Home | Contact | Sitemap | 中文 | CAS
Search:
About Us Research People International Cooperation News Education & Training Join Us Journals Papers Resources Links
Location: Home > News > Seminars
News
  • Events
  • DAMPE
  • Seminars
  • Research Trends
  • Black Holes Grow More Efficiently in Massive Galaxies

     

    Seminar Title  

    Black Holes Grow More Efficiently in Massive Galaxies 
       
    Speaker:   Dr. YANG Guang
       

     Affiliation:    

    ( HUST)  

       
    When Tuesday afternoon , Dec. 20 , 14:00 p.m
       

    Where:   

    Room 416, Office Block, 2 West Beijing Road (PMO, CAS)
     

                             Welcome to Attend   

     
      ( PMO Academic Committee & Academic Circulating committee)
     

       Abstract: The potential coevolution between supermassive black holes (SMBHs) and their host galaxies remains a fundamental problem.In the local universe, the proportionality between SMBH mass and stellar mass of host galaxies provides a strong support for coevolution. Observations of distant star-forming galaxies reveal a tight linear correlation between star formation rate (SFR) and sample-average black-hole accretion rate (BHAR). However, for the host galaxies of X-ray selected AGNs, the SFR is flat as a function of BHAR except at high X-ray luminosities. To reconcile the apparent discrepancy, a recent study advanced a coevolution model assuming that SFR is proportional to long-term average BHAR (average over ~100 Myr), but shorter-term variability has obscured the BHAR-SFR relation.This model is capable in explaining almost all the observational facts so far. We verifythis simple coevolution scenario by studying BHAR dependence on SFR and stellar mass (M_*) of host galaxies. Our study is based on the 7 Ms Chandra Deep Field-South (CDF-S) survey, the deepest X-ray survey, which is available recently. We find that SFR alone is not an adequate tracer of long-term average BHAR. Massive galaxies (M_*>10^10 M_sun) have higher ratios of BHAR/SFR than their less-massive counterparts, indicating that their SMBHs grow more efficiently. 

     

     

    Copyright? Purple Mountain Observatory, CAS, No.10 Yuanhua Road, Qixia District, Nanjing 210023, China
    Phone: 0086 25 8333 2000 Fax: 8333 2091 http://english.pmo.cas.cn