Dr. Richard Freedman

December 21, 2006

“Research in Molecular Spectroscopy and the Atomic and Molecular Opacity of Brown Dwarfs and Extra Solar Giant Planets”

NCC 2–1357

The study of brown dwarfs, objects whose mass is too low to support hydrogen fusion in their interior, has made great progress in the past few years. As more of these objects have been discovered it has become important to understand their properties. These objects are strong emitters in the infra red region of the spectrum because of their relatively low effective temperatures as they are powered only by the energy from gravitational contraction.This work on the opacity sources of these objects uses data on atomic and molecular absorption to produce predictions of the opacity that are incorporated into atmospheric models by my collaborators. These models can then be used to study their spectra, colors, and overall physical properties.

The continuing discovery and cataloging of extra solar giant planets has been proceeding over the past few years. This work is also directly applicable to this field as the physical conditions that govern the opacity in these objects are very similar to those in brown dwarfs. The PI has also been providing calculations for the modeling of these objects.

The PI has been involved in the measurement of high resolution laboratory data of various molecular species in order to derive data on their line strengths and broadening coefficients. This data has also been used to investigate the physical properties of these molecules such as dipole moment functions and potentials.