Radio-Far-infrared Correlation in Ultra Luminous Infrared Galaxies and the Role of Secondary Cosmic Ray Electrons

Prof. Thinniyam Rengarajan

Tata Institute of Fundamental Research, India

Tuesday - Dec. 04, 2007

3:30pm - 4:30 pm

218 - Natural Science Center

Abstract:

The radio--far-IR correlation is ubiquitous and wide ranging. The tight correlation seen in a variety of galaxies holds good even in compact (100 pc) Ultra-Luminous Infrared Galaxies. It has been suggested that high magnetic fields (of milligauss strength) may maintain the correlation by preventing the dominance of inverse Compton scattering. I will discuss some issues of nonlinearity of the correlation in general, as well as the problems posed by high magnetic fields. Secondary cosmic ray electrons, which may be copiously be produced in these high density regions may offer a solution. I will also talk about future observations that may help in elucidating the problem.