I am an Assistant Professor at the Department of Physics and Astronomy of the University of Pittsburgh.
My research focuses on Type Ia supernova explosions, their binary progenitor systems, and the supernova remnants (SNRs) that they leave behind. Below you can find information on some of my research projects. You can find a complete list of all my publications here (from NASA ADS) and all my preprints here (from the arXiv archive). If you are interested in SNRs in general, I wrote a short review for the 10th anniversary Chandra conference: Badenes 2010, PNAS 107, 7141.
Type Ia SN Explosion Physics from SNRs
Over the years, I have developed a set of models to analyze the X-ray emission from shocked SN ejecta in young Type Ia SNRs. Using these models, it is possible to interpret the X-ray spectra of SNRs like the Tycho SNR (pictured here to the left) obtained with Chandra or XMM-Newton in terms of variables that are relevant for the physics of Type Ia SNe, like the explosion mechanism and the amount of 56Ni synthesized. In some cases, the results can be verified using light echoes from the SN itself (see the press release for SNR 0509-67.5). These X-ray models are publicly available, please contact me if you are interested in using them for your own research.
Type Ia SN Progenitors from SNRs
Because they are much closer than any SN that can be observed from Earth, young SNRs can constrain the properties of Type Ia SN progenitors in many unique ways. One spectacular example is the Kepler SNR (pictured here to the left), a Type Ia object that appears to be interacting with circumstellar material expelled by its progenitor (for more information on this, see the press release and the paper). A few other techniques that I have worked on are:
SNR Dynamics: The radii, shock velocities, and ionization timescales of Type Ia SNRs with known ages can be used to constrain the mass-loss histories of their Type Ia SN progenitors. Relevant Publication: Badenes, Hughes, Bravo & Langer 2007, ApJ 662, 472.
Mn and Cr lines in the X-ray Spectra of SNRs: We have proposed a new method to measure the metallicity of Type Ia SN progenitors directly using weak emission lines from Mn and Cr in the X-ray spectra of bright SNRs like Tycho and Kepler. Koji Mukai put together a nice feature about this work for the Suzaku Learning center, which you can find here. Relevant Publication: Badenes, Bravo & Hughes 2008, ApJ 680, L33.
Stellar Populations Around SNRs: By studying the resolved stellar populations around young Type Ia SNRs, it is possible to constrain the properties of their progenitors. This can be done either for a few specific objects, or for the entire SNR population in galaxies like the Magellanic Clouds. The delay time distribution - the SN rate as a function of time following a hypothetical brief burst of star formation - can be derived in this way, provided the evolution of SNRs in the interstellar medium, and in particular, the distribution of sizes, is understood at least at a basic level. Kurtis Williams published a nice feature about this work in his blog.
Time Resolved Spectroscopy in the Sloan Digital Sky Survey
While I was in Princeton, I started a project to explore the temporal dimension in the spectra taken by the Sloan Digital Sky Survey (SDSS). All SDSS spectra are internally subdivided into three or more ~15 minute sub-exposures, which can be used to explore a number of interesting scientific topics. In collaboration with several people, I have been using these sub-exposures to look for radial velocity shifts in the spectra of white dwarf stars. The goal is to discover short-period white dwarf binaries that might merge due to gravitational wave emission and perhaps become Type Ia SN progenitors. We are calling this the SWARMS (Sloan White dwArf Radial velocity data Mining Survey). And no, we are not particularly proud of the acronym.
Here you can find the pdf files for some talks I have given in the past. I make them available in the hope that someone will find them useful. I make an effort to reference the work of my colleagues properly; if you find that your work is not referenced correctly in these viewgraphs, or you have any questions about the content of the presentations, please contact me.