Precision kinematic Sunyaev-Zel’dovich measurements across halo mass and redshift with DESI DR2 and ACT DR6. II. Bright galaxy survey and emission-line galaxies

@article{hadzhiyska2026precision,
  title = {{Precision kinematic Sunyaev-Zel’dovich measurements across halo mass and redshift with DESI DR2 and ACT DR6. II. Bright galaxy survey and emission-line galaxies}},
  author = {Boryana Hadzhiyska and Sergio Ferraro and F. J. Qu and B. Ried Guachalla and E. Schaan and J. Aguilar and Steven P. Ahlen and D. Bianchi and D. Brooks and Francisco Javier Castander and E. Chaussidon and T. Claybaugh and A. de la Macorra and Arjun Dey and Biprateep Dey and P. Doel and J. E. Forero-Romero and ENRIQUE GAZTAÑAGA and Satya Gontcho A Gontcho and G. Gutierrez and J. Guy and K. Honscheid and Cullan Howlett and Dragan Huterer A and Mustapha Ishak and R. Joyce and R. Kehoe and Theodore S. Kisner and Anthony Kremin and O. Lahav and Martin Landriau and Laurent Le Guillou and Alexie Leauthaud and Marc Manera and Paul Martini and Aaron Meisner and R. Miquel and S. Nadathur and N. Palanque‐Delabrouille and Will J. Percival and Francisco Prada and Ignasi Pérez-Ràfols and G Rossi and L. Samushia and E. Sanchez and Edward F. Schlafly and David J. Schlegel and Joseph Harry Silber and David Sprayberry and Gregory Tarlé and Benjamin A. Weaver and R. Zhou and H. Zou},
  journal = {Physical review. D/Physical review. D.},
  year = {2026},
  month = jul,
  doi = {10.1103/g381-bz2j},
  url = {https://doi.org/10.1103/g381-bz2j},
  note = {CC BY},
}

TY  - JOUR
TI  - Precision kinematic Sunyaev-Zel’dovich measurements across halo mass and redshift with DESI DR2 and ACT DR6. II. Bright galaxy survey and emission-line galaxies
AU  - Boryana Hadzhiyska
AU  - Sergio Ferraro
AU  - F. J. Qu
AU  - B. Ried Guachalla
AU  - E. Schaan
AU  - J. Aguilar
AU  - Steven P. Ahlen
AU  - D. Bianchi
AU  - D. Brooks
AU  - Francisco Javier Castander
AU  - E. Chaussidon
AU  - T. Claybaugh
AU  - A. de la Macorra
AU  - Arjun Dey
AU  - Biprateep Dey
AU  - P. Doel
AU  - J. E. Forero-Romero
AU  - ENRIQUE GAZTAÑAGA
AU  - Satya Gontcho A Gontcho
AU  - G. Gutierrez
AU  - J. Guy
AU  - K. Honscheid
AU  - Cullan Howlett
AU  - Dragan Huterer A
AU  - Mustapha Ishak
AU  - R. Joyce
AU  - R. Kehoe
AU  - Theodore S. Kisner
AU  - Anthony Kremin
AU  - O. Lahav
AU  - Martin Landriau
AU  - Laurent Le Guillou
AU  - Alexie Leauthaud
AU  - Marc Manera
AU  - Paul Martini
AU  - Aaron Meisner
AU  - R. Miquel
AU  - S. Nadathur
AU  - N. Palanque‐Delabrouille
AU  - Will J. Percival
AU  - Francisco Prada
AU  - Ignasi Pérez-Ràfols
AU  - G Rossi
AU  - L. Samushia
AU  - E. Sanchez
AU  - Edward F. Schlafly
AU  - David J. Schlegel
AU  - Joseph Harry Silber
AU  - David Sprayberry
AU  - Gregory Tarlé
AU  - Benjamin A. Weaver
AU  - R. Zhou
AU  - H. Zou
PY  - 2026
DA  - 2026/07/30
JO  - Physical review. D/Physical review. D.
DO  - 10.1103/g381-bz2j
UR  - https://doi.org/10.1103/g381-bz2j
AB  - We present the first high-significance spectroscopic stacked kinetic Sunyaev-Zel’dovich (kSZ) measurements of circumgalactic gas profiles for both bright galaxy survey (BGS) and emission line galaxy (ELG) tracers, combining DESI Data Release 2 with ACT Data Release 6. Using reconstructed line-of-sight velocities from the DESI galaxies and high-resolution ACT temperature maps, we detect the kSZ signal at high significance, reaching signal-to-noise ratios of up to ∼ 9 for BGS and ∼ 7.5 for ELGs in optimal stellar-mass selections. Together with the Luminous red galaxies (LRGs) measurements presented in Paper I, these constitute the most significant kSZ detections from any spectroscopic survey to date. We perform the analysis in both real and harmonic space, obtaining consistent results. By splitting both tracers into stellar-mass bins, we study the scaling of the kSZ amplitude with galaxy properties. Combining the kSZ measurements with ACT Data Release 6 (DR6) cosmic microwave background lensing maps enables a joint calibration of the galaxy-halo connection and the gas fractions of host halos. For the BGS galaxies, we observe low gas fractions around the virial radius relative to standard expectations, likely attributable to active galactic nuclei (AGN) activity. We find some evidence for higher-mass halos retaining a larger fraction of their baryons, consistent with more efficient feedback in lower-mass systems. For the ELG sample, dominated by blue, star-forming galaxies, we provide the first detection of the gas distribution in ELG host halos. The ELGs appear to exhibit relatively high gas fractions, which points to the possibility of weaker feedback (due to, e.g., low AGN and supernova feedback activity) at their mass scale. Finally, we present generalized Navarro-Frenk-White fits to the harmonic-space measurements, providing a compact parametrization of gas profiles for forward modeling in large-scale structure analyses.
SN  - 2470-0010
SN  - 2470-0029
SN  - 2470-0037
ER  -