This research includes studies in theoretical atomic and nuclear physics with emphasis on computer techniques for solving problems in these areas.
In atomic physics, oscillator strengtrhs and electron impact excitation cross sections are calculated. Atomic oscillator strengths are needed for the determination of chemical abundances in the atmospheres of astrophysical objects. Elemental abundance studies are used to address problems related to stellar evolution and chemically peculiar stars, to the interstellar medium, and to cosmology. The need for accurate oscillator strengths is particularly acute in ultraviolet astronomy, because of the dramatic increase in observational capabilities provided by orbiting observatories such as the Hubble Space Telescope. Atomic exciation cross sections are useful for probing the details of atomic structure. Direct measurement of the cross sections is extremely difficult, and theory must be relied on to provide the vast majority of required data.
In nuclear physics, the energy levels of nuclei are calculated in the harmonic oscillator shell model. Such calculations shed light on the nature of the nucleon-nucleon interaction.
Recent Publications:
“Oscillator Strengths for As I – III”, P. S. Ganas, Astron. Astrophys. Suppl. Ser. 143 , 491 (2000).
“Electron Impact Excitation of Si I”, P.S. Ganas, Astron. Astrophys. Suppl. Ser. 138 , 323 (1999).
“Electron Impact Excitation Cross Sections for Phosphorus”, P. S. Ganas, Eur. Phys. J. D 1, 165 (1998).
“Oscillator Strengths for Neutral Selenium and Tellurium”, P. S. Ganas, Astron. Astrophys. 325 , 1280 (1997).