Hong-Xin ZHANG (张红欣)
Department of Astronomy
University of Science and Technology of China
Hefei, Anhui 230026, China
Lihua Building, Rm 18-012
hzhang18 at ustc.edu.cn


Research

Formation and Evolution of Galaxies: from Dwarfs to Giants

Galaxies are the lighthouses of the mostly dark Universe, and they span more than six orders of magnitude in luminosities and masses. The formation and evolution of galaxies have been deeply influencing both the visible and invisible (e.g., dark matter) parts of the Universe. The general topic of galaxy formation and evolution is at the forefront of modern astrophysics. Our research touches several aspects of nearby dwarf and giant galaxies, including their stellar structures, kinematics, interstellar medium, and how these properties change in response to interactions between galaxies. We enjoy the practice of learning physical properties of galaxies by synthesizing (aided by models and simulations) multi-wavelength observational data taken from various telescopes. See here for details of our research.

The picture to the right (Image Credit: ESA/Hubble/R.Gendler) shows an optical view of the Andromeda Galaxy (the nearest giant neighbor of the Milky Way) and its dwarf companioons. Besides the "host" Andromeda Galaxy, the most spectacular satellite galaxies visible in the picture are the Compact Elliptical galaxy M32 (slightly to the left of Andromeda's center) and the Dwarf Elliptical galaxy NGC 205 (to the bottom right of the center).

Research Group

Postdocs

  • Zesen Lin 林泽森 (research topics: interstellar gas and dust, star clusters)
  • Graduate Students

  • Guangwen Chen 陈广文 (research topics: galaxy interactions, galaxy disks, compact dwarfs)
  • Lijun Chen 陈李俊 (research topics: compact dwarfs)
  • Bojun Tao 陶柏钧 (research topics: extragalactic star cluster systems)
  • Undergraduate Students

  • Yimeng Tang 唐毅萌 (topics: spectroscopic analysis of galaxies)
  • Qianhui Chen 陈千惠 (topics: imaging analysis of galaxies)
  • Yan Fang 方严 (topics: spectroscopic analysis of interacting galaxies)
  • Ongoing Project

    AVID: Atomic gas in Virgo Interacting Dwarfs

    Highlighted Research

    Our discovery of a gas-rich dwarf merger event was highlighted by the American Astronomical Society Nova (click the picture for more)

    Our study of neutral atomic hydrogen gas and numerical simulations of a dwarf merger was highlighted by Nature Astronomy (click the picture for more)

    Our discovery of a similar mass-metallicity relation of UCDs and nuclei of dwarf elliptical galaxies was highlighted by Nature Astronomy (click the picture for more)

    Worldwide Telescopes used for our Research

    Telescopes working in the optical and near-infrared can collect information about stellar ages, chemical abundances, kinematics and masses; telescopes working in the far-infrared can collect information about the dust obscured stellar populations; telescopes working in the (sub-)mm wavelengths can collect information about properties of cold gas that is nursery of new star formation; telescopes working in the mm to cm wavelengths can collect information about warm-hot gas properties that may be affected by star formation or active galactic nuclei.

    KPNO 4m

    CTIO 4m

    NTT 3.6m

    MMT 6.5m

    Magellan 6.5m

    JCMT 15m

    ALMA

    GMRT

    VLA

    Standing inside NTT

    Selected Recent Publications

  • The Blue Compact Dwarf Galaxy VCC 848 Formed by Dwarf-Dwarf Merging: HI Gas, Star Formation, and Numerical Simulations, H.-X. Zhang, R. Smith, S.-H. Oh, P. Sanjaya et al., 2020, ApJ, 900, 2
  • New Constraints on the Origin of Surface Brightness Profile Breaks of Disk Galaxies from MaNGA, Y. Tang, Q. Chen, H.-X. Zhang^{*}, Z. Lin, G. Chen, Y. Gao, Z. Liang, H. Liu, X. Kong, 2020, ApJ, 897, 79
  • The Most Predictive Physical Properties for the Stellar Population Radial Profiles of Nearby Galaxies, G. Chen, H.-X. Zhang^{*}, X. Kong^{*}, Z. Lin, Z. Liang, X. Chen, Z. Chen, Z. Song, 2020, ApJ, 895, 146
  • The Blue Compact Dwarf Galaxy VCC 848 Formed by Dwarf-Dwarf Merging, H.-X. Zhang, P. Sanjaya, R. Smith, P.-A., Duc, T.H. Puzia et al., 2020, ApJL, 891, L23
  • Stellar Population Properties of Ultracompact Dwarfs in M87: A Mass-Metallicity Correlation Connecting Low-metallicity Globular Clusters and Compact Ellipticals, H.-X. Zhang, T.H. Puzia, E.W. Peng, C. Liu, P. Cote et al., 2018, ApJ, 858, 1
  • A Study of Two Dwarf Irregular Galaxies with Asymmetrical Star Formation Distributions, D.A. Hunter, S. Gallardo, H.-X. Zhang, A. Adamo, D.O. Cook et al., 2018, ApJ, 855, 1
  • Teaching

  • Introduction to Radio Astronomy

  • counter free