time of 113 sec after the burst .
However, there is a marginal source in the 20*20sec coadded image
within the XRT circle (Evens et al., GCN 22319), whose position is consistent
with the location of the reported optical counterpart (Lien et a l., GCN22318).
The brightness is about 20.0+/-0.3 calibrated by the local USNO B1.0 R2 mag
at the mid time of 300 sec after the burst.
We are making further analysis for the possible low S/N detection
since there is a bright star near the GRB location.
The message may be cited.
[GCN OPS NOTE(11jan18): The latter 'A' was added to the GRB name
in the Subject-line.]
GCN Circular 22321
Subject
GRB 180111A: AGILE/MCAL detection
Date
2018-01-12T00:02:25Z (7 years ago)
From
Francesco Verrecchia at ASDC <francesco.verrecchia@ssdc.asi.it>
F. Verrecchia (SSDC and INAF/OAR), A. Trois (INAF/OA-Cagliari), A.Ursi
(INAF/IAPS), M. Tavani (INAF/IAPS, and Univ. Roma Tor Vergata),
N. Parmiggiani (INAF/IASF-Bo), C. Pittori (SSDC and INAF/OAR), M. Marisaldi
(INAF/IASF-Bo and Bergen University), F. Longo (Univ. Trieste and INFN
Trieste), A. Bulgarelli (INAF/IASF-Bo), M. Cardillo (INAF/IAPS), F. Lucarelli
(SSDC and INAF/OAR), M. Pilia (INAF/OA-Cagliari), G. Piano (INAF/IAPS),
I. Donnarumma (ASI), G. Minervini, A. Argan, Y. Evangelista (INAF/IAPS),
V. Fioretti, F. Fuschino (INAF/IASF-Bo), A. Giuliani (INAF/IASF-Mi),
report on behalf of the AGILE Team:
The AGILE Mini-CALorimeter (MCAL) detected at T0 = 2018-01-11 16:42:06.0
+/- 0.02 UTC the long GRB 180111A reported by Swift (Lien et al., GCN 22318),
in the acquired data interval (following an internal trigger) started at
T1=16:42:05.50 UTC and ended at 16:42:12.40 UTC.
The MCAL light curve shows three main peaks starting at T0-0.15 s till ~6 s,
with the main part within T0-0.10 s and T0+5.40 s. The main GRB interval
released a total number of ~5537 counts at E>400 keV in the detector, above
an average background rate of 18 counts/32ms.
The AGILE-MCAL detector has a full solid angle acceptance, and is operational
in the range 0.4 - 100 MeV.
GCN Circular 22322
Subject
GRB 180111A: Swift-XRT refined Analysis
Date
2018-01-12T01:25:41Z (7 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
S. J. LaPorte (PSU), J.A. Kennea (PSU), B. Sbarufatti (INAF-OAB/PSU),
A.P. Beardmore (U. Leicester), P.A. Evans (U. Leicester), S.L. Gibson
(U. Leicester), P. D'Avanzo (INAF-OAB), V. D'Elia (ASDC), A. D'Ai
(INAF-IASFPA) and A.Y. Lien report on behalf of the Swift-XRT team:
We have analysed 6.1 ks of XRT data for GRB 180111A (Lien et al. GCN
Circ. 22318), from 94 s to 23.6 ks after the BAT trigger. The data
comprise 117 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. 22319).
The late-time light curve (from T0+4.0 ks) can be modelled with a
power-law decay with a decay index of alpha=1.46 (+0.38, -0.29).
A spectrum formed from the WT mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.48 (+/-0.09). The
best-fitting absorption column is 4.0 (+3.0, -2.6) x 10^20 cm^-2, in
excess of the Galactic value of 1.1 x 10^20 cm^-2 (Willingale et al.
2013). The PC mode spectrum has a photon index of 1.66 (+0.21, -0.12)
and a best-fitting absorption column of 1.17 (+4.88, -0.09) x 10^20
cm^-2. The counts to observed (unabsorbed) 0.3-10 keV flux conversion
factor deduced from this spectrum is 3.8 x 10^-11 (3.9 x 10^-11) erg
cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 1.17 (+4.88, -0.09) x 10^20 cm^-2
Galactic foreground: 1.1 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index: 1.66 (+0.21, -0.12)
If the light curve continues to decay with a power-law decay index of
1.46, the count rate at T+24 hours will be 9.2 x 10^-4 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 3.5 x
10^-14 (3.6 x 10^-14) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00804692.
This circular is an official product of the Swift-XRT team.
GCN Circular 22323
Subject
GRB 180111A: RATIR Optical and NIR Observations
Date
2018-01-12T15:36:30Z (7 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), Ori Fox (STScI), J. Xavier
Prochaska (UCSC), Josh Bloom (UCB), Antonino Cucchiara (UVI), Eleonora
Troja (GSFC), Owen Littlejohns (ASU), Enrico Ramirez-Ruiz (UCSC), Jes��s
Gonz��lez (UNAM), Carlos Rom��n-Z����iga (UNAM), Harvey Moseley (GSFC), John
Capone (UMD), V. Zach Golkhou (U. Wash.), and Vicki Toy (UMD) report:
We observed the field of GRB 180111A (Lien, et al., GCN 22318) 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 2018/01 12.21 to 2018/01 12.56 UTC (12.35 to
20.68 hours after the BAT trigger), obtaining a total of 5.31 hours
exposure in the r and i bands and 2.22 hours exposure in the Z and Y bands.
We find a source within the Swift-XRT error circle (Evans, et al., 22319).
In comparison with the SDSS DR9 and 2MASS catalogs, we measure:
r = 20.90 +/- 0.10
i = 20.41 +/- 0.10
Z = 20.61 +/- 0.15
Y = 20.41 +/- 0.15
These magnitudes are in the AB system and are not corrected for Galactic
extinction in the direction of the GRB. We note that there is an r=22.7
mag SDSS source, perhaps the host galaxy, within the XRT error region and
at a position consistent with our source position.
We thank the staff of the Observatorio Astron��mico Nacional in San Pedro
M��rtir.
GCN Circular 22324
Subject
GRB 180111A: Swift-BAT refined analysis
Date
2018-01-12T16:04:27Z (7 years ago)
From
Amy Lien at GSFC <amy.y.lien@nasa.gov>
M. Stamatikos (OSU), S. D. Barthelmy (GSFC),
J. R. Cummings (CPI), H. A. Krimm (NSF/USRA),
A. Y. Lien (GSFC/UMBC), C. B. Markwardt (GSFC),
D. M. Palmer (LANL), T. Sakamoto (AGU),
T. N. Ukwatta (LANL) (i.e. the Swift-BAT team):
Using the data set from T-240 to T+962 sec from the recent telemetry downlink,
we report further analysis of BAT GRB 180111A (trigger #804692)
(Lien et al., GCN Circ. 22318). The BAT ground-calculated position is
RA, Dec = 149.782, 48.254 deg which is
RA(J2000) = 09h 59m 07.7s
Dec(J2000) = +48d 15' 14.6"
with an uncertainty of 1.0 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 70%.
The mask-weighted light curve shows several overlapping pulses that starts
at ~ T0 and ends at ~ T+70 s. The main peak occurs at ~ T+ 14 s.
T90 (15-350 keV) is 50.6 +- 1.9 sec (estimated error including systematics).
The time-averaged spectrum from T-0.30 to T+68.59 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
1.30 +- 0.03. The fluence in the 15-150 keV band is 1.02 +- 0.02 x 10^-5 erg/cm2.
The 1-sec peak photon flux measured from T+13.89 sec in the 15-150 keV band
is 4.9 +- 0.3 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/804692/BA/
GCN Circular 22327
Subject
GRB 180111A: Swift/UVOT Detection
Date
2018-01-13T13:53:26Z (7 years ago)
From
Jeffrey Gropp at PSU <jdg44@psu.edu>
J. D. Gropp (PSU) and A. Y. Lien (GSFC/UMBC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 180111A
98 s after the BAT trigger (Lien et al., GCN Circ. 22318).
A fading source consistent with the XRT position
(Evans et al. GCN Circ. 22319)
is detected in the initial UVOT exposures.
Preliminary detections 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 84 233 147 19.95+-0.21
white 86 6202 552 20.37+-0.16
v 64 5181 206 >19.23
b 4365 6002 393 >20.60
u 296 5795 639 20.25+-0.35
w1 5391 5591 196 >19.50
m2 650 670 19 >17.15
w2 4776 6407 393 19.60+-0.27
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 22331
Subject
GRB 180111A: AbAO optical observations
Date
2018-01-13T19:36:34Z (7 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
E. Mazaeva (IKI), A. Pozanenko (IKI), R. Inasaridze (AbAO), S. Schmalz
(ISON), V. Ayvazian (AbAO), O. Kvaratskhelia (AbAO), G. Inasaridze
(AbAO), A. Volnova (IKI), I. Molotov (KIAM), report on behalf of larger
GRB follow-up collaboration:
We observed the field of the Swift GRB 180111A (Lien et al., GCN 22318)
with AS-32 (0.7m) telescope of Abastumani Observatory starting on Jan., 11
(UT) 23:53:51. We obtained several unfiltered images of the field. Within
enhanced XRT error circle (Evans et al., GCN 22319) we detected the
afterglow (Lien et al., GCN 22318; Xin et al., 22320; GCN Butler et al.,
GCN 22323; Gropp et al., GCN 22327).
Preliminary photometry of the afterglow is following
Date UT start t-T0 Filter Exp. OT Err UpLim
(3 sigma)
(mid, days) (s)
2018-01-11 23:53:51 0.3213 CR 62*60 20.7 0.2 22.0
Photometry is based on nearby USNO-B1.0 stars (R2 magnitudes)
USNO-B.1_id R2
1382-0239231 15.78
1383-0226386 16.52
1383-0226440 15.90
GCN Circular 22333
Subject
GRB 180111A CALET Gamma-Ray Burst Monitor detection
Date
2018-01-14T12:55:13Z (7 years ago)
From
Takanori Sakamoto at AGU <tsakamoto@phys.aoyama.ac.jp>
Y. Asaoka (Waseda U), A. Yoshida, T. Sakamoto, V. Pal'shin, Y. Kawakubo,
M. Moriyama, Y. Yamada, A. Tezuka, S. Matsukawa (AGU), K. Yamaoka (Nagoya U),
S. Nakahira (RIKEN), I. Takahashi (IPMU), S. Ozawa, S. Torii (Waseda U),
Y. Shimizu, T. Tamura (Kanagawa U), W. Ishizaki (ICRR), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), A. V. Penacchioni, P. S. Marrocchesi (U of Siena)
and the CALET collaboration:
The long-duration GRB 180111A (Lien et al., GCN circ. 22318; Verrecchia
et al., GCN circ. 22321) triggered the CALET Gamma-ray Burst Monitor (CGBM)
at 16:42:04.15 on 11 January 2018. The burst signal was seen by the all CGBM
instruments.
The light curve of the SGM shows two overlapping peaks. The emission
starts at T+2.1 sec, peaks at T+2.6 sec and ends at T+43.4 sec. The T90 and
the T50 durations measured by the SGM data are 34.3 +- 6.6 sec and
11.0 +- 2.4 sec (40-1000 keV), respectively.
The ground processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1199723921
The CALET data used in this analysis are provided by the Waseda CALET Operation
Center located at the Waseda University.
GCN Circular 22336
Subject
Konus-Wind observation of GRB 180111A
Date
2018-01-15T10:37:21Z (7 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 bright long-duration GRB 180111A
(Swift-BAT detection: Lien et al., GCN Circ. 22318;
AGILE-MCAL detection: Verrecchia et al., GCN Circ. 22321)
triggered Konus-Wind at T0=60130.616 s UT (16:42:10.616).
The burst light curve shows a multipeaked structure
which starts at ~T0-0.2 s and has a total duration of ~61 s.
The emission is seen up to ~6 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB180111_T60130/
As observed by Konus-Wind, the burst
had a fluence of 8.44(-0.57,+0.64)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+0.018 s,
of 1.06(-0.21,+0.22)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+39.424 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.94(-0.06,+0.06)
and Ep = 894(-95,+113) keV (chi2 = 106/98 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.7
(chi2 = 106/97 dof).
The spectrum near the maximum count rate
(measured from T0+0.000 to T0+7.424 s)
is best fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model:
with alpha = -0.51(-0.08,+0.09)
and Ep = 895(-82,+94) keV (chi2 = 89/98 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.8
(chi2 = 89/97 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
GCN Circular 22341
Subject
GRB 180111A: Insight-HXMT/HE observation
Date
2018-01-15T12:20:59Z (7 years ago)
From
Shaolin Xiong at IHEP <xiongsl@ihep.ac.cn>
G. Li, S. L. Xiong, X. B. Li, C. K. Li, J. Y. Liao, C. Z. Liu, X. F. Li,
Z. W. Li, X. F. Lu, Z. Chang, J. L. Zhao, A. M. Zhang, C. L. Zou (IHEP),
Y. J. Jin, Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song, H.
Y. Wang, M. Wu, Y. P. Xu, S. N. Zhang (IHEP), report on behalf of the
Insight-HXMT team:
At 2018-01-11T16:42:06 (T0), Insight-HXMT/HE detected
GRB 180111A (trigger ID: HEB180111695) in a routine search of the
data,which is also triggered by Swift/BAT (Lien et al.,GCN
22318),AGILE/MCAL(Verrecchia et al.,GCN 22321),and CALET(Asaoka et
al.,GCN 22333).
The Insight-HXMT/HE light curve mainly consists of
multi-pulses with a duration (T90) of 19.94 s measured from T0+0.185 s.
The 500-ms peak rate, measured from T0+0.422 s, is 2332.29 cnts/sec.
The total counts from this burst is 13972.02 counts. URL_LC:
http://www.hxmt.org/images/GRB/HEB180111695_lc.jpg
All measurements above are made with the CsI detectors operating in the GRB mode, in
which the energy range is increased to about 200 - 3000 keV (record
energy), compared to the normal mode of 80 - 800 keV. Only gamma-rays
with energy greater than about 200 keV can penetrate the spacecraft and
leave signals in the CsI detectors installed inside of the telescope.
The analysis results presented above are preliminary; final results will
be published elsewhere. Insight-HXMT is the first Chinese space X-ray
telescope, which was funded jointly by the China National Space
Administration (CNSA) and the Chinese Academy of Sciences (CAS). More
information about it could be found at:
http://www.hxmt.org/index.php/enhome .
GCN Circular 22352
Subject
GRB 180111A AROMA-N optical observation
Date
2018-01-16T14:15:09Z (7 years ago)
From
Takanori Sakamoto at AGU <tsakamoto@phys.aoyama.ac.jp>
Y. Kitaoka, T. Sakamoto (AGU)
We observed the field of GRB 180111A detected by Swift
(Lien et al. GCN circ. 22318) with the 0.3 m AROMA-N telescope
located at Aoyama Gakuin University (Sagamihara, Japan).
10 images of 60 sec exposures were taken in the R filter starting
from January 11 on 16:44:50 (UT) about 3 minutes after the trigger
and stopped on 16:56:51 (UT). We do not detect the optical afterglow
both in the individual images and the stacked image at the location of
the optical afterglow (Lien et al. GCN circ. 22318). The estimated
five sigma upper limit is ~16.6 mag using the USNO-B1 catalog.