Connecting Nuclear Structure to Stellar Astrophysics: Neutron Skin in Tin Isotopes

ORAL

Abstract

The first observation of a neutron star merger by the LIGO-Virgo collaboration in 2017 highlights the need to improve our fundamental understanding of the equation of state (EOS) of dense, neutron rich matter. The origin of heavy elements in the r-process and the structure of neutron stars are governed by the properties of neutron rich matter, for which experimental data is limited. Further analysis of this historic event and all future neutron star mergers relies on constraining the nuclear EOS with experimental observables. We propose a novel method for systematically studying the evolution of the neutron skin in stable tin isotopes, by measuring the low-energy nuclear dipole strength over the broadest possible range of neutron-to-proton ratios in a single element. Nuclear resonance fluorescence with 100% linearly polarized photons from the High Intensity $\gamma$-ray Source (HI$\gamma$S) facility was used to selectively measure the E1 photoabsorption strength of $^{112}$Sn and $^{124}$Sn at excitation energies from $\sim3$ MeV up to neutron separation, where the Pygmy Dipole Resonance dominates.

*This work was performed under the auspices of US DOE by LLNL under contract DE-AC52-07NA27344.

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Authors

  • Jack Silano

    • Lawrence Livermore National Laboratory

  • Anton Tonchev

    • Lawrence Livermore National Laboratory

  • Anthony Ramirez

    • Lawrence Livermore National Laboratory

  • Nicolas Schunck

    • Lawrence Livermore National Laboratory

  • Werner Tornow

    • Duke University and Triangle Universities Nuclear Laboratory

  • Sean Finch

    • Duke University and Triangle Universities Nuclear Laboratory

  • Fnu Krishichayan

    • Duke University and Triangle Universities Nuclear Laboratory

  • David Little

    • The University of North Carolina at Chapel Hill and Triangle Universities Nuclear Laboratory

  • Michael Jones

    • The University of North Carolina at Chapel Hill and Triangle Universities Nuclear Laboratory

  • Robert Janssens

    • The University of North Carolina at Chapel Hill and Triangle Universities Nuclear Laboratory

  • Cole Pruitt

    • Washington University, St. Louis

  • Lee Sobotka

    • Washington University, St. Louis

  • Adriana Banu

    • James Madison University

  • Jayson Vavrek

    • Massachusetts Institute of Technology

  • Nadia Tsoneva

    • ELI-NP