My primary research interest concerns the modeling and analysis of red giant stellar atmospheres, particularly carbon stars and Mira variable stars. In addition to this, I also have interest in the effect that a stellar radiation field has upon a planetary system surrounding the star. There are two large radiative-transfer/stellar-atmosphere’s codes that I run to carry out my research named ATLAS and PANDORA.
ATLAS is a stellar atmosphere's code that numerically solves the radiative transfer equation under the assumption of local thermodynamic equilibrium (LTE) using the lambda-iteration technique. This code was created by R.L. Kurucz of Harvard University's Center of Astrophysics. The version of this code that I use has been modified by the Indiana University group under the direction of H.R. Johnson during the late 1970s and 1980s in order to model cool giant stars. I have been further modifying this code for the past 20 years to improve the calculations of cool star opacities, simplify the input, and generate more detailed output data. My current version of ATLAS contains just under 20,000 lines of FORTRAN 77 code.
PANDORA is an enormous code containing over 5000 subroutines of FORTRAN 77 code. This code is the product of 4 decades worth of work by its creators, E.H. Avrett and R. Loeser of Harvard University's Center for Astrophysics. This is a non-local thermodynamic equilibrium (NLTE) radiative transfer code that uses the equivalent two-level atom approach to solve the radiative tansfer and statistical equilibrium equations. PANDORA is the code that was used to determine the structure of the outer atmosphere of the Sun (the so-called VLA models).
A list of my currect research interests can be found here and results from my past research work can be found by clicking here. One can find many of my published papers by clicking this link.