Research

Extrasolar Planets

Independent undergraduate project funded by Wyoming NASA Space Grant Consortium and conducted in collaboration with a fellow undergraduate, Laura Portscheller. Project consisted of taking optical observations of the open cluster NGC 188 at Red Buttes Observatory during the 2006-2007 academic year. Analysis of the data included using the IRAF task DAOPHOT to extract apparent magnitudes of ~ 400 stars within NGC 188 and analyze stellar variability caused by a possible transiting planet. Preliminary results showed our observations and analysis gave us a precision of ~ 0.02 magnitude difference at best, constraining the lower limit size of an extrasolar planet to several Jupiter radii. Assuming a solar-type star with 90° inclination relative to us, a magnitude difference of 0.01 amounts to a planetary transit with a physical size of ~ 1.2 Jupiter radii. Additionally, the lack of continuous observations limits the scope of our project to detection of short-period planets, on the order of several days. Preliminary results provided semi-transits for 3 Cepheid/W Ursae Majoris stars. Improvements to the reduction process are being done now and I hope to have all the nights reduced by the beginning of the summer of 2008.

*Submitted report to Wyoming NASA Space Grant Consortium - Final Report (PDF)

Reverberation Mapping

Assisted with Nordic Opitcal Telescope (NOT) monitoring collaboration between Dr. Mike Brotherton (University of Wyoming) and Dr. Margrethe Wold (Institute of Theoretical Astrophysics - University of Oslo). The NOT monitoring program is an international collaboration between 4 observatories, including the Wyoming Infrared Observatory, attempting to continuously monitor ~ 30 variable quasars of intermediate black hole mass. Reverberation mapping is a means to ascertain quasar characteristics by observing its variability. Specifically, the observed time delay of a quasar's Broad Line Region can be used to probe the quasar's inner workings, allowing measurements of black hole mass, size and internal stucture. My work primarily consisted of observing all NOT quasars at the Wyoming Infrared Observatory in Johnson V and R filters during the 2006-2007 academic year and summer of 2007. All observed objects were calibrated (bias/dark subtraction and flat fielded) and sent to Dr. Wold where our data was combined with additional collaboration data to form light curves of the quasar Broad Line Region.

Post-Starburst Quasars

Currently reducing infrared Post Starburst Quasar (PSQ) data taken at the Infrared Telescope Facility. Analysis consists of using the IRAF task XMOSAIC to co-add individual PSQ images into one master image, then creating a model PSF by using XMOSAIC to co-add standard star images into a single master Point Spread Function (PSF). A standard star is observed before every PSQ for two main reasons: a central AGN can be approximated as a point source and observing a standard prior to observing a PSQ can account for atmospheric changes and conditions. Hopefully, by using the standard PSF I'm able to account for any changing seeing conditions throughout the night, allowing me to accurately subtract out the centeral AGN from the galaxy. After normalizing the PSF peak to the galaxy peak I subtract the two master images until I have just the galaxy contribution, giving me the light fraction of galaxy/total and subsequently, the AGN contribution. In addition, I use the IRAF task ELLIPSE to calculate the isophotal intensity as a function of galaxy radius, allowing me to make a surface brightness profile for each galaxy. The surface brightness profile is then used in conjunction with the Sérsic Law to establish galaxy-type and effective radius.

*Preliminary results for April 2005 Observing Run and September 2005 Observing Run

*Data reduction method - PSQ reduction (PDF)

*PSQ observation notes and results can be found here (PDF) and here (PDF)