Evan Meekins presenting in front of the JMU STEM Executive Advisory Council on Oct. 17, 2014 |
How nuclear reactions in stars and stellar explosions such as supernovae have forged the elements out of hydrogen and helium leftover from the Big Bang is a longstanding, still timely research topic in nuclear astrophysics. Although there is a fairly complete understanding of the production of the chemical elements and their isotopes up to iron by nuclear fusion in stars, important details concerning the production of the elements from iron to uranium remain puzzling. Current knowledge is that the nucleosynthesis beyond iron proceeds mainly via neutron capture reactions and subsequent electron decays to the valley of stability. But some 35 proton-rich stable isotopes, between Se-74 and Hg-196, cannot be synthesized by neutron-capture processes since they are located on the neutron-deficient side of the valley of stability. These proton-rich nuclides are generally referred to as p-nuclei. Among them, the two isotopes of molybdenum, Mo-92 and Mo-94, are the most abundant.
Evan Meekins has recently carried out successfully cross section measurements for understanding the production of Mo-93 via neutron photodesintegration of Mo-94, an experiment proposed by Evan's research advisor, Dr. Adriana Banu (an assistant professor in the Department of Physics and Astronomy at JMU). The measurements were performed using the most intense quasi-monoenergetic gamma ray facility in the world located on the campus of Duke University at Durham, NC. Data analysis is in progress. Stay tuned for our experimental findings!
Moreover, Evan Meekins has also had the chance to showcase his work related to the nucleosynthesis of the p-nuclei during the Conference Experience for Undergraduates (CEU14) held in Waikoloa, Hawaii (October 7-11, 2014) in conjunction with the 4th joint meeting of the American Physical Society Division of Nuclear Physics (DNP) and the Physical Society of Japan.
Poster presentation at the CEU14, Hawaii |
The goal of the CEU is to provide a "capstone" conference experience for undergraduate students who have conducted research in nuclear physics, by providing them the opportunity to present their research to the larger professional community and to one another. Additionally, it enables the students to converse with faculty and senior scientists from graduate institutions about graduate school opportunities.