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Main Authors:	Clancy, Justin, Bacciagalupi, Carlo, Borrow, Josh, Dachlythra, Nadia, Foster, Allen M., Guan, Yilun, Hervias-Caimapo, Carlos, Hincks, Adam D., Hlozek, Renee, Hornecker, Erika, Huffenberger, Kevin M., Nerval, Simran K., Orlowski-Scherer, John, Peel, Mike W., Reichardt, Christian L., Vargas, Cristian
Format:	Preprint
Published:	2025
Subjects:	Instrumentation and Methods for Astrophysics
Online Access:	https://arxiv.org/abs/2512.11313
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author	Clancy, Justin Bacciagalupi, Carlo Borrow, Josh Dachlythra, Nadia Foster, Allen M. Guan, Yilun Hervias-Caimapo, Carlos Hincks, Adam D. Hlozek, Renee Hornecker, Erika Huffenberger, Kevin M. Nerval, Simran K. Orlowski-Scherer, John Peel, Mike W. Reichardt, Christian L. Vargas, Cristian
author_facet	Clancy, Justin Bacciagalupi, Carlo Borrow, Josh Dachlythra, Nadia Foster, Allen M. Guan, Yilun Hervias-Caimapo, Carlos Hincks, Adam D. Hlozek, Renee Hornecker, Erika Huffenberger, Kevin M. Nerval, Simran K. Orlowski-Scherer, John Peel, Mike W. Reichardt, Christian L. Vargas, Cristian
contents	We introduce a method for detecting astrophysical transients evolving on timescales of milliseconds to minutes using cosmic microwave background (CMB) survey telescopes. While previous transient searches in CMB data operate in map space, our pipeline directly processes the raw time-ordered data, enabling sensitivity to fast, dynamic signals. We integrate our detection approach into the Simons Observatory time-domain pipeline and assess the performance on simulated observations with injected stellar flare-like light curves. For events flaring with a timescale of 0.5 s, the pipeline detects $\gtrsim90$% of events at flux densities of 800, 1150, 1650, and 4250 mJy when measured in the 93, 145, 225, and 280 GHz bands respectively. For longer $\ge5$ second flares, the 90% detection thresholds are reduced by a factor of four. We are able to determine the position of detected events in each observing band, with a positional uncertainty at the detection threshold comparable to the telescope resolution at that band. These results demonstrate the readiness of this pipeline for incorporation into upcoming Simons Observatory data analyses.
format	Preprint
id	arxiv_https___arxiv_org_abs_2512_11313
institution	arXiv
publishDate	2025
record_format	arxiv
spellingShingle	The Simons Observatory: Development of a Pipeline to Detect Rapid Transients in Time-Ordered Data Clancy, Justin Bacciagalupi, Carlo Borrow, Josh Dachlythra, Nadia Foster, Allen M. Guan, Yilun Hervias-Caimapo, Carlos Hincks, Adam D. Hlozek, Renee Hornecker, Erika Huffenberger, Kevin M. Nerval, Simran K. Orlowski-Scherer, John Peel, Mike W. Reichardt, Christian L. Vargas, Cristian Instrumentation and Methods for Astrophysics We introduce a method for detecting astrophysical transients evolving on timescales of milliseconds to minutes using cosmic microwave background (CMB) survey telescopes. While previous transient searches in CMB data operate in map space, our pipeline directly processes the raw time-ordered data, enabling sensitivity to fast, dynamic signals. We integrate our detection approach into the Simons Observatory time-domain pipeline and assess the performance on simulated observations with injected stellar flare-like light curves. For events flaring with a timescale of 0.5 s, the pipeline detects $\gtrsim90$% of events at flux densities of 800, 1150, 1650, and 4250 mJy when measured in the 93, 145, 225, and 280 GHz bands respectively. For longer $\ge5$ second flares, the 90% detection thresholds are reduced by a factor of four. We are able to determine the position of detected events in each observing band, with a positional uncertainty at the detection threshold comparable to the telescope resolution at that band. These results demonstrate the readiness of this pipeline for incorporation into upcoming Simons Observatory data analyses.
title	The Simons Observatory: Development of a Pipeline to Detect Rapid Transients in Time-Ordered Data
topic	Instrumentation and Methods for Astrophysics
url	https://arxiv.org/abs/2512.11313

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