GRB 191031D
GCN Circular 26841
Subject
GRB 191031D: XMM-Newton upper limit
Date
2020-01-21T16:38:21Z (6 years ago)
From
Paolo D'Avanzo at INAF-OAB <pda.davanzo@gmail.com>
P. D'Avanzo, S. Campana, M. G. Bernardini (INAF-OAB), M. Branchesi (GSSI), E. Chassande-Mottin (APC, CNRS/IN2P3),
S. Covino (INAF-OAB), V. D'Elia (ASI-SSDC), G. Ghirlanda, G. Ghisellini, A. Melandri, L. Nava, O. S. Salafia (INAF-OAB),
R. Salvaterra (INAF-IASFMi), G. Tagliaferri (INAF-OAB), S. D. Vergani (GEPI/Obs. Paris) report:
XMM-Newton started observing the field of the short GRB 191031D (Fermi-GBM et al., GCN Circ. 26111; D'Elia et al., GCN Circ. 26112;
Mailyan et al., GCN Circ. 26118; Ursi et al., GCN Circ. 26123; Frederiks et al., GCN Circ. 26126; Gaikwad et al., GCN Circ. 26129;
Frederiks et al., GCN Circ. 26149; Shimizu et al., GCN Circular. 26240) on 14 November 2019 at 09:58:00 UT, ~ 13.5 d after the burst.
The last ~18 ks of the observation were affected by an enhanced background and were filtered out. The resulting EPIC/pn exposure
time is 27.2 ks.
No X-ray source is detected within the enhanced XRT position (Osborne et al., GCN Circ. 26117) down to a 3sigma limit of ~ 1.6e-3 cts/s
in the 0.3-10 keV energy range. Assuming the spectral parameters derived by Swift/XRT, the above value translates into an unabsorbed
flux limit of ~ 4.8e-15 erg/cm^2/s in the 0.3-10 keV energy range.
We acknowledge the XMM-Newton staff for their support in scheduling and executing these observations.
GCN Circular 26240
Subject
GRB 191031D: CALET Gamma-Ray Burst Monitor detection
Date
2019-11-13T03:39:09Z (6 years ago)
From
Valentin Pal'shin at AGU <val@phys.aoyama.ac.jp>
Y. Shimizu (Kanagawa U),
A. Yoshida, T. Sakamoto, V. Pal'shin, S. Sugita (AGU),
Y. Kawakubo (LSU), K. Yamaoka (Nagoya U), S. Nakahira (RIKEN),
Y. Asaoka, S. Torii (Waseda U), 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 short bright GRB 191031D (Swift detection: Ambrosi et al.,
GCN Circ. 26112, Sakamoto et al., GCN Circ. 26133;
Fermi GBM detection: Mailyan and Meegan, GCN Circ. 26118;
AGILE/MCAL observations: Ursi et al., GCN Circ. 26123;
Konus-Wind observation: Frederiks et al., GCN Circ. 26126, 26149;
AstroSat CZTI detection: Gaikwad et al., GCN Circ. 26129;
https://gcn.gsfc.nasa.gov/other/191031D.gcn3)
triggered the CALET Gamma-ray Burst Monitor (CGBM) at 21:23:31.261 UTC
on 31 October 2019. The burst signal was seen by all CGBM detectors.
No real-time CGBM GCN notice was distributed about this trigger because
the real-time communication from the ISS was off (loss of signal).
The burst light curve shows a multi-peak structure which starts at T-0.168
sec, peaks at 0.008 sec and ends at T+0.192 sec. The T90 and T50 durations
measured by the SGM data are 0.240 +- 0.079 sec and 0.104 +- 0.008 sec
(40-1000 keV), respectively.
The ground processed light curve is available at
http://cgbm.calet.jp/cgbm_trigger/ground/1256592147/
The CALET data used in this analysis are provided by
the Waseda CALET Operation Center located at the Waseda University.
GCN Circular 26175
Subject
GRB 191031D: Chandra upper limit
Date
2019-11-05T14:50:39Z (6 years ago)
From
Wen-fai Fong at Northwestern U <wfong@northwestern.edu>
A. Rouco Escorial, W. Fong, (Northwestern), E. Berger (Harvard), and R. Margutti (Northwestern) report:
"We initiated observations of the location of the short-duration GRB191031D (Fermi-GBM et al., GCN 26111; D'Elia et al., GCN 26112; Mailyan et al., GCN 26118) with the Chandra X-ray Observatory on 2019 Nov 3.694 UT (mid-time of 16:39:42 UT), 2.8 days post-burst under Program 20500021 (ObsID 21302; PI: Berger). The effective exposure time is 19.8 ksec.
We do not detect an X-ray source within the enhanced XRT position (Osborne et al., GCN 26117), and calculate a 3-sigma limit of <4.5e-4 cps in the 0.5-10 keV energy range using the method described by Gehrels (1986). Applying the best-fit XRT spectral parameters, we calculate an unabsorbed flux limit of <6.0e-15 erg/s/cm^2 in the 0.3-10 keV energy range.
Relative to the XRT light curve starting from t~900 sec post-burst, this constrains the late-time X-ray power-law decline to be alpha<-0.75 (where F~t^alpha).
We thank the Chandra staff for the rapid scheduling and execution of these observations."
GCN Circular 26150
Subject
GRB 191031D: Zwicky Transient Facility Follow-Up of a Swift Short GRB (Trigger 594249816/191031891)
Date
2019-11-03T19:13:26Z (6 years ago)
From
Tomas Ahumada at U. of Maryland <tahumada@astro.umd.edu>
Tom��s Ahumada (UMD), Shreya Anand (Caltech), Michael W. Coughlin (Caltech),
S. Bradley Cenko (NASA GSFC), Eric C. Bellm (UW), Leo P. Singer (NASA
GSFC), Mansi M. Kasliwal (Caltech) on behalf of the ZTF and GROWTH
collaborations
We observed the localization region of the short GRB 191031D (trigger
594249816/191031891) detected by the Swift XRT, BAT and the Gamma-Ray Burst
Monitor (GBM) on the Fermi satellite with the Palomar 48 inch telescope
equipped with the 47 square degree Zwicky Transient Facility (ZTF) camera.
These observations are part of the ZTF public survey and serendipitously
covered the GRB localization. We obtained a series of g-band images
beginning at 02:48:56.6 UT on 2019 Nov 01 (5.4 hours after the burst
trigger time). This corresponds to ~68% of the probability enclosed in the
GBM localization region and the totality of the Swift region.
The images were processed through the ZTF reduction and image subtraction
pipelines at IPAC to search for potential counterparts. No
high-significance transients were identified by our pipeline in the area
observed.
The median 5 sigma upper limit for an isolated point source in our images
was g > 20.8 mag for these observations.
ZTF is a project led by PI S. R. Kulkarni at Caltech (see ATEL #11266
<http://www.astronomerstelegram.org/?read=11266>), and includes IPAC; WIS,
Israel; OKC, Sweden; JSI/UMd, USA; UW, USA; DESY, Germany; NRC, Taiwan; UW
Milwaukee, USA and LANL USA. ZTF acknowledges the generous support of the
NSF under AST MSIP Grant No 1440341. Alert distribution service provided by
DIRAC@UW. Alert filtering is being undertaken by the GROWTH marshal system,
supported by NSF PIRE grant 1545949.
GCN Circular 26149
Subject
Konus-Wind observation of GRB 191031D: correction to GCN 26126
Date
2019-11-03T11:15:05Z (6 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
D. Frederiks, on behalf of the Konus-Wind team:
Reported in Frederiks et al. 2019 (GCN Circ. 26126),
the KW spectral parameters and fluxes of short/hard GRB 191031D
are incorrect due to wrong instrument calibrations used.
The correct values are given below.
As observed by Konus-Wind, the burst had a fluence
of 5.72(-0.63,+0.69)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0-0.016 s,
of 4.12(-0.72,+0.80)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum of the burst (measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 15 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.12(-0.18,+0.20)
and Ep = 735(-92,+112) keV (chi2 = 32/39 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.9
(chi2 =32/38 dof).
I apologize for possible inconvenience this may have caused.
GCN Circular 26147
Subject
GRB 191031D: Gemini optical upper limit
Date
2019-11-02T19:25:43Z (6 years ago)
From
Eleonora Troja at NASA/GSFC/UMD <eleonora@umd.edu>
S.Dichiara (UMD, NASA-GSFC) and E. Troja (UMD, NASA-GSFC) report on behalf
of a larger collaboration:
We observed the field of the short duration GRB 191031D (Fermi GBM Team,
GCN Circ. 26111; D'Elia et al., GCN Circ. 26112) with the Gemini North
8-meter telescope located on Mauna Kea, beginning on 2019-11-02 04:43:08
UT, approximately 1.3 d post-burst. We obtained a series of 6x120s r-band
images using the Gemini Multi-Object Spectrograph (GMOS).
No credible counterpart is detected within the enhanced X-ray position
(Osborne el al., GCN 26117) down to r > 25 AB mag, not corrected for
Galactic extinction.
We thank S. Stewart and the Gemini North staff for executing these
observations.
GCN Circular 26134
Subject
GRB 191031D: MMT Binospec Optical Upper Limit
Date
2019-11-01T20:39:58Z (6 years ago)
From
Kerry Paterson at Northwestern <kerry.paterson@northwestern.edu>
K. Paterson, W. Fong, K. D. Alexander, G. Schroeder, A. Rouco Escorial (Northwestern) report:
���We observed the field of the short-duration GRB 191031D (Fermi-GBM et al., GCN 26111; D'Elia et al., GCN 26112; Mailyan et al., GCN 26118) with Binospec mounted on the 6.5-m MMT on Mount Hopkins, Arizona, starting on 2019 November 1 at 01:44:13 UT, 4.31 hours after the burst. We obtained 15x120-sec of observations in the r-band in 1.05��� seeing and clear conditions.
We do not detect any optical source in or around the enhanced XRT position (Osborne et al. GCN 26117).
We obtain a 3-sigma upper limit of r > 23.5 AB mag on the afterglow or any coincident host galaxy, not corrected for Galactic extinction. Photometry is calibrated to the USNO-B1.0 catalog. This limit is consistent with, and slightly deeper than the limit found by Butler et al. (GCN 26121). We note that the closest, clearly-extended source is 5.48 arcsec to the southwest.
Further observations are planned. We thank the MMT staff, and in particular observer Michael Calkins, for their assistance with these observations.���
GCN Circular 26133
Subject
GRB 191031D: Swift-BAT refined analysis
Date
2019-11-01T19:07:47Z (6 years ago)
From
Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>
T. Sakamoto (AGU), S. D. Barthelmy (GSFC), V. D'Elia (SSDC),
H. A. Krimm (NSF), S. Laha (GSFC/UMBC), A. Y. Lien (GSFC/UMBC),
C. B. Markwardt (GSFC), J. P. Norris (BSU), D. M. Palmer (LANL),
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 191031D (trigger #932608)
(D'Elia, et al., GCN Circ. 26112). The BAT ground-calculated position is
RA, Dec = 283.269, 47.645 deg which is
RA(J2000) = 18h 53m 04.5s
Dec(J2000) = +47d 38' 40.9"
with an uncertainty of 1.4 arcmin, (radius, sys+stat, 90% containment).
The partial coding was 37%.
The mask-weighted light curve shows a multi-peak structure from T-0.05 sec to T+0.3 sec
with a harder first pulse and softer second pulse. There is no sign of extended emission.
T90 (15-350 keV) is 0.29 +- 0.05 sec (estimated error including systematics).
The time-averaged spectrum from T-0.03 to T+0.31 sec is best fit by a simple
power-law model. The power law index of the time-averaged spectrum is
0.80 +- 0.15. The fluence in the 15-150 keV band is 4.1 +- 0.4 x 10^-7 erg/cm2.
The 1-sec peak photon flux measured from T-0.36 sec in the 15-150 keV band
is 4.3 +- 0.4 ph/cm2/sec. All the quoted errors are at the 90% confidence
level.
The duration and hardness of GRB 191031D place it squarely within the distribution of
short, hard bursts detected by BAT. Using the 4-ms binned light curve, the spectral lag
of the burst is 0.2 ms +- 2 ms for the 50-100 keV to 15-25 keV bands, and 0.4 ms +- 3 ms
for the 100-350 keV to 25-50 keV bands. These values are consistent with a short GRB.
The results of the batgrbproduct analysis are available at
http://gcn.gsfc.nasa.gov/notices_s/932608/BA/
GCN Circular 26129
Subject
GRB 191031D: AstroSat CZTI detection
Date
2019-11-01T18:46:38Z (6 years ago)
From
Ramkrishna Gaikwad at IUCAA/AstroSat <ramkrishna@iucaa.in>
R. Gaikwad, S. Gupta, V. Sharma and D. Bhattacharya (IUCAA), V. Bhalerao (IIT-B), A. R. Rao (TIFR) and S. Vadawale (PRL) report on behalf of the AstroSat CZTI collaboration:
Analysis of AstroSat CZTI data showed the detection of a GRB 191031D, which was also detected by Fermi GBM Real-time Localization (GCN #26111), Swift (D'Elia et al., GCN #26112), Swift-XRT (Osborne et al., GCN #26117), Fermi GBM (Mailyan et al., GCN #26118), VLA (Laskar T. et al., GCN #26120), RATIR (Butler N. et al., GCN #26121), COATLI (Watson A. M. et al., GCN #26122), AGILE/MCAL (Ursi A. et al., GCN #26123), MITSuME Akeno (Ogawa F. et al., GCN #26125) and Konus-Wind (Frederiks D. et al., GCN #26126).
The source was clearly detected in the 40-200 keV energy range. The light curve showed single pulse of emission peaking at 2019-10-31 21:23:31.0 UT. The measured peak count rate associated with the burst is 628 cts/s above the background in the combined data of four quadrants, with a total of 393 cts. The local mean background count rate was 556 cts/s. Using cumulative rates, we measure a T90 of 0.35 s.
It was also clearly detected in the CsI anticoincidence (Veto) detector in the 100-500 keV energy range.
CZTI GRB detections are reported regularly on the payload site at http://astrosat.iucaa.in/czti/?q=grb. CZTI is built by a TIFR-led consortium of institutes across India, including VSSC, ISAC, IUCAA, SAC and PRL. The Indian Space Research Organisation funded, managed and facilitated the project.
GCN Circular 26128
Subject
GRB 191031D: Swift/UVOT Upper Limits
Date
2019-11-01T17:00:34Z (6 years ago)
From
Sam LaPorte at PSU <sjl5346@psu.edu>
GRB 191031D: Swift/UVOT Upper Limits
J. D. Gropp (PSU) and V. D'Elia (SSDC)
report on behalf of the Swift/UVOT team:
The Swift/UVOT began settled observations of the field of GRB 191031D
93 s after the BAT trigger (D'Elia et al., GCN Circ. 26112).
No optical afterglow consistent with the XRT position
(Osborne et al. GCN Circ. 26117)
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 93 242 147 >20.8
u_FC 306 555 246 >20.2
white 93 6694 575 >21.1
v 636 5863 294 >19.9
b 561 6683 471 >20.4
u 306 6477 697 >20.3
w1 686 6273 452 >19.8
m2 661 6067 294 >19.6
w2 612 5658 294 >19.9
The magnitudes in the table are not corrected for the Galactic extinction
due to the reddening of E(B-V) = 0.08 in the direction of the burst
(Schlegel et al. 1998).
GCN Circular 26126
Subject
Konus-Wind observation of GRB 191031D
Date
2019-11-01T11:56:53Z (6 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
D. Frederiks, S. Golenetskii, R. Aptekar, A. Lysenko,
A. Ridnaia, D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline
on behalf of the Konus-Wind team, report:
The short-duration GRB 191031D
(Swift detection: D'Elia et al., GCN Circ. 26112;
Fermi GBM detection: Mailyan & Meegan, GCN Circ. 26118;
AGILE/MCAL observations: Ursi et al., GCN Circ. 26123)
triggered Konus-Wind at T0=77011.324 s UT (21:23:31.324).
The burst light curve shows a mult-peaked pulse
which started at ~T0-0.064 s and had a total duration of ~0.35 s.
The emission is seen up to ~5 MeV.
As observed by Konus-Wind, the burst
had a fluence of 2.72(-0.27, +0.31)x10^-6 erg/cm2,
and a 16-ms peak flux, measured from T0-0.016 s,
of 1.95(-0.32,+0.38)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum of the burst
(measured from T0 to T0+0.256 s)
is best fit in the 20 keV - 15 MeV range
by a power law with exponential cutoff model:
dN/dE ~ (E^alpha)*exp(-E*(2+alpha)/Ep)
with alpha = -0.27(-0.17,+0.20)
and Ep = 370(-46,+58) keV (chi2 = 35/39 dof).
Fitting by a GRB (Band) model yields the same alpha and Ep,
and an upper limit on the high energy photon index: beta < -2.6
(chi2 =35/38 dof).
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB191031_T77011/
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
GCN Circular 26125
Subject
GRB 191031D: MITSuME Akeno optical upper limits
Date
2019-11-01T10:51:07Z (6 years ago)
From
Ogawa Futa at Tokyo Institute of Technology <ogawa@hp.phys.titech.ac.jp>
F. Ogawa, R. Adachi, K. L. Murata, M. Oeda, K.Shiraishi, K. Iida, M.
Niwano,
R. Hosokawa, S. Toma, Y. Yatsu, and N. Kawai (TokyoTech)
report on behalf of the MITSuME collaboration:
We searched for the optical counterpart of GRB 191031D (The Fermi GBM
team, GCN Circular #26111, V. D'Elia et al., GCN Circular #26112, Bagrat
Mailyan, #26114) with the optical three color (g', Rc, and Ic) CCD
cameras attached to the MITSuME 50 cm telescope of Akeno
Observatory, Yamanashi, Japan.
The observation started on 19/11/01 08:18:36 UT. We did not find any new
point
sources within the XRT circle (J.P. Osborne et al., GCN Circular #26117)
in all three bands.
We obtained the following 5-sigma limits for the magnitudes.
T0+[hour]���� MID-UT������ T-EXP[sec]������ 5-sigma limits
------------------------------------------------------------------------------------------------
��~11.5���������������� 09:12:34������ 1680�������������������������� g'>18.3, Rc>18.2, Ic>17.3
------------------------------------------------------------------------------------------------
T0+ : Elapsed time after the burst
T-EXP: Total Exposure time
We used UCAC4 catalog for flux calibration.
The magnitudes are expressed in the AB system.
GCN Circular 26124
Subject
GRB 191031D: Swift-XRT refined Analysis
Date
2019-11-01T09:29:57Z (6 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
B. Sbarufatti (PSU), D.N. Burrows (PSU), J. D. Gropp (PSU), A.P.
Beardmore (U. Leicester), P.A. Evans (U. Leicester), J.P. Osborne (U.
Leicester), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) , M.
Capalbi (INAF-IASFPA) and V. D'Elia report on behalf of the Swift-XRT
team:
We have analysed 6.2 ks of XRT data for GRB 191031D (D'Elia et al. GCN
Circ. 26112), from 101 s to 17.5 ks after the BAT trigger. The data
are entirely in Photon Counting (PC) mode. The enhanced XRT position
for this burst was given by Osborne et al. (GCN Circ. 26117).
The light curve can be modelled with a power-law decay with a decay
index of alpha=2.04 (+0.22, -0.21).
A spectrum formed from the PC mode data can be fitted with an absorbed
power-law with a photon spectral index of 1.90 (+0.26, -0.16). The
best-fitting absorption column is consistent with the Galactic value
of 6.6 x 10^20 cm^-2 (Willingale et al. 2013). The counts to observed
(unabsorbed) 0.3-10 keV flux conversion factor deduced from this
spectrum is 3.3 x 10^-11 (3.8 x 10^-11) erg cm^-2 count^-1.
A summary of the PC-mode spectrum is thus:
Total column: 6.6 (+/-2.1) x 10^20 cm^-2
Galactic foreground: 6.6 x 10^20 cm^-2
Excess significance: <1.6 sigma
Photon index: 1.90 (+0.26, -0.16)
If the light curve continues to decay with a power-law decay index of
2.04, the count rate at T+24 hours will be 1.9 x 10^-6 count s^-1,
corresponding to an observed (unabsorbed) 0.3-10 keV flux of 6.2 x
10^-17 (7.1 x 10^-17) erg cm^-2 s^-1.
The results of the XRT-team automatic analysis are available at
http://www.swift.ac.uk/xrt_products/00932608.
This circular is an official product of the Swift-XRT team.
GCN Circular 26123
Subject
GRB 191031D: AGILE/MCAL observations
Date
2019-11-01T09:11:45Z (6 years ago)
From
Alessandro Ursi at INAF/IAPS <alessandro.ursi@gmail.com>
A. Ursi (INAF/IAPS), F. Verrecchia (SSDC, and INAF/OAR), M. Tavani
(INAF/IAPS, and Univ. Roma Tor Vergata), M. Cardillo, C. Casentini, G.
Piano (INAF/IAPS), F. Lucarelli, C. Pittori (SSDC, and INAF/OAR), A.
Bulgarelli, V. Fioretti, N. Parmiggiani (INAF/OAS-Bologna), M. Pilia, A.
Trois (INAF/OA-Cagliari), I. Donnarumma (ASI), F. Longo (Univ. Trieste and
INFN Trieste), report on behalf of the AGILE Team:
The AGILE Mini-CALorimeter (MCAL) detected the short GRB 191031D at T0 =
2019-10-31 21:23:28.17 +/- 0.01 s (UTC), already detected by Fermi/GBM (GCN
#26111), Swift (D'Elia et al., 2019; GCN #26112), and INTEGRAL/SPIACS
(trignum=8402).
The event lasted about 0.2 s and released a total number of ~430 counts in
the detector (in the 0.4-100 MeV energy range), above an average background
rate of 544 counts / s.
The light curve shows a single peak episode and can be found at
http://www.agilescienceapp.it/notices/GRB_064997_499641808.174626.png.
The AGILE-MCAL detector is a CsI detector with a 4 pi FoV, sensitive in the
energy range 0.4-100 MeV. Additional analysis of AGILE data is in progress.
GCN Circular 26122
Subject
GRB 191031D: COATLI Optical Observations
Date
2019-11-01T05:13:02Z (6 years ago)
From
Alan M Watson at UNAM <alan@astro.unam.mx>
Alan M. Watson (UNAM), Nat Butler (ASU), Rosa L. Becerra (UNAM), Diego Gonz��lez
(UNAM), Alexander Kutyrev (GSFC), William H. Lee (UNAM), Margarita Pereyra
(UNAM), and Eleonora Troja (GSFC) report:
We observed the field of GRB 191031A (D'Ai et al., GCN Circ. 26101; Fermi GBM
Team, GCN Circ. 26102) with the COATLI 50-cm telescope and interim imager at the
Observatorio Astron��mico Nacional on the Sierra de San Pedro M��rtir
(http://coatli.astroscu.unam.mx) from 2019-11-01 02:47 UTC to 04:49 UTC (5.4 to
7.4 hours after the trigger), obtaining a total of 4530 seconds of exposure in
the w filter.
We do not detetect any uncataloged sources in the enhanced XRT error region
(Osborne et al., GCN Circ. 26117) to a 3-sigma limit of w = 23.2.
Our w magnitudes are calibrated against the Pan-STARRS1 catalog, are on an
approximate AB system (Becerra et al., 2019, ApJ, 872, 118), and are not
corrected for Galactic extinction in the direction of the GRB.
We thank the COATLI technical team and the staff of the Observatorio Astron��mico
Nacional.
GCN Circular 26121
Subject
GRB 191031D: RATIR Optical and NIR Observations
Date
2019-11-01T04:40:51Z (6 years ago)
From
Alan M Watson at UNAM <alan@astro.unam.mx>
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 191031D (Fermi GBM Team, GCN Circ. 26111; D'Elia et
al., GCN Circ. 26112) 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 2019/11 1.09 to 2019/11
1.12 UTC (4.65 to 5.49 hours after the BAT trigger), obtaining a total of 0.56
hours exposure in the r and i bands, 0.23 hours exposure in the Z and Y
bands, and 0.06 hours exposures in the J and H bands.
For a source within the Swift-XRT error circle, in comparison with the USNO-B1
and 2MASS catalogs, we obtain the following upper limits (3-sigma):
r > 22.94
i > 23.17
Z > 21.50
Y > 21.40
J > 19.44
H > 19.33
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 26120
Subject
GRB 191031D: VLA 9.8 GHz upper limit
Date
2019-11-01T04:14:06Z (6 years ago)
From
Wen-fai Fong at Northwestern U <wfong@northwestern.edu>
T. Laskar (Bath), W. Fong, K. D. Alexander, G. Schroeder, K. Paterson (Northwestern) and E. Berger (Harvard) report:
"We observed the position of the short-duration GRB 191031D (Fermi-GBM et al., GCN 26111; D'Elia et al., GCN 26112; Mailyan et al., GCN 26118) with the Karl G. Jansky Very Large Array (VLA) under Program 19B-217 (PI: Fong) beginning on 2019 Oct 31.992 UT (2.4 hr post-burst) at a mean frequency of 9.8 GHz. Based on preliminary analysis, in 1 hour of observations we do not detect any radio emission at or near the position of the XRT afterglow (Osborne et al., GCN 26117) to a 3-sigma limit of 15 microJy. Additional, detailed analysis is ongoing.
We thank Amy Mioduszewski and the rest of the VLA staff for their assistance with rapidly approving and executing these observations. Further observations are planned."
GCN Circular 26118
Subject
GRB 191031D: Fermi GBM detection
Date
2019-11-01T03:22:35Z (6 years ago)
From
Bagrat Mailyan at UAH <bm0054@uah.edu>
B. Mailyan (UAH) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 21:23:31.13 UT on 31 October 2019, the Fermi Gamma-Ray Burst Monitor
(GBM)
triggered and located GRB 191031D (trigger 594249816/191031891)
which was also detected by the Swift BAT and XRT (D'Elia et al. 2019, GCN
26112)
The Fermi GBM Final Real-time Localization (GCN 26111) is consistent with
the Swift position.
The angle from the Fermi LAT boresight at the GBM trigger time is 64
degrees.
The GBM light curve shows a short spike with a duration (T90) of about
0.256 s (50-300 keV).
The time-averaged spectrum from T0-0.064 s to T0+0.32 s is
best fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.42 +/- 0.04 and
the cutoff energy, parameterized as Epeak, is 856 +/- 53 keV
The event fluence (10-1000 keV) in this time interval is
(4.36 +/- 0.09)E-06 erg/cm^2. The 64 ms peak photon flux measured
starting from T0+0.128 s in the 10-1000 keV band
is 48.7 +/- 1.59 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 26117
Subject
GRB 191031D: Enhanced Swift-XRT position
Date
2019-11-01T00:27:16Z (6 years ago)
From
Phil Evans at U of Leicester <pae9@leicester.ac.uk>
J.P. Osborne, A.P. Beardmore, P.A. Evans and M.R. Goad (U. Leicester)
report on behalf of the Swift-XRT team.
Using 722 s of XRT Photon Counting mode data and 1 UVOT
images for GRB 191031D, 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 = 283.28951, +47.64407 which is equivalent
to:
RA (J2000): 18h 53m 9.48s
Dec (J2000): +47d 38' 38.6"
with an uncertainty of 1.9 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 26114
Subject
Correction in name: GRB 191031D (not GRB 191031C)
Date
2019-10-31T22:21:14Z (6 years ago)
From
Bagrat Mailyan at UAH <bm0054@uah.edu>
B. Mailyan (UAH) reports on behalf of the Fermi GBM Team:
"The Fermi Gamma-ray Burst Monitor (GBM) trigger 594249816/191031891
at 21:23:31 UT on 31 Oct 2019, of GRB 191031C (GCN Circ. #26111) should be
GRB 191031D.
We apologize for any confusion caused.���
GCN Circular 26112
Subject
GRB 191031D: Swift detection of a short hard burst
Date
2019-10-31T21:53:41Z (6 years ago)
From
Hans Krimm at NSF/NASA-GSFC <hkrimm@nsf.gov>
V. D'Elia (SSDC), E. Ambrosi (INAF-IASFPA), A. D'Ai (INAF-IASFPA),
J.D. Gropp (PSU), J. A. Kennea (PSU), N. J. Klingler (PSU),
H. A. Krimm (NSF), D. M. Palmer (LANL) and A. Tohuvavohu (U Toronto)
report on behalf of the Neil Gehrels Swift Observatory Team:
At 21:23:31 UT, the Swift Burst Alert Telescope (BAT) triggered and
located GRB 191031D (trigger=932608). Swift slewed immediately to the burst.
The BAT on-board calculated location is
RA, Dec 283.275, +47.639 which is
RA(J2000) = 18h 53m 06s
Dec(J2000) = +47d 38' 19"
with an uncertainty of 3 arcmin (radius, 90% containment, including
systematic uncertainty). The BAT light curve showed a single peak
structure with a duration of about 0.4 sec. The peak count rate
was ~18000 counts/sec (15-350 keV), at ~0 sec after the trigger.
The XRT began observing the field at 21:24:59.8 UT, 88.8 seconds after
the BAT trigger. Using promptly downlinked data we find a fading,
uncatalogued X-ray source with an enhanced position: RA, Dec 283.2890,
47.6438 which is equivalent to:
RA(J2000) = 18h 53m 09.37s
Dec(J2000) = +47d 38' 37.7"
with an uncertainty of 2.3 arcseconds (radius, 90% containment). This
location is 38 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.
UVOT took a finding chart exposure of 150 seconds with the White filter
starting 92 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
0.08.
This GRB was also detected by Fermi/GBM (trignum=191031891, GCN
26111), and the INTEGRAL/SPIACS event (trignum=8402). We note that the
Fermi automated circular has misnamed this event GRB 191031C.
Burst Advocate for this burst is V. D'Elia (delia AT ssdc.asi.it).
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/)