GRB 200711A
GCN Circular 28094
Subject
GRB 200711A: Insight-HXMT/HE detection
Date
2020-07-14T09:52:44Z (5 years ago)
From
Shuo Xiao at IHEP <xiaoshuo@ihep.ac.cn>
S. Xiao, C. Cai, Y. F. Du, Y. G. Zheng, Q. Luo, Q. B. Yi,
Y. Huang, C. K. Li, G. Li, X. B. Li, J. Y. Liao, S. L. Xiong,
C. Z. Liu, X. F. Li, Z. W. Li, Z. Chang, A. M. Zhang,
Y. F. Zhang, X. F. Lu, C. L. Zou (IHEP), Y. J. Jin,
Z. Zhang (THU), T. P. Li (IHEP/THU), F. J. Lu, L. M. Song,
M. Wu, Y. P. Xu, S. N. Zhang (IHEP),
report on behalf of the Insight-HXMT team:
At 2020-07-11T11:04:32.93 (T0), Insight-HXMT/HE detected
GRB 200711A (trigger ID: HEB200711461) in a routine search of the data,
which also triggered Fermi-GBM (Poolakkil et al. GCN 28080)
and Swift-BAT (Marshall et al. GCN 28078).
The Insight-HXMT/HE light curve mainly consists of single
pulse with a duration (T90) of 9.15 s measured from T0-0.64 s.
The 1-ms peak rate, measured from T0+3.56 s, is 1098 cnts/sec.
The total counts from this burst is 3109 counts.
URL_LC: http://twiki.ihep.ac.cn/pub/HXMT/GRBList/HEB200711461_lc.jpg
All measurements above are made with the CsI detectors operating in the
regular mode with the energy range of about 80-800 keV (deposited energy).
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.
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.
GCN Circular 28087
Subject
GRB 200711A: CALET Gamma-Ray Burst Monitor detection
Date
2020-07-13T12:00:51Z (5 years ago)
From
Valentin Pal'shin at AGU <val@phys.aoyama.ac.jp>
Y. Asaoka (Waseda U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
S. Torii (Waseda U), Y. Shimizu, T. Tamura (Kanagawa U),
N. Cannady (GSFC/UMBC), M. L. Cherry (LSU),
S. Ricciarini (U of Florence), P. S. Marrocchesi (U of Siena),
and the CALET collaboration:
The long GRB 200711A (Swift detection: Marshall et al., GCN Circ. 28078;
Fermi GBM detection: Poolakkil et al., GCN Circ. 28080;
Fermi-LAT detection: Crnogorcevic et al., GCN Circ. 28083;
https://gcn.gsfc.nasa.gov/other/200711A.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM)
at 11:04:34.187 UTC on 11 July 2020
(http://cgbm.calet.jp/cgbm_trigger/flight/1278500601/).
The burst signal was seen only by the SGM detector.
The burst light curve shows a weak pulse which starts at T-0.9 sec and
ends at T+4.0 sec. The T90 and T50 durations measured by the SGM data are
4.2 +- 1.3 sec and 2.1 +- 1.3 sec (40-1000 keV), respectively.
The ground processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1278500601/
The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.
GCN Circular 28086
Subject
GRB 200711A: AbAO optical upper limit
Date
2020-07-13T09:39:24Z (5 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
A. Pozanenko (IKI), N. Pankov (HSE), K. Kamyshnikov (HSE), R. Ya.
Inasaridze (AbAO), V.R. Ayvazian (AbAO), G. V. Kapanadze (AbAO), S.
Belkin (IKI), E. Mazaeva (IKI), A. Volnova (IKI), I. Molotov (KIAM)
report on behalf of GRB IKI FuN:
We observed the field of GRB 200711A (Fermi GBM Team, GCN 28077;
Marshall et al., GCN 28078; Crnogorcevic et al., GCN 28083) with AS-32
(0.7m) telescope of Abastumani Observatory starting on 2020-07-11 (UT)
23:05:40. We do not detect any object within the enhanced XRT position
error circle (Osborne et al., GCN 28081). Preliminary photometry of the
field is following.
Date UT start t-T0 Filter Exp. OT Err. UL
(mid, days) (s)
2020-07-11 23:05:40 0.50074 R 49*60 n/d n/d 21.3
The photometry is based on nearby USNO-B1.0 stars
GCN Circular 28085
Subject
GRB 200711A: Swift/UVOT Upper Limits
Date
2020-07-13T02:22:08Z (5 years ago)
From
Kira Simpson at PSU <kira.simpson1984@gmail.com>
GRB 200711A: Swift/UVOT Upper Limits
K. K. Simpson (PSU) and F. E. Marshall (NASA/GSFC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 200711A
170 s after the BAT trigger (Marshall et al., GCN Circ. 28078).
No optical afterglow consistent with the BAT position
(Marshall et al. GCN Circ 28078)
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 170 319 147 >20.2
white 170 999 310 >20.6
v 404 4651 255 >18.7
b 503 868 58 >19.1
u 477 5088 80 >19.0
w1 453 5061 255 >19.3
m2 428 448 19 >18.0
w2 379 4446 255 >19.5
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.96 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 28084
Subject
GRB 200711A: Swift-BAT refined analysis
Date
2020-07-12T19:14:05Z (5 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),
S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), F. E. Marshall (NASA/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 200711A
(trigger #981957) (Marshall et al., GCN Circ. 28078).
The BAT ground-calculated position is
RA, Dec = 285.975, -0.134 deg which is
RA(J2000) = 19h 03m 53.9s
Dec(J2000) = -00d 08' 04.1"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 8%.
The mask-weighted light curve shows a multi-peaked structure that
starts at ~T-5 s and ends at ~T+30 s. The three major peaks occur
at ~T0, ~T+5 s, and ~T+20 s, respectively. T90 (15-350 keV)
is 29.39 +- 3.07 sec (estimated error including systematics).
The time-averaged spectrum from T-4.72 to T+29.73 sec is best fit
by a simple power-law model. The power law index of the time-averaged
spectrum is 1.42 +- 0.10. The fluence in the 15-150 keV band
is 5.3 +- 0.3 x 10^-6 erg/cm2. The 1-sec peak photon flux measured
from T+0.20 sec in the 15-150 keV band is 7.7 +- 1.0 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/981957/BA/
GCN Circular 28083
Subject
GRB 200711A: Fermi-LAT marginal detection
Date
2020-07-12T18:47:27Z (5 years ago)
From
Milena Crnogorcevic at GSFC,UMD, Fermi <milena.crnogorcevic@nasa.gov>
M. Crnogorcevic (Univ. of Maryland & NASA/GSFC), M. Kovacevic (INFN Perugia),
M. Ohno (Hiroshima Univ.), F. Longo (University & INFN Trieste),
report on behalf of the Fermi-LAT Collaboration:
On July, 11th, 2020, Fermi-LAT detected high-energy emission from GRB 200711A,
which was also detected by Fermi-GBM (trigger 616158277/200711461;
Poolakkil et al. GCN 28080) and Swift-BAT (Marshall et al. GCN 28078).
The best LAT on-ground location is found to be RA, Dec = 285.8, 0.2 (degrees, J2000)
with an error radius of 0.4 deg (90% containment, statistical error only).
The 95% containment error is consistent with the Swift-XRT position
(Osborne et al. GCN 28081).
This GRB was outside LAT FoV at the trigger time of the GBM and came
into the LAT FoV around 200 s after the trigger. The data from the
Fermi-LAT in the time interval 200-600 s after the GBM trigger at the
Swift-XRT position show a marginal increase of the detection
significance of the high energy (GeV) photons for this burst.
The photon flux above 100 MeV in the time interval 200 - 600 s after
the GBM trigger is 3.3e-6 +/- 1.9e-6 ph/cm2/s.
The highest-energy photon is a 5.7 GeV event which is observed 542 seconds
after the GBM trigger.
The Fermi-LAT point of contact for this burst is
Milena Crnogorcevic (mcrnogor@astro.umd.edu).
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.
GCN Circular 28082
Subject
GRB 200711A: KAIT Optical Upper Limit
Date
2020-07-12T07:57:23Z (5 years ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
WeiKang Zheng and Alexei V. Filippenko (UC Berkeley) report on
behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, responded to GRB 200711A (GBM detection:
GCN 28077; Swfit detection: Marshall et al., GCN 28078)
starting at ~0.90 hours after the Swfit trigger, and again
on the second night around 0.81 days after burst. Observations
were performed in the clear (roughly R) filters, and the exposure
time was 20 s per image. We do not detect any optical afterglow
candidate within the enhanced XRT position error circle (Osborne
et al., GCN 28081), neither in the first night image with upper
limit of ~17.5 mag calibrated to the Pan-STARRS1 catalog, nor in
the second night co-added image with upper limit of ~20.0 mag.
GCN Circular 28081
Subject
GRB 200711A: Swift-XRT refined Analysis
Date
2020-07-12T06:34:40Z (5 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
J.P. Osborne (U. Leicester), M. Capalbi (INAF-IASFPA), M. Perri (ASDC),
V. D'Elia (ASDC), J.A. Kennea (PSU), A. Tohuvavohu (U. Toronto), B.
Sbarufatti (PSU), K.L. Page (U. Leicester), A.P. Beardmore (U.
Leicester) and F.E. Marshall report on behalf of the Swift-XRT team:
We have analysed 6.9 ks of XRT data for GRB 200711A (Marshall et al.
GCN Circ. 28078), from 150 s to 40.4 ks after the BAT trigger. The
data comprise 29 s in Windowed Timing (WT) mode (the first 10 s were
taken while Swift was slewing) with the remainder in Photon Counting
(PC) mode. Using 1145 s of PC mode data and 2 UVOT images, we find an
enhanced XRT position (using the XRT-UVOT alignment and matching UVOT
field sources to the USNO-B1 catalogue): RA, Dec = 285.97020, -0.14708
which is equivalent to:
RA (J2000): 19h 03m 52.85s
Dec(J2000): -00d 08' 49.5"
with an uncertainty of 1.6 arcsec (radius, 90% confidence).
The light curve can be modelled with an initial power-law decay with an
index of alpha=0.51 (+0.13, -0.14), followed by a break at T+3349 s to
an alpha of 1.41 (+/-0.09).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 2.01 (+0.22, -0.21). The
best-fitting absorption column is 1.65 (+0.30, -0.27) x 10^22 cm^-2,
in excess of the Galactic value of 5.7 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 5.6 x 10^-11 (1.2 x 10^-10) erg
cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 1.65 (+0.30, -0.27) x 10^22 cm^-2
Galactic foreground: 5.7 x 10^21 cm^-2
Excess significance: 6.5 sigma
Photon index: 2.01 (+0.22, -0.21)
If the light curve continues to decay with a power-law decay index of
1.41, the count rate at T+24 hours will be 9.6 x 10^-3 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 5.4 x
10^-13 (1.1 x 10^-12) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00981957.
This circular is an official product of the Swift-XRT team.
GCN Circular 28080
Subject
GRB 200711A: Fermi GBM detection
Date
2020-07-11T18:47:25Z (5 years ago)
From
Suraj Poolakkil at UAH <sp0076@uah.edu>
S.Poolakkil (UAH), E. Bissaldi (Politecnico and INFN Bari) and C. Meegan
(UAH)
report on behalf of the Fermi GBM Team:
"At 11:04:32.93 UT on 11 July 2020, the Fermi Gamma-Ray Burst Monitor
triggered and located GRB 200711A(trigger 616158277 / 200711461),
which was also detected by the Swift/BAT (Marshall et al. 2020, GCN 28078).
The GBM on-ground location is consistent with the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 77
degrees.
The GBM light curve consists of a single bright pulse followed by some
extended emission with a duration (T90) of about 29 s (50-300 keV).
The time-averaged spectrum from T0 s to T0+24.58 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -1.04 +/- 0.03 and
the cutoff energy, parameterized as Epeak, is 287 +/- 18 keV.
A Band function fits equally well, with Epeak = 215 +/- 23 keV,
alpha = -0.95 +/- 0.05 and beta = -2.04 +/- 0.10.
The event fluence (10-1000 keV) in this time interval is
(1.510 +/- 0.042)E-05 erg/cm^2. The 1-sec peak photon flux
measured starting from T0+3.64 s in the 10-1000 keV band
is 16.3 +/- 0.3 ph/s/cm^2.
The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html
For Fermi GBM data and info, please visit the official Fermi GBM Support
Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"
GCN Circular 28079
Subject
Swift GRB 200711A: Global MASTER-Net observations report
Date
2020-07-11T18:41:12Z (5 years ago)
From
Vladimir Lipunov at Moscow State U/Krylov Obs <lipunov@xray.sai.msu.ru>
V. Lipunov, E. Gorbovskoy, V.Kornilov, N.Tyurina, P.Balanutsa, A.Kuznetsov, F.Balakin,
V.Vladimirov, D. Vlasenko, I.Gorbunov, D.Zimnukhov, V.Senik, T.Pogrosheva,
D.Kuvshinov, D. Cheryasov
(Lomonosov Moscow State University, SAI, Physics Department),
R. Podesta, C.Lopez, F. Podesta, C.Francile
(Observatorio Astronomico Felix Aguilar OAFA),
H.Levato
(Instituto de Ciencias Astronomicas, de la Tierra y del Espacio ICATE),
R. Rebolo, M. Serra
(The Instituto de Astrofisica de Canarias),
D. Buckley
(South African Astronomical Observatory),
O.A. Gres, N.M. Budnev, O.Ershova
(Irkutsk State University, API),
A. Tlatov, D. Dormidontov
(Kislovodsk Solar Station of the Pulkovo Observatory),
V. Yurkov, A. Gabovich, Yu. Sergienko
(Blagoveschensk Educational State University)
MASTER-Tavrida robotic telescope (Global MASTER-Net: http://observ.pereplet.ru, Lipunov et al., 2010, Advances in Astronomy, vol. 2010, 30L) located in Russia (Lomonosov MSU, SAI Crimea astronomical station) was pointed to the Swift GRB 200711A ( F. E. Marshall et al., GCN 28078) errorbox 26829 sec after notice time and 26854 sec after trigger time at 2020-07-11 18:32:11 UT, with upper limit up to 15.9 mag. Observations started at twilight. The observations began at zenith distance = 59 deg. The sun altitude is -10.2 deg.
MASTER-Kislovodsk robotic telescope located in Russia (Lomonosov MSU, Kislovodsk Solar Station of Pulkovo observatory) was pointed to the Swift GRB 200711A errorbox 26939 sec after notice time and 26964 sec after trigger time at 2020-07-11 18:34:00 UT, with upper limit up to 16.7 mag. Observations started at twilight. The observations began at zenith distance = 54 deg. The sun altitude is -15.0 deg.
The galactic latitude b = -3 deg., longitude l = 35 deg.
Real time updated cover map and OT discovered available here:
https://master.sai.msu.ru/site/master2/observ.php?id=1399126
We obtain a following upper limits.
Tmid-T0 | Site |Filt.| Expt. | Limit| Comment
_________|_____________________|_____|_______|______|________
26945 | MASTER-Tavrida | C | 180 | 15.9 |
26994 | MASTER-Kislovodsk | C | 60 | 16.7 |
Filter C is a clear (unfiltred) band.
The observation and reduction will continue.
The message may be cited.
GCN Circular 28078
Subject
GRB 200711A: Swift detection of a burst
Date
2020-07-11T11:29:06Z (5 years ago)
From
Scott Barthelmy at NASA/GSFC <scott@milkyway.gsfc.nasa.gov>
F. E. Marshall (NASA/GSFC), E. Ambrosi (INAF-IASFPA),
S. D. Barthelmy (GSFC), A. D'Ai (INAF-IASFPA), V. D'Elia (SSDC),
J.D. Gropp (PSU), N. J. Klingler (PSU), K. L. Page (U Leicester),
D. M. Palmer (LANL) and A. Tohuvavohu (U Toronto) report on behalf of
the Neil Gehrels Swift Observatory Team:
At 11:04:36 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 200711A (trigger=981957). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 285.977, -0.136, which is
RA(J2000) = 19h 03m 54s
Dec(J2000) = -00d 08' 09"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed multiple peaks
with a duration of about 30 sec. The peak count rate
was ~6000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 11:07:22.8 UT, 166.3 seconds after
the BAT trigger. Due to a poor slew, the promptly downlinked data only
cover 30% of the BAT error circle. No source was detected in 779 s within
the small part of the BAT error region covered. We are waiting for the
full dataset covering the full field of view to detect and localise
the XRT counterpart.
UVOT took a finding chart exposure of 150 seconds with the White
filter starting 169 seconds after the BAT trigger. This is a very crowded
region with large extinction. No credible afterglow candidate has been
found in the initial data products.
Burst Advocate for this burst is F. E. Marshall (marshall AT milkyway.gsfc.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/)
GCN Circular 28077
Subject
GRB 200711A: Fermi GBM Final Real-time Localization
Date
2020-07-11T11:14:53Z (5 years ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
The Fermi GBM team reports the detection of a likely LONG GRB
At 11:04:32 UT on 11 Jul 2020, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 200711A (trigger 616158277.930672 / 200711461).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 287.1, Dec = 1.3 (J2000 degrees, equivalent to J2000 19h 08m, 1d 18'), with a statistical uncertainty of 1.6 degrees.
The angle from the Fermi LAT boresight is 79.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200711461/quicklook/glg_skymap_all_bn200711461.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200711461/quicklook/glg_healpix_all_bn200711461.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2020/bn200711461/quicklook/glg_lc_medres34_bn200711461.gif