GRB 181126B
GCN Circular 23515
Subject
GRB 181126B: Zwicky Transient Facility Follow-Up of a Fermi Short GRB (Trigger 564897175)
Date
2018-12-07T05:14:50Z (7 years ago)
From
Tomas Ahumada at U. of Maryland <tahumada@astro.umd.edu>
Authors: Tomas Ahumada (UMD), Michael W. Coughlin (Caltech), S. Bradley
Cenko (NASA GSFC), Leo P. Singer (NASA GSFC), Shaon Ghosh (UWM), Igor
Andreoni (Caltech), Mansi M. Kasliwal (Caltech), Eric C. Bellm (UW), V.
Zach Golkhou (UW), Ryosuke Itoh (Tokyo Tech), Anna Ho (Caltech), Yuhan Yao
(Caltech), Jacob Jencson (Caltech), Matt Hankins (Caltech), Kishalay De
(Caltech), Virginia Cunningham (UMD) on behalf of the ZTF and GROWTH
collaborations and the KPED team
We observed the localization region of the short GRB181126B (trigger
564897175) detected by 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. We obtained two sets of 180
second r-band images covering 1400 square degrees beginning at 5:15 UT on
2018 November 26 (1 hour and 23 minutes after the burst trigger time).
Accounting for area lost to processing failures, this corresponds to
analyzing 66% of the probability enclosed. Beginning at 6:06 UT on 2018
November 27 we observed the updated IPN localization with ZTF using 300
second r-band exposures. The observations covered 709 square degrees. Once
again accounting for processing failures, 77% of the enclosed probability
was analyzed.
The images were processed through the ZTF reduction and image subtraction
pipelines at IPAC to search for potential counterparts. 394
high-significance transient and variable candidates were identified by our
pipeline in the area observed, most (383) of which had previous detections
with ZTF in the days and weeks prior to the GRB trigger time (e.g.,
supernovae, active galactic nuclei, CV).
Further follow-up of 11 transients was obtained with the Kitt Peak EMCCD
Demonstrator (KPED) on the Kitt Peak 84-inch telescope on November 28.
Additionally, we obtained follow-up spectroscopy of 6 candidates with the
Low Resolution Imaging Spectrometer (LRIS) on Keck I, the nights of
December 1 and December 3. The candidates are listed below, however no
photometric evolution or spectral classification was consistent with an
optical counterpart.
----------------------------------------------------------------------------------------------------------------------------
ZTF ID RA DEC last non-detection discovery KPED
Classification
----------------------------------------------------------------------------------------------------------------------------
deg deg date in 2018 Nov 26 Nov 28
----------------------------------------------------------------------------------------------------------------------------
ZTF18achtkfy 103.5113 37.0748 11-09 g<19.94 r = 19.69 r = 20.95
SN* (Rising)
ZTF18acpftxl 102.7187 29.3472 11-21 r<20.43 r = 20.11 r > 20.93
Asteroid* (1 det)
ZTF18achflqs 70.2895 23.8902 11-10 r<20.37 r = 20.74 r = 20.26 SN*
(Rising)
ZTF18acrkcxa 73.7605 22.6787 11-21 r<19.68 r = 21.21 r = 20.87 SN*
(Rising)
ZTF18acrkkpc 95.8148 10.323 11-21 r<20.17 r = 20.17 r = 19.85 SN*
(Rising)
ZTF18aadwfrc 94.3249 50.4844 11-25 r<19.33 r = 18.96 r = 18.13 SN
II z=0.04
ZTF18acrfond 59.8623 24.589 11-25 r<19.38 r = 19.93 r = 18.87 SN
Ia z=0.117
ZTF18acrfymv 94.5049 44.1813 11-25 r<19.13 r = 20.05 r = 19.60 S
NIc-BL
<http://skipper.caltech.edu:8080/cgi-bin/growth/edit_comment.cgi?name=ZTF18acrfymv&id=11173>
z=0.
<http://skipper.caltech.edu:8080/cgi-bin/growth/edit_comment.cgi?name=ZTF18acrfymv&id=11174>
072
ZTF18acptgzz 68.3852 -1.6475 11-25 r<19.22 r = 19.01 r = 19.04 SN
Ia z=0.096
ZTF18acbyrll 88.8695 29.4723 11-21 r<19.84 r = 18.79 r > 21.87
Asteroid* (1 det)
ZTF18acrewzd 70.3221 -1.7688 11-25 r<19.17 r = 20.21 r = 19.9 SN
Ia z=0.13
-------------------------------------------------------------------------------------------------------------------------
*Classification from photometric data points.
The median 5-sigma upper limit for an isolated point source in ZTF images
was r > 20.5 mag for the observations made on November 26 and r > 21.1 mag
for the observations made on November 27.
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; MOST, 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 23523
Subject
GRB 181126B: KAIT Follow-Up Observations of a Fermi Short GRB (Trigger 564897175)
Date
2018-12-12T19:45:56Z (6 years ago)
From
Weikang Zheng at UC Berkeley <weikang@berkeley.edu>
WeiKang Zheng, Keto Zhang, Alexei V. Filippenko, and Sergiy Vasylyev
(UC Berkeley) report on behalf of the KAIT GRB team:
The 0.76-m Katzman Automatic Imaging Telescope (KAIT), located at
Lick Observatory, observed the field of the short GRB181126B (trigger
564897175) detected by the GBM on the Fermi satellite.
More than one thousand galaxies were selected from the
Glade catalog (http://aquarius.elte.hu/glade/) according to
their priority score. On 2018 Nov. 26 UT, KAIT observed 236 of them having
top-priority scores, with each clear-filter exposure time being 60 s.
The first image was taken at 07:41:13 UT, about 3.8 hr after the burst, and
the last image at 11:51:09 UT. Template images were obtained on 2018
Dec. 8 and 9. The images were processed through the KAIT
subtraction pipeline to search for potential optical counterparts.
13 known asteroids were detected, but we found no credible transient
that might be the optical afterglow of this GRB. None of the 11
transients reported by Ahumada et al. (GCN 23515) was in the field of
view of the KAIT images. Our typical limiting mag is 19.0, although some
fields have a shallower limiting mag owing to moonlight.