MacCrann, Niall, Qu, Frank J., Namikawa, Toshiya, Bolliet, Boris, Cai, Hongbo, Calabrese, Erminia  ORCID: https://orcid.org/0000-0003-0837-0068, Choi, Steve K., Coulton, William, Darwish, Omar, Ferraro, Simone, Guan, Yilun, Hill, J.Colin, Hilton, Matt, Hlo?ek, Renée, Kramer, Darby, Madhavacheril, Mathew S., Moodley, Kavilan, Sehgal, Neelima, Sherwin, Blake D., Sifón, Cristóbal, Staggs, Suzanne T., Trac, Hy, Van Engelen, Alexander and Vavagiakis, Eve M.
2024.
The Atacama Cosmology Telescope: reionization kSZ trispectrum methodology and limits.
Monthly Notices of the Royal Astronomical Society
532
(4)
, pp. 4247-4260.
10.1093/mnras/stae1746
|
Preview |
PDF
- Published Version
Available under License Creative Commons Attribution. Download (7MB) | Preview |
Abstract
Patchy reionization generates kinematic Sunyaev–Zel’dovich (kSZ) anisotropies in the cosmic microwave background (CMB). Large-scale velocity perturbations along the line of sight modulate the small-scale kSZ power spectrum, leading to a trispectrum (or four-point function) in the CMB that depends on the physics of reionization. We investigate the challenges in detecting this trispectrum and use tools developed for CMB lensing, such as realization-dependent bias subtraction and cross-correlation based estimators, to counter uncertainties in the instrumental noise and assumed CMB power spectrum. We also find that both lensing and extragalactic foregrounds can impart larger trispectrum contributions than the reionization kSZ signal. We present a range of mitigation methods for both of these sources of contamination, validated on microwave-sky simulations. We use ACT DR6 and Planck data to calculate an upper limit on the reionization kSZ trispectrum from a measurement dominated by foregrounds. The upper limit is about 50 times the signal predicted from recent simulations.
| Item Type: | Article |
|---|---|
| Date Type: | Published Online |
| Status: | Published |
| Schools: | Physics and Astronomy |
| Publisher: | Oxford University Press |
| ISSN: | 0035-8711 |
| Date of First Compliant Deposit: | 11 September 2024 |
| Date of Acceptance: | 11 July 2024 |
| Last Modified: | 13 Sep 2024 14:13 |
| URI: | https://orca.cardiff.ac.uk/id/eprint/172008 |
Actions (repository staff only)
 |
Edit Item |
Altmetric
Altmetric
Cardiff University Information Services