The Atacama Cosmology Telescope: Modeling bulk atmospheric motion

Morris, Thomas W., Bustos, Ricardo, Calabrese, Erminia ORCID: https://orcid.org/0000-0003-0837-0068, Choi, Steve K., Duivenvoorden, Adriaan J., Dunkley, Jo, Dünner, Rolando, Gallardo, Patricio A., Hasselfield, Matthew, Hincks, Adam D., Mroczkowski, Tony, Naess, Sigurd, Niemack, Michael D., Page, Lyman, Partridge, Bruce, Salatino, Maria, Staggs, Suzanne, Treu, Jesse, Wollack, Edward J. and Xu, Zhilei 2022. The Atacama Cosmology Telescope: Modeling bulk atmospheric motion. Physical Review D 105 (4) , 042004. 10.1103/PhysRevD.105.042004

Preview

PDF - Accepted Post-Print Version Download (3MB) | Preview

Abstract

Fluctuating atmospheric emission is a dominant source of noise for ground-based millimeter-wave observations of the cosmic microwave background (CMB) temperature anisotropy at angular scales ≳ 0.5 ° . We present a model of the atmosphere as a discrete set of emissive turbulent layers that move with respect to the observer with a horizontal wind velocity. After introducing a statistic derived from the time-lag dependent correlation function for detector pairs in an array, referred to as the pair-lag, we use this model to estimate the aggregate angular motion of the atmosphere derived from time-ordered data from the Atacama Cosmology Telescope (ACT). We find that estimates derived from ACT’s CMB observations alone agree with those derived from satellite weather data that additionally include a height-dependent horizontal wind velocity and water vapor density. We also explore the dependence of the measured atmospheric noise spectrum on the relative angle between the wind velocity and the telescope scan direction. In particular, we find that varying the scan velocity changes the noise spectrum in a predictable way. Computing the pair-lag statistic opens up new avenues for understanding how atmospheric fluctuations impact measurements of the CMB anisotropy.

Item Type:	Article
Date Type:	Publication
Status:	Published
Schools:	Physics and Astronomy
Additional Information:	Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license
ISSN:	24700010
Date of First Compliant Deposit:	21 March 2022
Date of Acceptance:	16 December 2021
Last Modified:	08 May 2023 01:31
URI:	https://orca.cardiff.ac.uk/id/eprint/148524

Citation Data

Cited 3 times in Scopus. View in Scopus. Powered By Scopus® Data

Actions (repository staff only)

Edit Item