IPAC

Home

NASA/IPAC Extragalactic Database

  • Home
  • Search Objects
    • By Name
    • Near Name or Position (Cone)
    • In Refcode
    • By Parameters
  • Literature
    • References by Author Name
    • Reference Lookup
    • Nomenclature
  • Services
    • Gravitational Wave Followup
      • Overview
      • Events
    • Ticket Status
    • Level5
      • Knowledge Base
      • Glossary
    • Classic Home Page
  • Tools
    • Coordinate Calculator
    • Extinction Calculator
    • Velocity Calculator
  • Information
    • Overview
      • News
      • Archived Release Notes
    • User Guides
      • Search Objects
      • Calculators
      • Program Interfaces
      • Database
      • Tutorials
      • Best Practices
      • Search & Retrieval FAQ
      • Scientific Calculations FAQ
      • Known Issues
      • Discontinuing Services
    • Holdings
      • Nomenclature
      • Counts
      • Graphics
      • Data Sets
    • References
      • Articles about NED
      • Brochure (pdf)
      • Cosmology Calculators
      • Extinction-Law Calculators
      • Related Sites
    • Community
      • Users Committee
      • Ambassadors
    • Team
    • Contact Us

You are here

Home » Literature » Reference Lookup

Help Reference Information

TitleHeCS-SZ: The Hectospec Survey of Sunyaev-Zeldovich-selected Clusters
AuthorsRines, Kenneth J.; Geller, Margaret J.; Diaferio, Antonaldo; Hwang, Ho Seong
Bibcode

2016ApJ...819...63R   Search ADS ↗

AbstractWe estimate cluster masses and velocity dispersions for 123 clusters from optical spectroscopy to compare the Sunyaev-Zeldovich (SZ) mass proxy and dynamical masses. Our new survey, HeCS-SZ (Hectospec Cluster Survey of SZ-selected clusters), includes 7721 new or remeasured redshifts from MMT/Hectospec observations of 21 SZ-selected clusters at redshifts z = 0.05-0.20. We supplement the Hectospec data with spectra from the Sloan Digital Sky Survey (SDSS) and cluster data from the Cluster Infall Regions in SDSS project and the Hectospec Cluster Survey, our Hectospec survey of clusters selected by X-ray flux. We measure the scaling relation between velocity dispersion and SZ mass estimates from the integrated Compton parameter for an SZ-complete sample of 83 clusters. The observed relation agrees very well with a simple virial scaling from mass (based on SZ) to velocity dispersion. The SZ mass estimates (calibrated with hydrostatic X-ray mass estimates) are not significantly biased compared to dynamical mass estimates under the assumption of small velocity bias of galaxies compared to dark matter particles. Significant mass bias in SZ mass estimates could relieve tension between cosmological results from Planck SZ cluster counts and Planck CMB data. In principle, SZ mass bias and velocity bias of galaxies could conspire to yield good agreement, but the required velocity bias is {σ }{galaxy}≈ 0.77{σ }{DM}, outside the range of recent models of velocity bias in the literature. More likely, SZ mass bias and velocity bias are both small, and the tension between SZ cluster counts and CMB data requires another explanation.
Objects

19452 Objects    Search NED ↙

Reload form

The NASA/IPAC Extragalactic Database (NED) is funded by the
National Aeronautics and Space Administration under
Award Number 80NSSC21M0037, and operated by the California Institute of Technology.

  • IPAC
  • Caltech
  • NASA
  • About NED
  • Acknowledging NED
  • Connect with NED:
    • EMail
    • facebook
    • youtube
Copyright © 2025, California Institute of Technology
back up ↑