GRB 191001A
GCN Circular 25942
Subject
GRB 191001A: Swift-XRT observations
Date
2019-10-03T20:26:43Z (6 years ago)
From
Antonino D'Ai at IASF-PA <antonino.dai@inaf.it>
D.N. Burrows (PSU), J. D. Gropp (PSU), A. Tohuvavohu (U. Toronto), K.L.
Page (U. Leicester), A.P. Beardmore (U. Leicester), P. D'Avanzo
(INAF-OAB), M.G. Bernardini (INAF-OAB), E. Ambrosi (INAF-IASFPA) and
P.A. Evans (U. Leicester) report on behalf of the Swift-XRT team:
Swift-XRT has performed follow-up observations of the Fermi/GBM
detected burst GRB 191001A (GCN Circ. 25893, 25894), collecting 5.2 ks
of Photon Counting (PC) mode data between T0+114.2 ks and T0+161.3 ks.
No X-ray sources have been detected consistent with being within 2.0
arcsec of the likely associated optical transient AT2019rog (GCN Circ.
25911, 25918, 25919 and Tonry et al., TNSTR 1954). The 3-sigma upper
limit in the field ranges from ~0.002 to ~0.003 ct s^-1, corresponding
to a 0.3-10 keV observed flux of 8.6e-14 to 1.0e-13 erg cm^-2 s^-1
(assuming a typical GRB spectrum).
The results of the XRT-team automatic analysis of the XRT observations,
including a position-specific upper limit calculator, are available at
https://www.swift.ac.uk/ToO_GRBs/00020949.
This circular is an official product of the Swift-XRT team.
GCN Circular 25938
Subject
GRB 191001A: Fermi GBM observation
Date
2019-10-03T17:42:48Z (6 years ago)
From
Rachel Hamburg at UAH <rkh0007@uah.edu>
E. Bissaldi (Politecnico & INFN Bari), R. Hamburg (UAH)
and C. Meegan (UAH) report on behalf of the Fermi GBM Team:
"At 06:41:50.58 UT on 1 October 2019, the Fermi Gamma-Ray
Burst Monitor (GBM) triggered and located GRB 191001A
(trigger 591604915 / 191001279). The on-ground calculated
location has been reported in GCN #25893, and an IPN
annulus consistent with the GBM localization was reported
in GCN #25926. The ATLAS and DDOTI (GCN #25911) optical
counterpart position are consistent with the GBM localization.
The GBM light curve consists of several pulses
with a duration (T90) of about 24 s (50-300 keV).
The time-averaged spectrum from T0-4.99 s to T0+25.73 s
is best fit by a power law function with an exponential
high-energy cutoff. The power law index is -0.8 +/- 0.1
and the cutoff energy, parameterized as Epeak, is 114 +/- 9 keV.
The event fluence (10-1000 keV) in this time interval is
(4.7 +/- 0.2)E-06 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+15.7 s in the 10-1000 keV band
is 10.5 +/- 0.4 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 25926
Subject
IPN triangulation of GRB 191001A
Date
2019-10-02T18:21:00Z (6 years ago)
From
Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>
D. Svinkin, S. Golenetskii, R. Aptekar, D. Frederiks, A. Kozlova,
and T. Cline on behalf of the Konus-Wind team,
K. Hurley, on behalf of the IPN, and
A. Goldstein, M. S. Briggs, and C. Wilson-Hodge
on behalf of the Fermi GBM team, report:
The long duration GRB 191001A
(Fermi-GBM detection: The Fermi GBM team, GCN Circ. 25893;
BALROG localization: Burgess et al., GCN Circ. 25894)
was detected by Fermi (GBM trigger 591604915), Konus-Wind,
and Swift (BAT) at about 24110 s UT (06:41:50).
The burst was outside the coded field of view of the BAT.
We have triangulated this GRB to a Konus-GBM annulus centered at
RA(2000)=346.113 deg (23h 04m 27s) Dec(2000)=-7.939 deg (-7d 56' 21"),
whose radius is 46.475 +/- 2.251 deg (3 sigma).
The distance between the optical transient ATLAS19wxr
(Smartt, et al., GCN Circ. 25922; Pereyra et al., GCN Circ. 25911)
and the annulus center line is 9.3 arcmin,
supporting the association of the transient and the GRB.
This annulus may be improved.
A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB191001_T24130/IPN
GCN Circular 25924
Subject
GRB 191001A: Swift ToO observations
Date
2019-10-02T14:08:17Z (6 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/GBM GRB 191001A.
Automated analysis of the XRT data will be presented online at
https://www.swift.ac.uk/ToO_GRBs/00020949
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/GBM 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 25919
Subject
GRB 191001A: KAIT Optical Upper Limit
Date
2019-10-02T05:54:41Z (6 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 the GBM GRB 191001A (Fermi GBM team,
GCN 25893) starting at ~21.8 hours after the burst. We observed
the afterglow candidate AT2019rog, which was discovered independently
by ATLAS (Tonry et al., TNSTR 1954) and DDOTI (Pereyra et al., GCN 25911),
obtaining 17 x 60s images in the clear (roughly R) filters. We do not
detect the afterglow candidate in our co-add images with limiting mag
of ~21.5. Our non-detection result is consistent with observations from
RATIR (Pereyra et al., GCN 25918