LIGO/Virgo S200105ae
GCN Circular 26837
Subject
LIGO/Virgo S200105ae: Upper limits from Konus-Wind observations
Date
2020-01-21T08:56:07Z (6 years ago)
From
Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru>
A. Ridnaia, S. Golenetskii, R.Aptekar, D. Frederiks,
M. Ulanov, D. Svinkin, A. Tsvetkova, A. Lysenko, and T. Cline,
on behalf of the Konus-Wind team, report:
Konus-Wind (KW) was observing the whole sky at the time of the
LIGO/Virgo event S200105ae (2020-01-05 16:24:26.057 UTC, hereafter T0;
LIGO/Virgo Collaboration GCN Circ. 26640).
No triggered KW GRBs happened ~4 days before and ~6 days
after T0. The closest waiting-mode GRB was observed ~5 hours after T0.
Using waiting-mode data within the interval T0 +/- 100 s,
we found no significant (> 5 sigma) excess over the background
in both KW detectors on temporal scales from 2.944 s to 100 s.
We estimate an upper limit (90% conf.) on the 20 - 1500 keV fluence
to 9.2x10^-7 erg/cm^2 for a burst lasting less than 2.944 s and having a
typical KW short GRB spectrum (an exponentially cut off power law with
alpha =-0.5 and Ep=500 keV). For a typical long GRB spectrum (the Band
function with alpha=-1, beta=-2.5, and Ep=300 keV), the corresponding
limiting peak flux is 2.5x10^-7 erg/cm^2/s (20 - 1500 keV, 2.944 s scale).
All the quoted values are preliminary.
GCN Circular 26810
Subject
LIGO/Virgo S200105ae: More candidates from the Zwicky Transient Facility
Date
2020-01-18T03:33:23Z (6 years ago)
From
Tomas Ahumada at U. of Maryland <tahumada@astro.umd.edu>
Tomas Ahumada (UMD), Igor Andreoni (Caltech), Viraj Karambelkar (Caltech),
Gaurav Waratkar (IITB), Harsh Kumar (IITB), Shreya Anand (Caltech), Michael
W. Coughlin (Caltech), Leo Singer (NASA GSFC), Mansi M. Kasliwal (Caltech),
Simeon Reusch (DESY), Robert Stein (DESY), Matthew Graham (Caltech), Jesper
Sollerman (OKC)
on behalf of the Zwicky Transient Facility (ZTF) and Global Relay of
Observatories Watching Transients Happen (GROWTH) collaborations
We serendipitously observed the localization region of the gravitational
wave trigger S200105ae (LVC, GCN #26640) with the Palomar 48-inch telescope
equipped with the 47 square degree Zwicky Transient Facility camera (ZTF,
Bellm et al. 2019, Graham et al. 2019) during the regular ZTF survey (i.e.,
without triggering further ToO observations in addition to those described
in Anand et al, GCN #26662). The images were processed in real-time through
the ZTF reduction and image subtraction pipelines at IPAC (Masci et al.
2019).
We queried the ZTF alert stream using Kowalski (Duev et al., 2019) and
AMPEL (Nordin et al., 2019), requiring at least 2 detections separated by
at least 15 minutes to select against moving objects. Furthermore, we
cross-matched our candidates with the Minor Planet Center to flag known
asteroids. We require that no spatially coincident ZTF alert has been
issued before the detection time of S200105ae. New candidates were found
within the 95% probability contour of S200105ae, in addition to those
reported by Stein et al. (GCN #26673). The new transient candidates are
presented in the table below.
+--------------+-----------+-------------+--------------+--------+------+----------+-----------+
| Name | IAU Name | RA | Dec | filter | mag |
MJD | Notes |
+--------------+-----------+-------------+--------------+--------+------+----------+-----------+
| ZTF20aaexpwt | AT2020adi | 06:26:01.30 | +11:33:38.85 | r | 19.8 |
58864.31 | (a)(d) |
| ZTF20aaertil | AT2020pu | 14:52:25.86 | +31:01:18.50 | g | 19.7 |
58863.45 | (b)(c)(1) |
| ZTF20aaevbzl | AT2020adf