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I am an astronomer at University of Massachusetts Amherst. Here you can get a glimpse of my research activtities.

How galaxies get their gas and how much mass, energy, and metals galaxies return to their surroundings are questions central to our understanding of galaxies and the intergalactic medium. Only stars synthesize metals. Yet only about half of the generated elements are found in stars and the interstellar medium. Galaxies are also missing their share of baryonic matter. Understanding the  flows of the matter/energy in and around galaxies, or their "ecosystem'', is the
focus of my research.

A key to the understanding of the matter and energy flows is the study of various high-energy feedback processes in galaxies. I have concentrated on four closely-related aspects of this research topic:
  1. examining various high-energy sources of the interstellar medium (e.g., supernova remnants, superbubbles, and galactic nuclear regions);
  2. characterizing the global structure as well as the physical and chemical states of hot gas in and around galaxies; 
  3. investigating the interplay of the hot gas with other galactic components;
  4. exploring the interaction of galaxies with their environment, particularly the intragroup/cluster media.
I primarily uses infrared, ultraviolet, and X-ray observations to conduct these studies. I also carry out theoretical and computational studies with my students and collaborators.

Brief CV

Research Projects

  • Galactic Nuclear Regions:
  •  Galactic Feedback and Ecosystem of Galaxies:
    • Chandra X-ray Visionary Program (3 Ms) of the 30 Dorado Nebula (co-I)
    • X-ray absorption line spectroscopy of diffuse hot gas, using FUSE and HST far-UV as well as Chandra/XMM-Newton grating spectra.
    • Deep (300 ks) Chandra study and hydrodynamic simulation of the superbubble N11 in the LMC (co-I).
    • Multi-wavelength study of edge-on galaxies (Chandra news-release),, including Chandra/XMM-Newton surveys and "Continuum HAlos in Nearby Galaxies -- an Evla Survey (CHANG-ES)"
      more than 400 hr EVLA observations at 1.4 GHz and 6 GHz in all 4 Stokes and over a variety of array configurations.
    • High-resolution X-ray spectroscopy of nearby galaxies.
    • Hydrodynamic simulations of hot gaseous bulges and halos.
    • Hubble/COS spectroscopic and X-ray studies of the QSO/galaxy cluster pairs (PI and co-I).

Students and Postdocs

Selected recent invited talks