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This content will become publicly available on March 10, 2019

Title: The HectoMAP Cluster Survey. II. X-Ray Clusters

Here, we apply a friends-of-friends algorithm to the HectoMAP redshift survey and cross-identify associated X-ray emission in the ROSAT All-Sky Survey data (RASS). The resulting flux-limited catalog of X-ray cluster surveys is complete to a limiting flux of ~3 × 10 –13 erg s –1 cm –2 and includes 15 clusters (7 newly discovered) with redshifts z ≤ 0.4. HectoMAP is a dense survey (~1200 galaxies deg –2) that provides ~50 members (median) in each X-ray cluster. We provide redshifts for the 1036 cluster members. Subaru/Hyper Suprime-Cam imaging covers three of the X-ray systems and confirms that they are impressive clusters. The HectoMAP X-ray clusters have an L X–σ cl scaling relation similar to that of known massive X-ray clusters. The HectoMAP X-ray cluster sample predicts ~12,000 ± 3000 detectable X-ray clusters in RASS to the limiting flux, comparable with previous estimates.
ORCiD logo [1] ;  [2] ;  [2] ; ORCiD logo [1] ;  [3] ; ORCiD logo [4] ; ORCiD logo [5] ;  [6]
  1. Smithsonian Astrophysical Observatory, Cambridge, MA (United States)
  2. Max-Planck-Institut fur extraterrestrische Physik, Garching (Germany)
  3. Univ. di Torino, Torino (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Torino (Italy)
  4. Korea Institute for Advanced Study, Seoul (Republic of Korea)
  5. SLAC National Accelerator Lab., Menlo Park, CA (United States)
  6. Western Washington Univ., Bellingham, WA (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 855; Journal Issue: 2; Journal ID: ISSN 1538-4357
Institute of Physics (IOP)
Research Org:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org:
Country of Publication:
United States
79 ASTRONOMY AND ASTROPHYSICS; cosmology: observations; galaxies: clusters: general; galaxies: clusters: individual (A2198); large-scale structure of universe; X-rays: galaxies: clusters
OSTI Identifier: