Department of Physics & Astronomy
University of New Mexico

Nuclear, Particle, Astroparticle and Cosmology (NUPAC) Seminars

Dynamical Evidence For a Fifth Force Explanation of the ATOMKI Nuclear Anomalies

Presented by Dr. Chris Verhaaren (UC Irvine)

Recent anomalies in Beryllium and Helium nuclear decays can be explained by postulating a fifth force mediated by a new boson. The data are consistent with a single mass providing kinematic evidence for a single new particle explanation. I discuss whether the new results also provide dynamical evidence for a new particle explanation, that is, whether the observed decay rates of both anomalies can be described by a single hypothesis for the new boson's interactions. This is done using effective field theory, to determine the leading operators that mediate the decay for various particle spins and parities. From these operators, decay widths can be calculated and compared to the data, giving differing levels of agreement or disagreement for each particle type. Remarkably, both results are consistent with a new vector boson. I also discuss additional measurements that provide additional probes into these intriguing anomalies.

2:00 pm, Tuesday, May 4, 2021

Disability NoticeIndividuals with disabilities who need an auxiliary aid or service to attend or participate in P&A events should contact Sandra Ortiz (phone: 505-277-5900, email: well in advance to ensure your needs are accomodated. Event handouts can be provided in alternative accessible formats upon request. Please contact Mrs. Ortiz if you need written information in an alternative format.

A schedule of talks within the Department of Physics and Astronomy is available on the P&A web site at