AstroNote 2023-149

We report the discovery of the fast optical transient candidate ZTF23aamhlcz/AT2023jrh with the Zwicky Transient Facility (ZTF, Bellm et al. 2019, Graham et al. 2019) at coordinates:

RA = 12:48:09.68 (192.0403175d)
Dec = +27:05:26.28 (27.090632d)

ZTF23aamhlcz was first detected on 2023-05-27 07:05 UT at r = 19.54 +- 0.22 mag (AB). ZTF23aamhlcz faded by about 1.3 magnitudes in 1.92 days in the r-band. The last ZTF upper limit before the first detection was measured on 2023-05-26 07:55 UT in the r-band, which is about 23 hours before the first detection. There is no pre-detection at the transient location in 3,528 images of the field previously acquired by the ZTF survey. ZTF photometry is reported in the following table:

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     MJD       |     mag AB
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60090.32994 | r > 19.7
60091.29559 | r = 19.54 +- 0.22
60093.21881 | r = 20.82 +- 0.18
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Extinction on the line of sight is negligible, with E(B-V)=0.01 mag. The transient is located at high Galactic latitude b=89.3 deg. There is no cataloged source at the transient location in deep Legacy Survey DR10 and Pan-STARRS (Chambers et al., 2016) archival images.

Follow-up observations are encouraged.

ZTF23aamhlcz was discovered by the ''ZTF Realtime Search and Triggering'' project (ZTFReST; Andreoni & Coughlin et al., 2021) within the ZTF Collaboration.

Based on observations obtained with the Samuel Oschin Telescope 48-inch and the 60-inch Telescope at the Palomar Observatory as part of the Zwicky Transient Facility project. ZTF is supported by the National Science Foundation under Grant No. AST-2034437 and a collaboration including Caltech, IPAC, the Weizmann Institute for Science, the Oskar Klein Center at Stockholm University, the University of Maryland, Deutsches Elektronen-Synchrotron and Humboldt University, the TANGO Consortium of Taiwan, the University of Wisconsin at Milwaukee, Trinity College Dublin, Lawrence Livermore National Laboratories, and IN2P3, France. Operations are conducted by COO, IPAC, and UW.