Seminars

Tuesday, Jan 22 at 11:00 AM
1200 FRIB Laboratory
Benjamin Bally , UNC Chapel Hill
Multi-Reference Energy Density Functional Calculations of Odd-Mass Nuclei

Abstract:  For more than forty years, the Energy Density Functional (EDF) method has proven to be a useful tool to study low-energy nuclear structure and reactions. In particular, its Multi-Reference (MR) formulation allows the study of complex phenomena that emerge in the strongly-correlated finite quantal system that is the atomic nucleus. The most advanced MR-EDF methods combine efficiently the idea of symmetry breaking and restoration with the mixing of different reference states by the Generator Coordinate Method (GCM) to include important static correlations, such as pairing or deformation, as well as beyond mean-field effects. To this day, it is the most advanced microscopic method at our disposal to tackle heavy-mass nuclei. In this seminar, I will talk about the recent developments achieved to describe odd-mass nuclei within the MR-EDF formalism as well as some of the challenges faced by the practitioners, in particular regarding the effective interactions currently used and the computational limits of such an approach. Indeed, the most advanced MR-EDF methods that combine symmetry restorations and/or configuration mixing are computationally demanding and require large-scale computing facilities. This has to be contrasted with the picturesque idea of EDF approaches as low-cost computing methods.

Wednesday, Jan 23 at 4:10 PM
1200 FRIB Laboratory
Ryan Ringle, Michigan State University
Advancing Penning trap mass spectrometry of rare isotopes at the LEBIT facility

Abstract:  The Low-Energy Beam and Ion Trap (LEBIT) facility [1] at the National Superconducting Cyclotron Laboratory (NSCL) remains the only facility that employs Penning trap mass spectrometry for high-precision mass measurements of rare isotopes produced via projectile fragmentation. This powerful combination of a fast, chemically insensitive rare isotope production method with a high-precision Penning trap mass spectrometer has yielded mass measurements of short-lived rare isotopes with precisions below 10 ppb across the chart of nuclides. The most recent LEBIT measurement campaigns have focused on fundamental interactions such as T=1/2 mirror decay Q-values (11C [2] and 21Na [3]), and superallowed [beta]-decay Q-values (14O [4]), the nuclear mass surface near N=40 (68,69Co [5]), and the rp-process (56Cu [6], 51Fe [7]). Most recently, for the first time LEBIT has been used for post-trap decay spectroscopy. In a proof-of-principle experiment isomerically purified beams of 70Cu were delivered to a decay station installed after the Penning trap. In order to expand the experimental reach of Penning trap mass spectrometry to nuclides delivered at very low rates, the new Single Ion Penning Trap (SIPT) has been built. SIPT uses narrowband FT-ICR detection under cryogenic conditions to perform mass measurements of high-impact candidates, delivered at rates as low as one ion per day, with only a single detected ion. Used in concert with the existing LEBIT 9.4-T mass spectrometer, the 7-T SIPT system will ensure that the LEBIT mass measurement program at NSCL will make optimal use of the wide range of rare isotope beams provided by the future FRIB facility. * This material is based upon work supported by the by the National Science Foundation under Contract No. PHY-1102511 and PHY-1126282. [1] R. J. Ringle, S. Schwarz, and G. Bollen, Int. J. Mass Spectrom. 349-350, 87 (2013). [2] K. Gulyuz, et. al, Phys. Rev. Lett. 116, 012501 (2016). [3] M. Eibach, et. al, Phys. Rev. C 92, 045502 (2015). [4] A. A. Valverde, et. al, Phys. Rev. Lett. 114, 232502 (2015). [5] C. Izzo, et. al, Phys. Rev. C 97, 014309 (2018). [6] A. A. Valverde, et. al, Phys. Rev. Lett. 120, 032701 (2018). [7] W.-J. Ong, et. al, Phys. Rev. C 98, 065803 (2018).

Thursday, Jan 24 at 11:00 AM
1200 FRIB Laboratory
Luke Roberts, FRIB
The Births and Deaths of Neutron Stars: Neutrinos, dense matter, and the r-process
Saturday, Jan 26 at 10:30 AM
1300 FRIB Laboratory
Artemis Spyrou, NSCL
Advanced Studies Gateway Event: Year of the Periodic Table: The synthesis of the elements in the stars and in the lab

Abstract:  The elements we see around us are forged in the burning fires of stars. Nuclear energy and nuclear reactions are driving these fires, and the only way to understand how they work is by producing the relevant nuclei here on Earth and studying their properties. For this reason, among others, the most powerful rare isotope accelerator in the world, FRIB, is currently under construction in the heart of Michigan, on the campus of Michigan State University. Celebrating the International Year of the Periodic Table of Chemical Elements, this talk will focus on how each of the elements and their isotopes can be synthesized inside stars, and how FRIB will give us unique access to the rarest of these isotopes to help us better understand how the universe works.

Monday, Jan 28 at 1:00 PM
1400 Biomedical and Physical Sciences Building
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JINA-CEE Science Cafe - Title to be announced
Friday, Feb 01 at 5:30 PM
1300 FRIB Laboratory
Richard Illman and Hari Kern, Michgian State University
Advanced Studies Gateway Event: Piano and trumpet recital featuring Richard Illman and Hari Kern
Tuesday, Feb 05 at 11:00 AM
1200 FRIB Laboratory
MacKenzie Warren, MSU
Nuclear equation of state sensitivities in multi-messenger signals from core-collapse supernovae

Abstract:  We have explored the dependence of observable features from core-collapse supernovae (CCSNe) on the high-density nuclear equation of state. We have performed simulations of 138 supernovae progenitors ranging from 9-120 solar masses using several equations of state. Using multimessenger electromagnetic, gravitational wave, and neutrino emission from each simulation, we can determine correlations between observable quantities, the equation of state, and fundamental nuclear physics parameters.

Monday, Feb 11 at 12:30 PM
1400 Biomedical and Physical Sciences Building
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JINA-CEE Seminar - Title to be announced