Stony Brook University
7:30 pm
ESS Building, Room 001
Friday, February 07, 2025
The History of the r-Process, or a History of Misogyny
Prof. James Lattimer
The question of where half the nuclides heavier than iron originated has been a long-standing question in physics and astronomy. Long thought to be the progeny of supernovae, the multi-messenger observation of the first neutron star merger, GW1170817, by gravitational wave, gamma ray and optical observatories may have led to a paradigm shift. A largely ignored idea the speaker, and his advisor David N. Schramm, proposed fifty years ago that r-process elements could be synthesized in mergers involving neutron stars has now become a leading explanation. The merger of two inspiralling neutron stars produced the observed gravitational waves and was followed within 2 seconds by a gamma-ray burst produced by a newly-formed black hole. The merger also led to the ejection of nearly a tenth of a solar mass of extremely neutron-rich matter. Thermalized gamma rays from r-process nucleosynthesis in this expanding material were the likely source of the observed afterglow in the galaxy NGC 4993, 40 million parsecs away. The idea of the r-process, and its name, was developed 68 years ago following extensive geochemical and nuclear research. Ever since then, the debate about where it happens has raged. The story involves, among others, at least 15 Nobel Laureates and episodes of misogyny. The speaker will point out how the world has even regressed in the interim.
Prof. Lattimer, a Distinguished Professor in the Physics & Astronomy Department of Stony Brook University, is a long-time resident of East Setauket and a former Chairperson of the Earth and Space Sciences Department. He has received Sloan and Guggenheim Fellowships, is a Fellow of both the American Astronomical and American Physical Societies, and has received the latter's highest award in nuclear astrophysics, the Hans A. Bethe Prize. His outside interests include his grandchildren and ferroequinology. Misogynists and others who pose threats to our children and grandchildren through their support of anti-vaxxing and anti-science policies may feel uncomfortable by attending.
