NASA/IPAC EXTRAGALACTIC DATABASE
Date and Time of the Query: 2019-04-20 T16:10:44 PDT
Help | Comment | NED Home

For refcode 2018ApJ...862..172R:
Retrieve 10 NED objects in this reference.
Please click here for ADS abstract

NED Abstract

Copyright by American Astronomical Society. Reproduced by permission
2018ApJ...862..172R HeCS-red: Dense Hectospec Surveys of redMaPPer-selected Clusters Rines, Kenneth J.; Geller, Margaret J.; Diaferio, Antonaldo; Hwang, Ho Seong; Sohn, Jubee Abstract. We use dense redshift surveys to explore the properties of galaxy clusters selected from the redMaPPer catalog. Our new survey, Hectospec Cluster Survey of red-sequence-selected clusters (HeCS-red), includes 10,589 new or remeasured redshifts from MMT/Hectospec observations of 27 redMaPPer clusters at redshifts z = 0.08-0.25 with large estimated richnesses (richness estimate lambda > 64). Our spectra confirm that each candidate cluster corresponds to a large overdensity in redshift space. The redMaPPer photometric redshifts have a slight bias toward higher redshifts. We measure the relation between velocity dispersion sigma_ p_ and lambda. The relation shows intrinsic scatter of 24% (and a range of 2x) in velocity dispersion at fixed richness. We extend our analysis to HeCS-red-ext, a sample that includes several clusters selected by X-ray flux or Sunyaev-Zeldovich signal. The heterogeneous sample of 121 clusters in HeCS-red-ext shows similar intrinsic scatter in the sigma_ p_-lambda relation as the HeCS-red sample, but the range of sigma_ p_ at fixed richness increases to 3x. We evaluate the membership probability estimates P_mem_ for individual galaxies provided by redMaPPer. The spectroscopic membership fraction is larger than P_mem_ for 0.05 <= P_mem_ <= 0.7 conversely, the spectroscopic membership fraction is smaller than P_mem_ at P_mem_ >= 0.8. We compare spectroscopic richness estimates with redMaPPer richness estimates and find good agreement on average, but a range of a factor of two in spectroscopic richness at fixed redMaPPer richness. Overall, within the high-richness and low-redshift cut of our sample, spectroscopically estimated parameters such as velocity dispersion correlate well with photometric richness estimates, although the relations contain substantial scatter. Key words: cosmology: observations, galaxies: clusters: general, galaxies: distances and redshifts, galaxies: kinematics and dynamics
Retrieve 10 NED objects in this reference.
Please click here for ADS abstract

Back to NED Home