My Former Research Mentors

I have stood on the shoulders of giants to get where I am today and would be completely remiss not to mention at least of few of them here:

  • Dr. Richard A. Wade
    (2011-2013, Penn State)

    worked together on various hot subdwarf projects, including a radial velocity survey of hot subdwarfs with main sequence companions, a search for hot subdwarfs around F stars, and various other projects.

  • Dr. J. Christopher Clemens
    (2006-2011, UNC)

    my PhD advisor; worked together on commissioning the Goodman spectrograph on the SOAR telescope, white dwarf research projects, and studies of hot subdwarfs; introduced me to astronomical instrumentation and taught me how to conduct my own scientific research and publish papers.

  • Dr. Patrick Lestrade
    (2002-2006, Miss. State. Univ)

    introduced me to research for the first time as a freshman physics major; worked together on characterizing the gamma-ray background from the HETE-2 satellite. Together, we discovered the Ecuador Anomaly, a dip in the Earth’s magnetic field similar to the South Atlantic Anomaly. Our discovery was later “scooped” by another research group! I was hooked on astronomical research after this moment.

  • Mr. Powell
    (2000-2002, St. Martin High School)

    taught me astronomy and physics in high school; check out his website.

Current Student Projects

HPU Physics Majors:





The Binarity of Helium-Dominated Hot Subdwarfs Eugene Filik in Chile
Eugene Filik - sophomore

Eugene will obtain high-resolution spectroscopy of several helium-dominated hot subdwarf stars in the Southern Hemisphere to look for signs of binarity. In particular, he will look for double-lined binaries that he can follow-up in order to determine their orbital periods and velocities.



Modeling a Binary Star with Pulsating Primary
Stephen Vultaggio - senior

Astronomers at Calvin College recently discoverd a new eclipsing binary star system containing a hot subdwarf. Follow-up observations we obtained with the SOAR telescope reveal that the hot subdwarf is also a pulsating star! As both the pulsation and binary elements of the light curve reveal information about the hot subdwarf's properties, this system will provide strong constraints on theoretical models of hot subdwarfs. Stephen Vultaggio is currently trying to model the light curve by taking into account all of the binary effects, and all of the pulsation modes.


Pulsar Companion Identification Eugene Filik, Aaron Marlowe, and Tyler Hockett at the BLANCO 4-m in Chile
Eugene Filik, Aaron Marlowe, Tyler Hockett

During an observing run on the SMARTS 0.9-m in Chile in May 2014, the guys received a request to take a deep optical image to help identify the companion to a newly-discovered pulsar. We have finished processing the images and completed the analysis. On August 22nd, we submitted a manuscript for publication in Astrophysical Journal Letters, and it is now under peer review.

Past Student Projects

HPU Physics Majors:


Search for Pulsating SdB Stars Don Winget, Stephen Vultaggio, Brad Barlow
Stephen Vultaggio - junior

Stephen and I are conducting a photometric survey with the 0.4-m PROMPT telescopes in Chile to look for new rapidly-pulsating hot subdwarf B (sdB) stars. Every couple of days, Stephen obtains time-series photomtery of another sdB star with PROMPT, which allows him to construct a light curve (brightness versus time plot) over several hours. A Fourier transform of the light curve is calculated in order to look for small-amplitude variations in the light output from the star. Each new pulsating sdB star discovered allows the tools of asteroseismology to be applied to the hot subdwarfs in order to determine their mass, size, and overall structure. Although he's only been looking for a few months, he appears to have already discovered a new pulsating star!!!



Monitoring Comet ISONComet ISON
Aaron Marlowe and Sam Gordon - freshmen

Aaron and Sam monitored the progress of Comet ISON as it approached the Sun in November 2014. They used the PROMPT telescopes to measure the comet's position day by day. These measurements will allow them to determine the orbit of the comet. The colored photo at left was constructed from several black-and-white images they obtained using the robotic PROMPT telescopes in Chile.



Post-Baccalaureate Students:


Ms. Sandra E. Liss

worked on measuring orbital periods for hot subdwarf stars with main sequence companions and reduced years of Hobby-Eberly Telescope spectroscopic data in the process. She is now a second-year graduate student in the Department of Astronomy at the University of Virginia. Check out her publications here.

High School Students:


Mr. Arjun Raghavan

measured the amplitudes of known pulsating hot subdwarf stars and detected amplitude changes in many of them. For his work, he was recognized in the Intel Science and Engineering Fair and the Siemens Competition in Math, Science, and Engineering. He is currently a Robertson Scholar at Duke and UNC. Check out WNCN's "This Kid Rocks!" segment on him.
Image Credit: SPIE