Backlighting extended gas halos around luminous red galaxies: Kinematic Sunyaev-Zel’dovich effect from DESI Y1 and ACT data

Journal Article · Fri Nov 07 00:00:00 EST 2025 · Physical Review. D.

DOI:https://doi.org/10.1103/lqbj-wcqj· OSTI ID:3006973

Guachalla, Bernardita Ried ^[1]; Schaan, Emmanuel ^[2]; Hadzhiyska, Boryana ^[3]; Ferraro, Simone ^[4]; Aguilar, Jessica N. ^[5]; Ahlen, Steven ^[6]; Battaglia, Nicholas ^[7]; Bianchi, Davide ^[8]; Bond, Richard ^[9]; Brooks, David ^[10]; Claybaugh, Todd ^[5]; Coulton, William R. ^[11]; de la Macorra, Axel ^[12]; Devlin, Mark J. ^[13]; Dey, Arjun ^[14]; Doel, Peter ^[10]; Dunkley, Jo ^[15]; Fanning, Kevin ^[2]; Forero-Romero, Jaime ^[16]; Gaztañaga, Enrique ^[17] ; Gontcho, Satya Gontcho A. ^[5]; Gutierrez, Gaston ^[18]; Guy, Julien ^[5]; Hill, J. Colin ^[19]; Honscheid, Klaus ^[20]; Juneau, Stephanie ^[14]; Kisner, Theodore ^[5]; Kremin, Anthony ^[5]; Lambert, Andrew ^[5]; Landriau, Martin ^[5]; Le Guillou, Laurent ^[21]; MacCrann, Niall ^[11]; Manera, Marc ^[22]; Meisner, Aaron ^[14]; Miquel, Ramon ^[23]; Moodley, Kavilan ^[24]; Moustakas, John ^[25]; Mroczkowski, Tony ^[26]; Myers, Adam D. ^[27]; Niemack, Michael D. ^[28]; Niz, Gustavo ^[29]; Palanque-Delabrouille, Nathalie ^[30]; Percival, Will ^[31]; Pérez-Ràfols, Ignasi ^[32]; Poppett, Claire ^[3]; Prada, Francisco ^[33]; Qu, Frank J. ^[2]; Rossi, Graziano ^[34]; Sanchez, Eusebio ^[35]; Schlegel, David ^[5]; Schubnell, Michael ^[36]; Seo, Hee-Jong ^[37]; Sifón, Cristóbal ^[38]; Spergel, David N. ^[39]; Sprayberry, David ^[14]; Tarlé, Gregory ^[40]; Vargas-Magaña, Mariana ^[12]; Vavagiakis, Eve M. ^[41]; Weaver, Benjamin A. ^[14]; Wollack, Edward J. ^[42]; Zarrouk, Pauline ^[21]

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1. Stanford University, CA (United States); Kavli Institute for Particle Astrophysics and Cosmology, Stanford, CA (United States); SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); et al.
2. Kavli Institute for Particle Astrophysics and Cosmology; SLAC National Accelerator Laboratory
3. Lawrence Berkeley National Laboratory; University of California; University of California
4. Lawrence Berkeley National Laboratory; University of California
5. Lawrence Berkeley National Laboratory
6. Boston University
7. Cornell University; Université Paris Cité
8. Università degli Studi di Milano
9. University of Toronto
10. University College London
11. Kavli Institute for Cosmology Cambridge; University of Cambridge
12. Ciudad Universitaria
13. University of Pennsylvania
14. NSF NOIRLab
15. Princeton University; Princeton University
16. Universidad de los Andes; Universidad de los Andes
17. Institut d’Estudis Espacials de Catalunya (IEEC); University of Portsmouth; Institute of Space Sciences
18. Fermi National Accelerator Laboratory
19. Columbia University
20. The Ohio State University; The Ohio State University; The Ohio State University
21. Sorbonne Université
22. Universitat Autònoma de Barcelona; Barcelona Institute of Science and Technology
23. Barcelona Institute of Science and Technology; Institució Catalana de Recerca i Estudis Avançats
24. University of KwaZulu-Natal; University of KwaZulu-Natal
25. Siena College
26. European Southern Observatory (ESO)
27. University of Wyoming
28. Cornell University; Cornell University
29. Universidad de Guanajuato; Instituto Avanzado de Cosmología A. C.
30. Lawrence Berkeley National Laboratory; Université Paris-Saclay
31. University of Waterloo; Perimeter Institute for Theoretical Physics; University of Waterloo
32. Universitat Politècnica de Catalunya
33. Glorieta de la Astronomía
34. Sejong University
35. CIEMAT
36. University of Michigan; University of Michigan
37. Ohio University
38. Pontificia Universidad Católica de Valparaíso
39. Flatiron Institute
40. University of Michigan
41. Cornell University; Duke University
42. NASA Goddard Space Flight Center

The gas density profile around galaxies, shaped by feedback and affecting the galaxy lensing signal, is imprinted on the cosmic microwave background (CMB) by the kinematic Sunyaev-Zel’dovich effect (kSZ). We precisely measure this effect (𝑆/𝑁 ≈ 10) via velocity stacking with 825,283 spectroscopically confirmed luminous red galaxies (LRG) from the Dark Energy Spectroscopic Instrument Year 1 (DESI Y1) survey, which overlap with the Atacama Cosmology Telescope (ACT) Data Release 6 temperature maps over ≥ 4,000  deg². We explore the kSZ dependence with various galaxy parameters and find no significant trend with redshift but clear trends with stellar mass and absolute magnitude in 𝑔, 𝑟, and 𝑧 bands. Our analysis suggests that the gas extends beyond the dark matter halo (99.5% confidence level, i.e., probability to exceed (PTE)⁢ = 0.005). We find a tentative preference for hydrodynamical simulation models with stronger feedback that drives gas further out (Illustris 𝑧 = 0.5, PTE⁢ = 0.37) over weaker-feedback cases (IllustrisTNG 𝑧 = 0.8, PTE⁢ = 0.045), though with limited statistical significance. In all cases, a free multiplicative amplitude was fit to the simulated profiles, and further modeling work is required to firm up these conclusions. We find consistency between kSZ profiles around spectroscopic and photometric LRG, with comparable statistical power, thus increasing our confidence in the photometric analysis. Additionally, we present the first kSZ measurement around the DESI Y1 bright galaxy sample (BGS) and the emission-line galaxies (ELG) whose features match qualitative expectations. Finally, we forecast 𝑆/𝑁 ∼ 50 for future stacked kSZ measurements using data from the ACT, the DESI Y3, and the Rubin Observatory. Furthermore, these measurements will serve as an input for galaxy formation models and baryonic uncertainties in galaxy lensing.

• Research Organization: APC, Paris; Andes U., Bogota; Barcelona, Autonoma U.; Barcelona, IEEC; Barcelona, IFAE; Barcelona, Polytechnic U.; Boston U.; CCA, New York; Cambridge U., DAMTP; Cambridge U., Inst. of Astron.; Canadian Inst. Theor. Astrophys.; Chicago U., KICP; Columbia U.; Columbia U., Astron. Astrophys.; Cornell U.; Duke U.; European Southern Observ.; Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Granada U., Theor. Phys. Astrophys.; Guanajuato U.; Hiroshima Shudo U.; ICE, Bellaterra; ICREA, Barcelona; IRFU, Saclay; KEK, Tsukuba; KwaZulu Natal U.; LPNHE, Paris; Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Madrid, CIEMAT; Mexico U., ICN; Michigan U.; Milan U.; NASA, Goddard; Natl. Solar Observ., Tucson; Ohio State U.; Ohio U., Athens; Pennsylvania U.; Perimeter Inst. Theor. Phys.; Portsmouth U., ICG; Princeton U.; Princeton U., Astrophys. Sci. Dept.; SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Sejong U.; Siena Coll., Loudonville; Stanford U.; Stanford U., ITP; UC, Berkeley; UC, Berkeley, Math. Dept.; UC, Berkeley, Space Sci. Dept.; UNAM, Mexico; University Coll. London; University of Michigan, Ann Arbor, MI (United States); Valparaiso U., Catolica; Waterloo U.; Wyoming U.
• Sponsoring Organization: National Aeronautics and Space Administration (NASA); U.S. National Science Foundation; US Department of Energy; USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: 89243024CSC000002; AC02-05CH11231; AC02-76SF00515; SC0019193
• OSTI ID: 3006973
• Alternate ID(s): OSTI ID: 2549333
• Report Number(s): FERMILAB-PUB-25-0196-PPD
• Journal Information: Physical Review. D., Journal Name: Physical Review. D. Journal Issue: 10 Vol. 112; ISSN 2470-0010; ISSN 2470-0029
• Publisher: American Physical Society (APS)
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
Cosmic microwave background
Cosmology
Formation & evolution of stars & galaxies
Large scale structure of the Universe
Optical
UV
& IR astronomy
Radio
microwave
& sub-mm astronomy