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This content will become publicly available on July 27, 2017

Title: The evolution of the intracluster medium metallicity in Sunyaev Zel'dovich-selected galaxy clusters at 0 < z < 1.5

Here, we present the results of an X-ray spectral analysis of 153 galaxy clusters observed with the Chandra, XMM-Newton, and Suzaku space telescopes. These clusters, which span 0 < z < 1.5, were drawn from a larger, mass-selected sample of galaxy clusters discovered in the 2500 square degree South Pole Telescope Sunyaev Zel'dovich (SPT-SZ) survey. With a total combined exposure time of 9.1 Ms, these data yield the strongest constraints to date on the evolution of the metal content of the intracluster medium (ICM). We find no evidence for strong evolution in the global (r < R 500) ICM metallicity (dZ/dz = –0.06 ± 0.04 Z ⊙), with a mean value at z = 0.6 of $$\langle Z\rangle =0.23\pm 0.01$$ Z ⊙ and a scatter of σ Z = 0.08 ± 0.01 Z ⊙. These results imply that the emission-weighted metallicity has not changed by more than 40% since z = 1 (at 95% confidence), consistent with the picture of an early (z > 1) enrichment. We find, in agreement with previous works, a significantly higher mean value for the metallicity in the centers of cool core clusters versus non-cool core clusters. We find weak evidence for evolution in the central metallicity of cool core clusters (dZ/dz = –0.21 ± 0.11 Z ⊙), which is sufficient to account for this enhanced central metallicity over the past ~10 Gyr. We find no evidence for metallicity evolution outside of the core (dZ/dz = –0.03 ± 0.06 Z ⊙), and no significant difference in the core-excised metallicity between cool core and non-cool core clusters. This suggests that strong radio-mode active galactic nucleus feedback does not significantly alter the distribution of metals at $$r\gt 0.15{R}_{500}$$. Given the limitations of current-generation X-ray telescopes in constraining the ICM metallicity at z > 1, significant improvements on this work will likely require next-generation X-ray missions.
 [1] ;  [1] ;  [2] ;  [1] ;  [3] ;  [4] ;  [5] ;  [6] ;  [7] ;  [8] ;  [9] ;  [10] ;  [11] ;  [11] ;  [12] ;  [7] ;  [13] ;  [8] ;  [14]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States)
  2. Univ. of California, Berkeley, CA (United States)
  3. Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States); Univ. of Chicago, Chicago, IL (United States)
  4. Univ. of Chicago, Chicago, IL (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
  5. Univ. of Missouri, Kansas City, MO (United States)
  6. Univ. of Chicago, Chicago, IL (United States)
  7. Ludwig-Maximilians-Univ., Munich (Germany); Excellence Cluster Universe, Garching (Germany)
  8. Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States)
  9. Univ. de Montreal, Montreal, QC (Canada)
  10. Huntingdon Institute for X-ray Astronomy, LLC, Huntingdon, PA (United States)
  11. Ludwig-Maximilians-Univ., Munich (Germany); Excellence Cluster Universe, Garching (Germany); Max Planck Institute for Extraterrestrial Physics, Garching (Germany)
  12. Univ. of Melbourne, Parkville, VIC (Australia)
  13. Univ. of Hawaii, Honolulu, HI (United States)
  14. Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States)
Publication Date:
OSTI Identifier:
Report Number(s):
FERMILAB-PUB--16-086-A-AE-PPD; arXiv:1603.03035
Journal ID: ISSN 1538-4357; 1426988
Grant/Contract Number:
Accepted Manuscript
Journal Name:
The Astrophysical Journal (Online)
Additional Journal Information:
Journal Name: The Astrophysical Journal (Online); Journal Volume: 826; Journal Issue: 2; Journal ID: ISSN 1538-4357
Institute of Physics (IOP)
Research Org:
Argonne National Laboratory (ANL), Argonne, IL (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States)
Sponsoring Org:
USDOE Office of Science (SC), High Energy Physics (HEP) (SC-25)
Contributing Orgs:
Country of Publication:
United States