Rapidly Evolving Transients in Archival ZTF Public Alerts

• DOI: 10.48550/arxiv.2305.12974
• Publication Date: 2023-01-01
• Authors: Wenxiong Li; I. Arcavi; Ehud Nakar; A. V. Filippenko; Thomas G. Brink; WeiKang Zheng; Marco C. Lam; Ido Keinan; S. Brennan; Noi Shitrit
• Keywords: Transient (computer programming); Kilonova

We search the archival Zwicky Transient Facility public survey for rapidly evolving transient (RET) candidates based on well-defined criteria between 2018 May and 2021 December. The yielded 19 bona-fide RET candidates, corresponding to a discovery rate of $\sim 5.2$ events per year. Even with Galactic latitude cut $20^\circ$, 8 ($\sim 42$%) are Galactic, including one light-curve shape closely resembling that GW170817 kilonova (KN). An additional event is nova in M31. Four out 21$%) confirmed extragalactic RETs (one here first time) origin 6 cannot be determined. did not find any KN, from which we obtain an upper limit volumetric GW170817-like KNe $R \le$ 2400 Gpc$^{-3}$ yr$^{-1}$ (95% confidence). These results can used quantifying contaminants searches alert streams, specifically when searching kilonovae independently gravitational-wave gamma-ray-burst triggers.