Photon Escape from the Interstellar Medium

• Applicant: Dr. Benedetta Ciardi
• Subject Area: Astrophysics and Astronomy
• Term: from 2011 to 2014
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 203258417

The physics of the interstellar medium (ISM) plays a crucial role in many areas of astronomy and astrophysics, from the formation of planets on small scales, to the evolution of the intergalactic medium (IGM) on large scales. The latter in turn has a very tight interplay with the galaxy formation and evolution process via different feedback effects, such as metal enrichment and reionization, which can alter the IGM thermal state, reduce gas accretion or even evaporate gas in small mass galaxies. The understanding of the physics of the ISM is thus of paramount importance for the broader understanding of how the universe we observe today has taken shape. This because the amount of radiation emitted by galaxies into the IGM depends, among others, on the abundance of stars within a galaxy, their distribution, as well as the distribution of neutral gas and dust within the ISM. Despite its relevance, and much recent theoretical and observational progress in the investigation of the ISM, many important questions still remain open. Among which, those related to the escape of photons from the ISM into the IGM. Recent empirical measurements of the escape fraction in the local universe and at high redshift have generally produced modest values in the range of a few percent. In contrast, theoretical studies have largely been inconclusive. Here we propose to investigate this important open problem using state of the art 3D hydro-dynamical and radiative transfer simulations.

• DFG Programme: Priority Programmes
• Subproject of: SPP 1573: Physics of the Interstellar Medium