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arXiv · 2303.04767

The Atacama Cosmology Telescope: Systematic Transient Search of 3-Day Maps

Yaqiong Li·Emily Biermann·Sigurd Naess·Simone Aiola·Rui An·Nicholas Battaglia·Tanay Bhandarkar·Erminia Calabrese·Steve K. Choi·Kevin T. Crowley·Mark Devlin·Cody J. Duell·Shannon M. Duff·Jo Dunkley·Rolando Dunner·Patricio A. Gallardo·Yilun Guan·Carlos Hervias-Caimapo·Adam D. Hincks·Johannes Hubmayr·Kevin M. Huffenberger·John P. Hughes·Arthur Kosowsky·Thibaut Louis·Maya Mallaby-Kay·Jeff McMahon·Federico Nati·Michael D. Niemack·John Orlowski-Scherer·Lyman Page·Cristobal Sifon·Maria Salatino·Suzanne T. Staggs·Cristian Vargas·Eve M. Vavagiakis·Yuhan Wang·Edward J. Wollack
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Abstract

We conduct a systematic search for transients in three years of data (2017-2019) from the Atacama Cosmology Telescope (ACT). ACT covers 40 percent of the sky at three bands spanning from 77 GHz to 277 GHz. Analysis of 3-day mean-subtracted sky maps, which were match-filtered for point sources, yielded 29 transients detections. Eight of these transients are due to known asteroids, and three others were previously published. Four of these events occur in areas of with poor noise models and thus we cannot be confident they are real transients. We are left with 14 new transient events occurring at 11 unique locations. All of these events are associated with either rotationally variable stars or cool stars. Ten events have flat or falling spectra indicating radiation from synchrotron emission. One event has a rising spectrum indicating a different engine for the flare.

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Yaqiong Li, Emily Biermann, Sigurd Naess, Simone Aiola, Rui An, Nicholas Battaglia, Tanay Bhandarkar, Erminia Calabrese, Steve K. Choi, Kevin T. Crowley, Mark Devlin, Cody J. Duell, Shannon M. Duff, Jo Dunkley, Rolando Dunner, Patricio A. Gallardo, Yilun Guan, Carlos Hervias-Caimapo, Adam D. Hincks, Johannes Hubmayr, Kevin M. Huffenberger, John P. Hughes, Arthur Kosowsky, Thibaut Louis, Maya Mallaby-Kay, Jeff McMahon, Federico Nati, Michael D. Niemack, John Orlowski-Scherer, Lyman Page, Cristobal Sifon, Maria Salatino, Suzanne T. Staggs, Cristian Vargas, Eve M. Vavagiakis, Yuhan Wang, Edward J. Wollack. 2023-03-08. The Atacama Cosmology Telescope: Systematic Transient Search of 3-Day Maps. https://doi.org/10.3847/1538-4357/ace599

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