Seminars

Tuesday, Feb 20 at 11:00 AM
NSCL Lecture Hall 1200
ChiehJen (Jerry) Yang, George Washington University
New approaches to nuclear forces

Abstract:  This talk concerns several recent approaches using effective field theory (EFT) to describe nuclear system. First, on the nucleon-nucleon (NN) interaction level, to resolve the issue of the conventional chiral EFT approach (Weinberg power counting), a new power counting which is free of the renormalization group problem is introduced. Then we propose a new way to apply the EFT interaction in truncated model space to perform ab-initio calculations. Finally, recent approaches toward a systematic treatment of effective interactions within the energy density function (EDF) framework will be discussed. Results of nuclear matter up to NLO based on this approach will be presented.

Wednesday, Feb 21 at 1:00 PM
NSCL Lecture Hall 1200
Wei Jia Ong, NSCL
Quantifying the URCA cooling impact of mass 61 nuclei in x-ray bursting systems

Abstract:   COMMITTEE: Hendrik Schatz(Chairperson),Edward Brown, Alexandra Gade, Carl Schmidt,Artemis Spyrou Thesis is on display in 1312 BPS bldg. and the NSCL atrium

Wednesday, Feb 21 at 4:10 PM
NSCL Lecture Hall 1200
K. Renee Horton, Unapologetically Being, Inc., Founder
You can have your dream

Abstract:  Everyone\'s journey is unique and filled with big and small obstacles. Dr. Renee Horton has experienced obstacles and still has succeeded in pursuing her dream. The talk, You Can Have your Dream, travels Renee’s path through failures, small success, obstacles, disappointments and finally landing in her dream job. Renee currently serves as the Metallic/Weld Engineer for NASA Space Launch System (SLS) in New Orleans, LA, which comes full circle after dreaming as a child on working for NASA as an astronaut. She may not be an astronaut, but she helps put them into space. Renee believes that if you find your intersection between your talent and your passion, you find your true happiness; this talk will highlight her dissertation studying Self Reacting Friction Stir Welding, her non-profit she founded and the overall intersectionality of her life.

Thursday, Feb 22 at 11:00 AM
NSCL Lecture Hall 1200
Tenzin Ragba, NSCL
Upgrades for an improved measurement of the permanent Electric Dipole Moment of Ra-225

Abstract:  A non-zero Electric Dipole Moment (EDM) in a non-degenerate system violates time-reversal (T) symmetry, and therefore charge-parity (CP) symmetry due to the CPT theorem. EDM measurements are therefore sensitive and background-free searches for new CP violating interactions. Ra-225, with its octupole deformation and nearly degenerate nuclear parity doublet, is an extremely attractive candidate for probing CP violations in the hadronic sector. Our latest measurement limits the EDM of Ra-225 to be less than 1.4x10^(-23) e-cm (95% CL), and is the first ever measurement of an EDM limit using laser cooled and trapped atoms. Further experimental upgrades are being implemented including an electric field upgrade to enhance the EDM sensitivity and STIRAP-based electron shelving for improved state detection efficiency. With these upgrades in place our EDM sensitivity should increase by about two orders of magnitude and allow us to substantially improve constraints on certain T-violating processes within the nucleus. Updates on the status of these upgrades will be provided.

Monday, Feb 26 at 12:00 PM
NSCL Lecture Hall 1200
Amy Lovell, NSCL
A deeper understanding of the inputs for reaction theory through uncertainty quantification

Abstract:  COMMITTEE: Filomena Nunes(Chairperson),Morten Hjorth-Jensen, Witold Nazarewicz, Brian O’Shea, Artemis Spyrou

Tuesday, Feb 27 at 11:00 AM
NSCL Lecture Hall 1200
Rodolfo M Id Betan, Institute of Physics Rosario Ocampo and Esmeralda, Santa Fe, Argentina
Shadow poles in a coupled-channel problem calculated with Berggren basis

Abstract:  In coupled-channel models the poles of the scattering S-matrix are located on different Riemann sheets. Physical observables are affected mainly by poles closest to the physical region but sometimes shadow poles have considerable effect, too. The purpose of this paper is to show that in coupled-channel problem all poles of the S-matrix can be calculated with properly constructed complex-energy basis. The Berggren basis is used for expanding the coupled-channel solutions. The location of the poles of the S-matrix were calculated and compared with an exactly solvable coupled-channel problem: the one with the Cox potential. We show that with appropriately chosen Berggren basis poles of the S-matrix including the shadow ones can be determined.

Monday, Mar 12 at 12:30 PM
Biomedical & Physical Sciences Bldg., Rm. 1400
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Title to be announced
Thursday, Mar 15 at 12:30 PM
NSCL Lecture Hall 1200
Hsiao-Chaun (Dick) Hseuh, ANL/FRIB
Vacuum Technology for Particle Accelerator

Abstract:  Abstract: Part II – The selection of vacuum materials and treatment will be described. The vacuum system design, engineering, implementation and operation will be demonstrated through examples, some applicable to FRIB. The first part was presented on November 16, 2017 and it is available here https://portal.frib.msu.edu/Lists/Announcements/AllItems.aspx

Tuesday, Mar 20 at 11:00 AM
NSCL Lecture Hall 1200
Jimmy Rotureau, NSCL
Title to be announced