The need for accurate atomic physics data to understand photon emission from comets

S. OTRANTO, R.E. OLSON, P. BEIERSDORFER

Freiburg, Alemania

Conferencia; XXV International Conference on Photonic Electronic and Atomic collisions (ICPEAC); 2007

      In the last few years, spectroscopic observations of comets gained the attention of the astrophysical as well as the atomic physics community [1-4].        The detection of X-ray emission from comets (so far considered surprising due to them being cold objects), puzzled theoreticians who inmmediatly searched for different explanations for such emission.         By the year 2000, and after the Chandra X-ray Observatory (CXO) focused on comet Linear C/1999 S4 right before its breakup, the charge exchange process between the solar wind ions and the cometary gases in the comet coma was finally recognized as the main responsible mechanism for the detected emission. The strong line measured at 561 eV corresponding to the 23S