Expansion and ongoing cosmic ray acceleration in HESS J1731-347
With the help of two Chandra observations separated by 13 years, we were able to measure the expansion rate and rapid variability of brightness of individual X-ray filaments in a VERY peculiar supernova remnant (SNR) HESS J1731-347. That's the same one which hosts a strange star candidate we found earlier. Measuring expansion rate implies that we can measure expansion velocity and age of the remnant and compact object at the centre and may have important implications for our understanding of neutron/strange star cooling. On the other hand, observed rapid variability implies that the magnetic field around the filaments is very strong and must be able to contain not only electrons but also heavier particles during acceleration. Potentially up to PeV energies! The results have been published in A&A.
