Welcome to Prof. Sukyoung K. Yi's group (GEM) homepage

이석영 교수의 은하진화 연구 그룹 홈페이지에 오신것을 환영합니다.

The ultimate goal of our group is to understand the formation and evolution of galaxies. We work on various versions of galaxy formation theories, focusing on dynamical clustering of galaxies and galactic chemical evolution in combination with stellar population synthesis. We extensively, but not exclusively, use SDSS and GALEX data to test our theoretical models.

  • Dr. Scott Croom, Dr. Julia Bryant and Dr. Warrick Couch will visit GEM (10-13 Apr 2017)
  • Dr. Barbara Cantinella and Dr. Luca Cortese at ICRAR are visiting GEM (1-15 Apr 2017)
  • SAMI workshop will be held at KASI. (12 Apr 2017)
  • Environment workshop wiil be held. (3 Apr 2017)
  • Dr. Kang Xi and Dr. Emanuel Contini from the Purple Mountain Observatory (PMO) will visit GEM (9-13 May 2016) (See the poster)
  • Prof. Christophe Pichon at IAP and his group members visited GEM (12 Feb 2016)
  • Dr. Sanjaya Paudel visited GEM (22 Jan 2016)
  • GEM group members participated in the 227th AAS meeting in Florida giving presentations (05-09 Jan 2016)
  • The former GEMer Kyuseok Oh has been awarded "A best thesis at Yonsei". Congratulations to Dr. Oh! (Nov 2015)
  • Honggeun Khim has been awarded "The Jung Sung Ki Alumnus award" for excellent research performance. Congratulations to Khim! (Nov 2015)

  • Title: Constraints on the Evolution of the Galaxy Stellar Mass Function. II. The Quenching Timescale of Galaxies and Its Implication for Their Star Formation Rates

    We study the connection between the observed star formation rate-stellar mass (SFR-M* relation and the evolution of the stellar mass function (SMF) by means of a subhalo abundance matching technique coupled to merger trees extracted from a N-body simulation. Our approach consist of forcing the model to match the observed SMF at redshift z~2.3, and let it evolve down to z~0.3 according to a τ model, an exponentially declining functional form which describes the star formation rate decay of both satellite and central galaxies. Our modelling of quenching timescales is consistent with the evolution of the SMF down to z~0.3, with mean residuals below 0.1 dex in the range ~[108.7-1011.7] M. We then compare the SFR-M* relation predicted by the model with the observed one at different redshifts. The predicted SFR-M* relation underpredicts the median SFR at fixed stellar mass relative to observations at all redshifts. Nevertheless, the shapes are consistent with the observed relations up to intermediate-mass galaxies, followed by a rapid decline for massive galaxies.
    Full text [ADS]

    Last modified: 2018-01-04
       Since 25 March 2010
    Dept. of Astronomy, Yonsei University
    134 shinchon-dong, Sudaemun-gu, Seoul 120-179 Korea
    Copyright 2006 Galaxy Evolution Meeting. Maintained by J. Park