Final Report Summary - SUSYBREAKING (Supersymmetry Breaking in String Theory)
The project developed novel connections between string theory accounts of the early universe and X-ray astrophysical phenomena in clusters of galaxies. We developed new search strategies for axions - a type of conjectured particle that often occurs in string theory. We showed that string theory axions offer a explanation for a long-standing excess in the softest X-rays in the spectrum of galaxy clusters. By constraining spectral modulation in Active Galactic Nuclei, we placed the strongest bounds yet on the existence of axions and also found a possible candidate signature of dark matter, involving an absorption line at 3.54 keV from the central Active Galactic Nucleus of the Perseus galaxy cluster.