A Comprehensive Characterization of Galaxy-cool CGM Connections at <i>z</i> < 0.4 with DESI Year 1 Data
Abstract We investigate the relationships between the cool circumgalactic medium (CGM), traced by Ca ii absorption lines, and galaxy properties at z < 0.4 using ∼900,000 galaxy–quasar pairs within 200 kpc from the Year 1 data of the Dark Energy Spectroscopic Instrument (DESI). This large data set enables us to obtain composite spectra with sensitivity reaching to the mÅ level and to explore the Ca ii absorption as a function of stellar mass, star formation rate (SFR), redshift, and galaxy types, including active galactic nuclei (AGNs). Our results show a positive correlation between the absorption strength and stellar mass of star-forming galaxies with <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mo stretchy="false">〈</mml:mo> <mml:msubsup> <mml:mrow> <mml:mi>W</mml:mi> </mml:mrow> <mml:mrow> <mml:mn>0</mml:mn> </mml:mrow> <mml:mrow> <mml:mrow> <mml:mi mathvariant="normal">Ca</mml:mi> </mml:mrow> <mml:mspace width="0.25em"/> <mml:mrow> <mml:mi mathvariant="normal">II</mml:mi> </mml:mrow> </mml:mrow> </mml:msubsup> <mml:mo stretchy="false">〉</mml:mo> <mml:mo>∝</mml:mo> <mml:msubsup> <mml:mrow> <mml:mi>M</mml:mi> </mml:mrow> <mml:mrow> <mml:mo>∗</mml:mo> </mml:mrow> <mml:mrow> <mml:mn>0.5</mml:mn> </mml:mrow> </mml:msubsup> </mml:math> over 3 orders of magnitude in stellar mass from ∼10 8 to 10 11 M ⊙ , while such a mass dependence is weaker for quiescent galaxies. At a fixed mass, Ca ii absorption is stronger around star-forming galaxies than quiescent ones especially within impact parameters <30 kpc. Among star-forming galaxies, the Ca ii absorption further correlates with SFR, following ∝SFR 0.3 . However, in contrast to the results at higher redshifts, stronger absorption is not preferentially observed along the minor axis of star-forming galaxies, indicating a possible redshift evolution of CGM dynamics resulting from galactic feedback. Moreover, no significant difference between the properties of the cool gas around AGNs and galaxies is detected. Finally, we measure the absorption profiles with respect to the virial radius of dark matter halos and show that the total Ca ii mass in the CGM is comparable to the Ca mass in the ISM of galaxies.
Authors
- Ting-Wen Lan (ORCID: https://orcid.org/0000-0001-8857-7020)
- D. Brooks (ORCID: https://orcid.org/0000-0002-8458-5047)
- Rongpu Zhou (ORCID: https://orcid.org/0000-0001-5381-4372)
- S. Juneau (ORCID: https://orcid.org/0000-0002-0000-2394)
- Michael S. Schubnell (ORCID: https://orcid.org/0000-0001-9504-2059)
- G Rossi
- S. Nadathur (ORCID: https://orcid.org/0000-0001-9070-3102)
- Gregory Tarlé (ORCID: https://orcid.org/0000-0003-1704-0781)
- Jason Xavier Prochaska (ORCID: https://orcid.org/0000-0002-7738-6875)
- Laurent Le Guillou (ORCID: https://orcid.org/0000-0001-7178-8868)
- D. Bianchi (ORCID: https://orcid.org/0000-0001-9712-0006)
- David J. Schlegel (ORCID: https://orcid.org/0000-0002-5042-5088)
- Ignasi Pérez-Ràfols (ORCID: https://orcid.org/0000-0001-6979-0125)
- Axel de la Macorra (ORCID: https://orcid.org/0000-0002-1769-1640)
- Martin Landriau (ORCID: https://orcid.org/0000-0003-1838-8528)
- Simone Ferraro (ORCID: https://orcid.org/0000-0003-4992-7854)
- A. Saintonge (ORCID: https://orcid.org/0000-0003-4357-3450)
- Marc Manera (ORCID: https://orcid.org/0000-0003-4962-8934)
- J. Aguilar (ORCID: https://orcid.org/0000-0003-0822-452X)
- Y. S. Ng (ORCID: https://orcid.org/0009-0006-0529-5460)
- Anthony Kremin (ORCID: https://orcid.org/0000-0001-6356-7424)
- Eusebio Sanchez (ORCID: https://orcid.org/0000-0002-9646-8198)
- Satya Gontcho A Gontcho (ORCID: https://orcid.org/0000-0003-3142-233X)
- ENRIQUE GAZTAÑAGA (ORCID: https://orcid.org/0000-0001-9632-0815)
- K. Honscheid (ORCID: https://orcid.org/0000-0002-6550-2023)
- M. Siudek (ORCID: https://orcid.org/0000-0002-2949-2155)
- Joseph Harry Silber (ORCID: https://orcid.org/0000-0002-3461-0320)
- Arjun T. Dey (ORCID: https://orcid.org/0000-0002-4928-4003)
- G. Gutierrez
- J. E. Forero-Romero (ORCID: https://orcid.org/0000-0002-2890-3725)
- Steven P. Ahlen (ORCID: https://orcid.org/0000-0001-6098-7247)
- Aaron Meisner (ORCID: https://orcid.org/0000-0002-1125-7384)
- R. Miquel (ORCID: https://orcid.org/0000-0002-6610-4836)
- Theodore S. Kisner (ORCID: https://orcid.org/0000-0003-3510-7134)
- Y. L. Chang (ORCID: https://orcid.org/0000-0002-0196-3496)
- John Moustakas (ORCID: https://orcid.org/0000-0002-2733-4559)
- Claire Poppett (ORCID: https://orcid.org/0000-0003-0512-5489)
- Mustapha Ishak (ORCID: https://orcid.org/0000-0002-6024-466X)
- Hee‐Jong Seo (ORCID: https://orcid.org/0000-0002-6588-3508)
- Hu Zou (ORCID: https://orcid.org/0000-0002-6684-3997)
- T. Claybaugh (ORCID: https://orcid.org/0000-0002-5024-6987)
- P. Doel (ORCID: https://orcid.org/0000-0002-6397-4457)
- B. A. Weaver
- Adam D. Myers
Publication Details
- Journal
- The Astrophysical Journal
- Published
- 2025-10-28
- DOI
- https://doi.org/10.3847/1538-4357/ae0613
- Citations
- 1
- Primary Topic
- Galaxies: Formation, Evolution, Phenomena
- Type
- article
- Field-Weighted Citation Impact
- 1.15
Funders
- National Science Foundation
- U.S. Department of Energy
- Gordon and Betty Moore Foundation
- Ministry of Education, India
- Ministerio de Ciencia e Innovación
- National Taiwan University
- Commissariat à l'Énergie Atomique et aux Énergies Alternatives
- National Science and Technology Council
- Office of Science
- Science and Technology Facilities Council
- Division of Astronomical Sciences