학술논문
The Atacama Cosmology Telescope: Flux Upper Limits from a Targeted Search for Extragalactic Transients
Document Type
Working Paper
Author
Hervías-Caimapo, Carlos; Naess, Sigurd; Hincks, Adam D.; Calabrese, Erminia; Devlin, Mark J.; Dunkley, Jo; Dünner, Rolando; Gallardo, Patricio A.; Hilton, Matt; Huffenberger, Anna Y. Q. Ho Kevin M.; Ma, Xiaoyi; Madhavacheril, Mathew S.; Niemack, Michael D.; Orlowski-Scherer, John; Page, Lyman A.; Partridge, Bruce; Puddu, Roberto; Salatino, Maria; Sifón, Cristóbal; Staggs, Suzanne T.; Vargas, Cristian; Vavagiakis, Eve M.; Wollack, Edward J.
Source
Subject
Language
Abstract
We have performed targeted searches of known extragalactic transient events at millimetre wavelengths using nine seasons (2013--2021) of 98, 150, and 229\,GHz Atacama Cosmology Telescope (ACT) observations that mapped ${\sim}40$ per cent of the sky for most of the data volume. Our data cover 88 gamma-ray bursts (GRBs), 12 tidal disruption events (TDEs) and 203 other transients, including supernovae (SNe). We stack our ACT observations to increase the signal-to-noise ratio of the maps. In all cases but one, we do not detect these transients in the ACT data. The single candidate detection (event AT2019ppm), seen at ${\sim}5\sigma$ significance in our data, appears to be due to active galactic nuclei (AGN) activity in the host galaxy coincident with a transient alert. For each source in our search we provide flux upper limits. For example, the medians for the 95 per cent confidence upper limits at 98\,GHz are $15$, $18$, and $16$\,mJy for GRBs, SNe, and TDEs respectively, in the first month after discovery. The projected sensitivity of future wide-area cosmic microwave background (CMB) surveys should be sufficient to detect many of these events using the methods described in this paper.
Comment: 14 pages, 7 figures, 8 tables. The full tables of flux upper limits for individual transients are available at https://lambda.gsfc.nasa.gov/product/act/actadv_targeted_transient_constraints_2023_info.html. Accepted for publication by MNRAS
Comment: 14 pages, 7 figures, 8 tables. The full tables of flux upper limits for individual transients are available at https://lambda.gsfc.nasa.gov/product/act/actadv_targeted_transient_constraints_2023_info.html. Accepted for publication by MNRAS