EM-Holmbeck RProcess

Neutron star mergers eject radioactive material that eventually decays into heavy elements like gold and uranium. But not all mergers are the same: some are heavier, others more asymmetric, and the amount (and properties) of the ejected material changes depending on the merger. Surveys of ancient stars likely contaminated by a single merger event give us an idea of the range of outcomes from these mergers. These outcomes also depend on what neutron stars are made of, as that governs how they are torn apart and thus how much material is ejected.

Recent RIT postdoc Erika Holmbeck just led a novel investigation to use the observed abundances of these ancient stars to constrain the nuclear equation of state. We found a nuclear equation of state that’s surprisingly consistent with other observational avenues, despite using no information from those other channels.

Erika has recently moved on to a Hubble Fellowship at Carnegie observatories in Pasadena.

For more information:

• APS press release about her DNP presentation on 10/13/2021.

• Holmbeck, Delfavero, O’Shaughnessy, Belczynski A Nuclear Equation of State Inferred from Stellar r-process Abundances submitted to ApJ