ZTF23aaarlti
GCN Circular 33233
Subject
ZTF23aaarlti/AT2023avj: VLA radio detection
Date
2023-01-29T17:46:54Z (2 years ago)
From
Daniel Perley at Liverpool JMU <d.a.perley@ljmu.ac.uk>
D. A. Perley (LJMU) and A. Y. Q. Ho (Cornell) report on behalf of a larger collaboration:
We observed the location of the fast optical transient AT2023avj (ZTF23aaarlti; Wang et al., GCN 33226 and AstroNote 2023-17) using the Karl G. Jansky Very Large Array (VLA) on 2023 January 28 between 06:48 and 07:28 (UT). Observations were carried out using the X-band receivers at a mean frequency of 10 GHz.
We detect a strong source at a location of RA = 09:39:20.7894, Dec=+58:08:12.619 (J2000; RMS statistical accuracy +/- 0.01"), consistent with the optical position. The flux density is 253 (+/-5) microJy at 10 GHz. The mean observation time is approximately 59972.297, 6.0 days after the first reported optical detection.
The detection of radio emission supports the conclusion that the source is the afterglow of a relativistic explosion at cosmological distance.
We thank the VLA staff for rapidly scheduling and executing these observations.
DisclaimerNone
GCN Circular 33240
Subject
ZTF23aaarlti/AT2023avj: Assy continued optical observations
Date
2023-01-31T17:15:27Z (2 years ago)
From
Alexei Pozanenko at IKI, Moscow <apozanen@iki.rssi.ru>
N. Pankov (HSE, IKI), V. Kim (FAI, Pulkovo Observatory), A. Pozanenko
(IKI), M. Krugov (FAI), S. Belkin (IKI) report on behalf of GRB IKI FuN:
We observed the optical source ZTF23aaarlti/AT2023avj (Wang et al., GCN
33226) with AZT-20 telescope of Assy-Turgen observatory starting on
2023-01-28 (UT) 13:40:30.
We clearly detect the optical source (Wang et al., GCN 33226; Pankov et
al., GCN 33227) which is also detected in radio (Perley et al., GCN
33233) and in X-ray (Ho et al., GCN 33238).
Preliminary photometry of the optical afterglow in a stacked image is
following
Date UT start MJD Exp. Filter OT Err. UL(3sigma)
(mid, days) (s)
2023-01-28 13:40:30 59972.5698 90*60 r'(AB) 23.10 0.15 24.1
The photometry is based on nearby PS1 stars.
GCN Circular 33252
Subject
ZTF23aaarlti/AT2023avj: AMI-LA radio detection
Date
2023-02-02T12:50:02Z (2 years ago)
From
Lauren Rhodes at Oxford <lauren.rhodes@physics.ox.ac.uk>
Lauren Rhodes (Oxford), Itai Sfaradi (HUJI), Joe Bright (Oxford), Rob Fender (Oxford), Assaf Horesh (HUJI), David Green (Cambridge), Paul Scott (Cambridge), David Titterington (Cambridge) report:
We observed the field of the candidate optical afterglow ZTF23aaarlti (AT2023avj)
(Ho et al., GCN 33226) with the Arcminute Microkelvin Imager Large-Array (AMI-LA) at 15.5 GHz beginning at UT 21:46:05.6 on 31-01-2023 for a total of 4 hours. The flux standard 3c286 was used to calibrate the bandpass response and flux scale of the AMI-LA and J0957+5522 was used as an interleaved complex gain calibrator.
We detect an unresolved source at a position consistent with the one reported in GCN 33226 with a (preliminary) flux density of 157+/-14uJy/beam (including both a statistical uncertainty and a 5% absolute flux scale uncertainty). Further observations are planned.
We thank the staff at the Mullard Radio Astronomy Observatory for carrying out these observations and operating the AMI-LA.