The Atacama Cosmology Telescope: Systematic Transient Search of Single Observation Maps

• DOI: 10.48550/arxiv.2409.08429
• Publication Date: 2024-01-01
• Authors: Biermann, Emily K.; Li, Yaqiong; Naess, Sigurd; Choi, Steve K.; Clark, Susan E.; Devlin, Mark; Dunkley, Jo; Gallardo, P. A.; Guan, Yilun; Foster, Allen; Hasselfield, Matthew; Hervías-Caimapo, ...; Hilton, Matt; Hincks, Adam D.; Ho, Anna Y. Q.; Hood II, John C.; Huffenberger, Kev...; Kosowsky, Arthur; Niemack, Michael D.; Orlowski-Scherer,...; Page, Lyman; Partridge, Bruce; Salatino, Maria; Sifón, Cristóbal; Staggs, Suzanne T.; Vargas, Cristian; Wollack, Edward J.
• Keywords: High Energy Astrophysical Phenomena (astro-ph.HE); Astrophysics - Solar and Stellar Astrophysics; Astrophysics of Galaxies (astro-ph.GA); FOS: Physical sciences; Astrophysics - High Energy Astrophysical Phenomena; Astrophysics - Instrumentation and Methods for Astrophysics; Astrophysics - Astrophysics of Galaxies; Instrumentation and Methods for Astrophysics (astro-ph.IM); Solar and Stellar Astrophysics (astro-ph.SR)

We conduct a systematic search for astrophysical transients using data from the Atacama Cosmology Telescope (ACT). The data were taken from 2017 to 2022 in three frequency bands spanning 77 GHz to 277 GHz. In this paper we present a pipeline for transient detection using single observation maps where each pixel of a map contains one observation with an integration time of approximately four minutes. We find 34 transient events at 27 unique locations. All but two of the transients are associated with Galactic stars and exhibit a wide range of properties. We also detect an event coincident with the classical nova, YZ Ret and one event consistent with a flaring active galactic nucleus. We notably do not detect any reverse shock emission from gamma ray bursts, a non-detection which is in tension with current models.<br/>23 pages, 10 figures, 10 tables. First and second author share equal contributions. Article and accompanying data submitted to ApJ. Data tables will be made available upon publication<br/>