Optical Depths from the Thermal Sunyaev-Zel'dovich Effect with ACT DR6 and DESI DR1 Spectroscopic Galaxies and Optically-Selected Clusters

@misc{moore2026optical,
  title = {{Optical Depths from the Thermal Sunyaev-Zel'dovich Effect with ACT DR6 and DESI DR1 Spectroscopic Galaxies and Optically-Selected Clusters}},
  author = {J.E Moore and C Popik and Y Gong and Y-H Hsu and E.M Vavagiakis and N Battaglia and R Bean and D Gruen and P Gallardo and B Hadzhiyska and G Ockert and J Aguilar and S Ahlen and A Aviles and F Beutler and D Bianchi and J.R Bond and D Brooks and E Bulbul and A Carnero Rosell and E Chaussidon and T Claybaugh and J Comparat and A de la Macorra and Biprateep Dey and P Doel and S Ferraro and A Font-Ribera and J.E Forero-Romero and E Gaztañaga and Satya Gontcho A. Gontcho and G Gutierrez and K Honscheid and M Ishak and S Juneau and T Karim and R Kehoe and M Kluge and A Kremin and A Kusiak and O Lahav and M Landriau and L Le Guillou and M Manera and A Meisner and R Miquel and T Mroczkowski and S Nadathur and J.A Newman and M.D Niemack and H.E Noriega and E Paillas and W.J Percival and F Prada and I Pérez-Ràfols and C Ravoux and B Ried Guachalla and G Rossi and R Ruggeri and L Samushia},
  howpublished = {HAL},
  year = {2026},
  month = sep,
  doi = {10.48550/arxiv.2609.08939},
  eprint = {2609.08939},
  archivePrefix = {arXiv},
  url = {https://hal.science/hal-05758209v1},
}

TY  - UNPB
TI  - Optical Depths from the Thermal Sunyaev-Zel'dovich Effect with ACT DR6 and DESI DR1 Spectroscopic Galaxies and Optically-Selected Clusters
AU  - J.E Moore
AU  - C Popik
AU  - Y Gong
AU  - Y-H Hsu
AU  - E.M Vavagiakis
AU  - N Battaglia
AU  - R Bean
AU  - D Gruen
AU  - P Gallardo
AU  - B Hadzhiyska
AU  - G Ockert
AU  - J Aguilar
AU  - S Ahlen
AU  - A Aviles
AU  - F Beutler
AU  - D Bianchi
AU  - J.R Bond
AU  - D Brooks
AU  - E Bulbul
AU  - A Carnero Rosell
AU  - E Chaussidon
AU  - T Claybaugh
AU  - J Comparat
AU  - A de la Macorra
AU  - Biprateep Dey
AU  - P Doel
AU  - S Ferraro
AU  - A Font-Ribera
AU  - J.E Forero-Romero
AU  - E Gaztañaga
AU  - Satya Gontcho A. Gontcho
AU  - G Gutierrez
AU  - K Honscheid
AU  - M Ishak
AU  - S Juneau
AU  - T Karim
AU  - R Kehoe
AU  - M Kluge
AU  - A Kremin
AU  - A Kusiak
AU  - O Lahav
AU  - M Landriau
AU  - L Le Guillou
AU  - M Manera
AU  - A Meisner
AU  - R Miquel
AU  - T Mroczkowski
AU  - S Nadathur
AU  - J.A Newman
AU  - M.D Niemack
AU  - H.E Noriega
AU  - E Paillas
AU  - W.J Percival
AU  - F Prada
AU  - I Pérez-Ràfols
AU  - C Ravoux
AU  - B Ried Guachalla
AU  - G Rossi
AU  - R Ruggeri
AU  - L Samushia
PY  - 2026
DA  - 2026/09/22
PB  - HAL
DO  - 10.48550/arxiv.2609.08939
UR  - https://hal.science/hal-05758209v1
AB  - We present stacked thermal Sunyaev-Zel'dovich (tSZ) effect measurements for three samples of galaxy groups and clusters: those traced by the Dark Energy Spectroscopic Instrument Data Release 1 (DESI DR1) luminous red galaxies (LRG) and the DESI DR1 Bright Galaxy Sample (BGS), and an eROMaPPer optically-selected sample from the DESI Legacy Imaging Survey. We use the latest Atacama Cosmology Telescope DR6 (ACT)+Planck component-separated internal linear combination (ILC) Compton-y maps and ACT+Planck coadded 90, 150, and 220 GHz temperature maps to extract the tSZ signal within a ∼2' disk aperture for sources binned by luminosity, richness, or mass. We measure the average tSZ signal with high statistical significance, with signal-to-noise ratios surpassing 38 for LRG, 27 for BGS, and 39 for the eROMaPPer sample using the 90 GHz ACT DR6+Planck map. We conduct a detailed study of systematics and foregrounds such as dust and cosmic infrared background (CIB) contamination, which remain a core challenge for tSZ analysis. For the LRG and BGS samples, we find that dust and radio source emission dominate the tSZ signal at scales near and below the disk aperture radius. Large-scale (R>4') contamination from the CIB is less significant. We mitigate these contaminants to isolate the tSZ signal and use a combination of simulated and real measurements to develop Compton-y−optical depth (y̅−τ̅) scaling relations to infer optical depths, which are found to be in agreement with values measured using the pairwise kinematic SZ effect for the same tracer samples. The y̅−τ̅ scaling relation for the eROMaPPer sample is the first such relationship to be derived directly from SZ measurements.
ER  -