The Effect of Splashback on Weak Lensing Mass Estimates of Galaxy Clusters and Groups

Journal Article · Thu May 25 00:00:00 EDT 2023 · The Open Journal of Astrophysics

DOI:https://doi.org/10.21105/astro.2212.05406· OSTI ID:1909882

Zhang, Yuanyuan  ^[1]; Adhikari, Susmita ^[2]; Constanzi, Matteo ^[3]; Frieman, Josh ^[4]; Annis, Jim ^[5]; Chang, Chihway ^[6]

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1. National Optical-Infrared Astronomy Research Laboratory, Tucson, AZ (United States); Texas A & M University, College Station, TX (United States)
2. Indian Institute of Science Education and Research, Pune (India)
3. University of Trieste (Italy); Istituto Nazionale di Astrofisica, Trieste (Italy). Osservatorio Astronomico di Trieste; Institute for Fundamental Physics of the Universe, Trieste (Italy)
4. University of Chicago, IL (United States). Kavli Inst. for Cosmological Physics (KICP); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
5. Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
6. University of Chicago, IL (United States). Kavli Inst. for Cosmological Physics (KICP)

The splashback radius of a dark matter halo, which corresponds to the first apocenter radius reached by infalling matter and substructures, has been detected around galaxy clusters using a multitude of observational methods, including weak lensing measurements. In this manuscript, we present how the splashback feature in the halo density profile affects galaxy cluster masses derived through weak lensing measurements if it is not accounted for. We find that the splashback radius has an increasingly large effect on group-sized halos towards $$M_{200m} \sim 10^{13.5} \mathrm{M_\odot}$$. Depending on the model and the radial scale used, the cluster/group masses can be biased low by more than 0.1 dex. This bias, in turn, would result in a slightly lower $$\Omega_m$$ value if propagated into a cluster cosmology analysis. The splashback effect with group-sized dark matter halos may become important to consider, given the increasingly stringent cosmological constraints coming from optical wide-field surveys.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP)
• Grant/Contract Number: AC02-07CH11359
• OSTI ID: 1909882
• Report Number(s): FERMILAB-PUB-22-966-PPD; arXiv:2212.05406; oai:inspirehep.net:2613407; TRN: US2312183
• Journal Information: The Open Journal of Astrophysics, Vol. 6; ISSN 2565-6120
• Publisher: Maynooth Academic Publishing
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS