Welcome to my home page. I am a faculty member in the
Department of Astronomy at the
University of Texas at Austin,
and am honored to be the current holder of the Rex
G. Baker, Jr. Centennial Research Professorship in
Astronomy.
My research involves aspects of stellar
spectroscopy, and I am fortunate to have access to the
excellent high-resolution spectrographs of
McDonald Observatory.
Within the past few years through various
collaborations I have also used spectrographic
instrumentation at NOAO Kitt Peak and Cerro
Tololo, Keck, Lick, European Southern, Las Campanas,
and Hubble Space Telescope Observatories.
I study the chemical compositions of stars.
Stars generate nearly all elements of the
periodic table heavier than hydrogen in
their internal fusion cycles (whose primary purpose
is to generate energy). The stars return their newly
minted heavy elements to the interstellar medium gas
clouds at the ends of their lives, either gently in
stellar winds, or violently in nova or supernova
explosions. Newly forming stars then gather
up this enriched gas. So with each succeeding
stellar generation the heavy
element content builds up in the Galaxy.
I have concentrated on spectroscopic studies of old
stars: either giant stars of the Galactic disk that
are nearing the end of their lives, or long-lived
stars of the old Galactic halo. Analysis of Galactic
halo stars especially intrigues me, for these stars
were born near the start of the Galaxy and therefore
their chemical compositions hold vital clues to
"early Galactic nucleosynthesis", or heavy element
generation at the beginning of our Galaxy.
More Information
Further discussion of my research on Galactic
halo stars can be found at
HALOSTARS page.
Further discussion of my research on Galactic
disk stars can be found at
DISKSTARS page.
My work in support of lab studies of atomic/molecular
transition data is at
LABDATA page.
To learn about my spectrum analysis programs, please
see the
MOOG
&
SPECTRE pages.
For the information on courses that I often teach,
please go to
TEACHING.
For a list of my past and present graduate students,
please see
STUDENTS.
My refereed journal publications are listed at the
NASA Astrophysical Data Service; click on
JOURNAL PAPERS.
My un-refereed (mainly conference) publications are
also listed at the NASA ADS; click on
CONFERENCE PAPERS.