Graduate

I am interested in a wide range of problems in observation-based stellar astronomy, and also enjoy teaching and outreach.

During the summer of 2012, I am working with Jason Jackiewicz and Patrick Gaulme to study asteroseismology in binary star systems. My experience analyzing a combination of light curves and radial velocities allows us to model and remove the "unwanted" eclipse information from a light curve so that the physically interesting seismic data remain. Asteroseismology is the analysis of stellar pulsations to directly observe the interiors of stars, a realm which is otherwise invisible. We are using light curves of eclipsing giant stars from the Kepler mission and ground-based spectra from Apache Point and Kitt Peak Observatories.

I spent the summer of 2011 in Bangalore, India as a participent in the IRES program at the Indian Institute for Astrophysics. While abroad, I became familiar with the binary modeling program PHOEBE and analyzed archival light curves of eclipsing binary stars in the Large Magellanic Cloud with advisor M. S. Rao. I also had the opportunity to visit observatories near Bangalore and eat lots of delicious food!

The topic of my M.S. thesis at San Diego State was determining neutron star masses in eclipsing X-ray binaries, with advisor Jerry Orosz. We used the Eclipsing Light Curve (ELC; see Orosz & Hauschildt 2000) numerical code, which employs a genetic algorithm, to model six systems. Our technique allows an arbitrary number of input parameters to be included in an orbital solution. ELC also employs a key improvement over analytic methods: it uses Roche geometry with equipotential surfaces to more accurately model optical light curves and the X-ray eclipse duration. Our results show a clear distribution of neutron star masses that span a range from ~0.9 - 2 solar masses.

Undergraduate

My senior thesis at Harvey Mudd was titled Ups and Downs in the Life of a Cataclysmic Variable: The Long-Term Behavior of CM Phoenicis, completed with advisor Don Hoard. I combined optical and near-infrared photometry of an unusual cataclysmic variable star with optical spectroscopy to explore the secular evolution of an interacting binary star. Our analysis showed transitions between bright and faint states, and we classified CM Phe as a VY Scl-type system.

This work was complemented by a summer project at the Carnegie Observatories spent deriving photospheric chemical composition for metal-poor globular cluster stars from high resolution spectra. I traveled twice with Inese Ivans to Las Campanas Observatory in Chile, and took control of the Clay Magellan 6.5-meter telescope for two nights to obtain high-resolution optical spectroscopy.

I also assisted in the analysis of supernova light curves during a semester abroad at Moscow State University in Moscow, Russia. I have a basic understanding of the Russian language.

Publications

Light Curve Solutions of Eclipsing Binaries in the Large Magellanic Cloud
Meredith L. Rawls & M. S. Rao
2012, AASMA, 219, #153.41

Refined Neutron Star Mass Determinations for Six Eclipsing X-Ray Pulsar Binaries
Meredith L. Rawls, J. A. Orosz, J. E. McClintock, M. A. P. Torres, C. D. Bailyn, & M. M. Buxton
2011, ApJ, 730, 25

New Observations and Neutron Star Mass for the X-ray Binary 4U 1538-52
Meredith L. Rawls, J. A. Orosz, J. E. McClintock, M. A. P. Torres, C. D. Bailyn, & M. M. Buxton
2010, BAAS, 42, #453.20

Time-resolved Photometry of Two New SU UMa Dwarf Novae: V466 Andromedae and OT J011306.7+215250
Allen W. Shafter, R. Babar, A. E. Burke, M. Fernandez, Z. R. J. Girazian, C. M. Heffner, S. Kadakia, D. A. Krogsrud, E. Marin, M. L. Rawls, & J. S. Rice
2009, BAAS, 41, #491.08

Refining the Neutron Star Mass Determination in Six Eclipsing X-ray Pulsar Binaries
Meredith L. Rawls & J. A. Orosz
2009, BAAS, 41, #410.03

Ups and Downs in the Life of a Cataclysmic Variable: The Long-Term Behavior of CM Phoenicis
Meredith L. Rawls, D. W. Hoard, & S. Wachter
2007, BAAS, 39, #51.23

Curriculum Vitae