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Prospects for Calibrating the New Physics Sensitivity of <sup>229</sup>Pa

ORAL

Abstract

A non-zero permanent electric dipole moment (EDM) would violate parity (P) and time-reversal (T) symmetry, and through the CPT theorem, charge-parity (CP) symmetry is also violated. New sources of CP-violation are necessary to explain the observed baryon asymmetry of the Universe. Detecting a non-zero EDM with current or planned levels of sensitivity would provide evidence for new sources of CP-violation. This nuclear EDM is partially screened by its atomic electrons which are described by the Nuclear Schiff Moment (NSM). The NSM is responsible for inducing the atomic EDM we are seeking to observe. We aim to search for a nearly degenerate ground state parity doublet in 229Pa (Z = 91, τ=1.5 d, I=5/2). If this parity doublet exists, which is thought to have energy splitting consistent with 60 ± 50 eV, then this would significantly enhance the lab-frame NSM and would provide strong motivation for a future search for an NSM of 229Pa, which may be 106 times larger than the NSM for 199Hg. In this presentation, gamma-ray and internal conversion spectroscopy techniques are being explored in order to determine the precise nature of the parity doublet if it exists.

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Presenters

  • Adrian M Yearby

    Michigan State University

Authors

  • Adrian M Yearby

    Michigan State University

  • Jonas N Becker

    Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824, USA

  • Robert Berger

    Department of Chemistry, Philipps-Universität Marburg, Marburg 35032, Germany

  • Anastasia Borschevsky

    Department of Science and Engineering, Univ. of Groningen, Groningen 9700, Netherlands

  • Stephan Friedrich

    Lawrence Livermore National Laboratory, Livermore, CA 94550, USA

  • Alyssa Gaiser

    Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, USA

  • Ronald Fernando Garcia Ruiz

    MIT, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02142, USA, MIT Laboratory for Nuclear Science

  • Wick Haxton

    Department of Physics, University of California-Berkeley, Berkeley, CA 94720, USA

  • Andrew Jayich

    Department of Physics, University of California-Santa Barbara, Santa Barbara, CA 93106, USA

  • Kyle G Leach

    Colorado School of Mines, Department of Physics, Colorado School of Mines, Golden, CO 80401, USA

  • Sean N Liddick

    Michigan State University, FRIB, FRIB/NSCL, Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, USA, FRIB/MSU

  • Jeffery Martin

    Department of Physics, University of Winnipeg, Winnipeg, Manitoba R3B2E9, Canada

  • Shannon Nicley

    Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI 48824, USA

  • Chandana S Sumithrarachchi

    Michigan State University, Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, USA

  • Silviu M Udrescu

    Massachusetts Institute of Technology, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA 02142, USA

  • Jaideep T Singh

    Michigan State University, Facility for Rare Isotope Beams, Michigan State University, Facility for Rare Isotope Beams, Michigan State University, East Lansing, MI 48824, USA