Neutron Star Merger Remnants
Search for Old Neutron Star Merger Remnants in the Solar Neighbourhood
Binary neutron star mergers have been identified as the sources of short gamma-ray bursts (GRBs) from the joint detection of the LIGO/Virgo gravitational event GW170817 and a short GRB about two seconds later from the same direction. Neutron star mergers are believed to produce major amounts of high mass nuclei beyond the iron peak elements, such as gold, platinum, and uranium, among others. The process to create these elements is the so-called r-process, which works by rapid neutron capture, faster than the decay times of neutron rich material at the neutron drip line of the table of isotopes.
Neutron star mergers, besides the prompt GRB, have a delayed gamma-ray signal from the decays of a multitude of radioactive isotopes. Depending on the age of the remnant, diferent isotopes would be dominant. In the Milky Way, no remnant has been identified as being due to a neutron star merger, and there was also never a search for mergers in the vicinity of the Sun. However, there could be a single 10000 yr old remnant very nearby (<500 pc), which could be seen by even current gamma-ray telescopes.
In this Bachelor thesis, the sky will be searched for old neutron star merger remnants in the gamma-ray lines of Sn-126 (666 & 695 keV) to define the sensitivity of this search in terms of distance, ejecta mass, and observational strategy with INTEGRAL/SPI.
More information:
Recent Publications:
- LIGO/Virgo, Fermi, INTEGRAL 2017, https://arxiv.org/abs/1710.05834
- Wu et al. 2019, https://arxiv.org/abs/1905.03793
Contact persons:
Dr. Thomas Siegert: thomas.siegert@uni-wuerzburg.de
