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:
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.
- examining various high-energy sources of the
interstellar medium (e.g., supernova remnants, superbubbles, and
galactic nuclear regions);
- characterizing the global structure as well as the
physical and chemical states of hot gas in and around galaxies;
- investigating the interplay of the hot gas with other
- exploring the interaction of galaxies with their
environment, particularly the intragroup/cluster media.
- Galactic Nuclear Regions:
- Galactic Feedback and Ecosystem of Galaxies:
- Chandra X-ray Visionary Program (3 Ms) of the 30 Dorado
- 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 of the superbubble N11 in the LMC (co-I).
- Multi-wavelength study of edge-on galaxies (Chandra
news-release),, including Chandra/XMM-Newton
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.
- Hubble/COS spectroscopic and X-ray studies of the
QSO/galaxy cluster pairs (PI and co-I).
Students and Postdocs
Selected recent invited
Ecosystems, Institute of Astronomy, Cambridge University,
of the X-ray Emission from Sgr A*, Mullard Space Science
Laboratory, University College London, UK, 2013
the Galactic Ecosystem in the IAU Symposium 296, "Supernova
Environmental Impacts", Raichak, India, 2013
and spectroscopy of the hot CGM in local galaxies in the
workshop on “Dynamic Baryons in Halos”, Leiden, Netherlands, 2012
- Sources of X-ray Emission
from Galaxies in
Preston, UK, 2011
- X-ray Spectroscopy of Hot
Plasma in and around Galaxies, Astrophysics Science Division,
Space Flight Center, 2011
Neighborhood and Laboratory Astrophysics, in the 2010
NASA Laboratory Astrophysics Workshop, Gatlinburg, Tennessee
- Living alongside
Monsters: Stellar and Interstellar Matter around
SMBHs in the ISM2010 workshop, Beijing Kavli
Institute for Astronomy
- X-raying the Global Hot
Interstellar and Circum-galactic Media in the
High-Resolution X-Ray Spectroscopy: Past, Present, and Future, 2010,
- Confronting feedback simulations
with observations of hot gas in elliptical galaxies
in the XXVIIth IAU General Assembly, JD8, 2009, Rio de Janeiro
- X-raying Galaxies: A Chandra
Legacy in the Chandra's First Decade of
Discovery conference, 2009, Boston
- Stellar Feedback and Galaxy
Evolution plenary talk at the Chinese Astronomical Society
Meeting, Kanfeng, 2009
- A Panoramic Hubble Space
View of the Galactic center in Paschen-alpha Emission (press
release at the AAS meeting, 2009, Long Beach)
- How Do Supermassive
Black Holes Get
Starved? at the AAS meeting, 2009, Long Beach
- Global Hot Gas in and around
Galaxy , at the Local Bubble and Beyond II workshop,
Education, CfA, 2007
is getting in and/or out of nearby disk galaxies? ,
Observations: High-energy Processes at arcsecond Resolution, at
Galactic Center Workshop, Bad Honnef, Germany