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arXiv · 2409.08429

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

Emily K. Biermann·Yaqiong Li·Sigurd Naess·Steve K. Choi·Susan E. Clark·Mark Devlin·Jo Dunkley·P. A. Gallardo·Yilun Guan·Allen Foster·Matthew Hasselfield·Carlos Hervías-Caimapo·Matt Hilton·Adam D. Hincks·Anna Y. Q. Ho·John C. Hood II·Kevin M. Huffenberger·Arthur Kosowsky·Michael D. Niemack·John Orlowski-Scherer·Lyman Page·Bruce Partridge·Maria Salatino·Cristóbal Sifón·Suzanne T. Staggs·Cristian Vargas·Edward J. Wollack
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Abstract

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 detect 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 that may be in tension with current models.

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Emily K. Biermann, Yaqiong Li, Sigurd Naess, Steve K. Choi, Susan E. Clark, Mark Devlin, Jo Dunkley, P. A. Gallardo, Yilun Guan, Allen Foster, Matthew Hasselfield, Carlos Hervías-Caimapo, Matt Hilton, Adam D. Hincks, Anna Y. Q. Ho, John C. Hood II, Kevin M. Huffenberger, Arthur Kosowsky, Michael D. Niemack, John Orlowski-Scherer, Lyman Page, Bruce Partridge, Maria Salatino, Cristóbal Sifón, Suzanne T. Staggs, Cristian Vargas, Edward J. Wollack. 2024-09-12. The Atacama Cosmology Telescope: Systematic Transient Search of Single Observation Maps. https://doi.org/10.3847/1538-4357/adce70

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