skip to main content
DOE PAGES title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Split Isobaric Analog State in Ni 55 : Case of Strong Isospin Mixing

Abstract

Study of βþ decay of the exotic T z = -3=2 nucleus 55Cu, via delayed γ rays, has revealed a strongly isospin mixed doublet (4599–4579 keV) in 55Ni, which represents the fragmented and previously unknown isobaric analog of the ground state of 55Cu. The observed small log $ft$ values to both states in the doublet confirm the superallowed Fermi β decay. The near degeneracy of a pair of 3/2 - levels in 55Ni results in the strong isospin mixing. The isospin mixing matrix element between the T = 3/2 and T = 1/2 levels is inferred from the experiment to be 9(1) keV, which agrees well with the matrix element of the charge symmetry breaking shell model Hamiltonian of Ormand and Brown. A precise value of the half-life of 55Cu at 57(3) ms was also obtained.

Authors:
 [1];  [1];  [1];  [2];  [1];  [2];  [2];  [2];  [1];  [1]
  1. Florida State Univ., Tallahassee, FL (United States)
  2. Michigan State Univ., East Lansing, MI (United States)
Publication Date:
Research Org.:
Nuclear Science and Security Consortium, Berkeley, CA (United States)
Sponsoring Org.:
USDOE National Nuclear Security Administration (NNSA)
OSTI Identifier:
1454856
Grant/Contract Number:  
NA0000979
Resource Type:
Accepted Manuscript
Journal Name:
Physical Review Letters
Additional Journal Information:
Journal Volume: 111; Journal Issue: 26; Journal ID: ISSN 0031-9007
Publisher:
American Physical Society (APS)
Country of Publication:
United States
Language:
English
Subject:
74 ATOMIC AND MOLECULAR PHYSICS

Citation Formats

Tripathi, Vandana, Tabor, S. L., Volya, A., Liddick, S. N., Bender, P. C., Larson, N., Prokop, C., Suchyta, S., Tai, P. -L., and VonMoss, J. M. Split Isobaric Analog State in Ni55 : Case of Strong Isospin Mixing. United States: N. p., 2013. Web. doi:10.1103/PhysRevLett.111.262501.
Tripathi, Vandana, Tabor, S. L., Volya, A., Liddick, S. N., Bender, P. C., Larson, N., Prokop, C., Suchyta, S., Tai, P. -L., & VonMoss, J. M. Split Isobaric Analog State in Ni55 : Case of Strong Isospin Mixing. United States. doi:10.1103/PhysRevLett.111.262501.
Tripathi, Vandana, Tabor, S. L., Volya, A., Liddick, S. N., Bender, P. C., Larson, N., Prokop, C., Suchyta, S., Tai, P. -L., and VonMoss, J. M. Thu . "Split Isobaric Analog State in Ni55 : Case of Strong Isospin Mixing". United States. doi:10.1103/PhysRevLett.111.262501. https://www.osti.gov/servlets/purl/1454856.
@article{osti_1454856,
title = {Split Isobaric Analog State in Ni55 : Case of Strong Isospin Mixing},
author = {Tripathi, Vandana and Tabor, S. L. and Volya, A. and Liddick, S. N. and Bender, P. C. and Larson, N. and Prokop, C. and Suchyta, S. and Tai, P. -L. and VonMoss, J. M.},
abstractNote = {Study of βþ decay of the exotic Tz = -3=2 nucleus 55Cu, via delayed γ rays, has revealed a strongly isospin mixed doublet (4599–4579 keV) in 55Ni, which represents the fragmented and previously unknown isobaric analog of the ground state of 55Cu. The observed small log $ft$ values to both states in the doublet confirm the superallowed Fermi β decay. The near degeneracy of a pair of 3/2- levels in 55Ni results in the strong isospin mixing. The isospin mixing matrix element between the T = 3/2 and T = 1/2 levels is inferred from the experiment to be 9(1) keV, which agrees well with the matrix element of the charge symmetry breaking shell model Hamiltonian of Ormand and Brown. A precise value of the half-life of 55Cu at 57(3) ms was also obtained.},
doi = {10.1103/PhysRevLett.111.262501},
journal = {Physical Review Letters},
number = 26,
volume = 111,
place = {United States},
year = {2013},
month = {12}
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record

Citation Metrics:
Cited by: 10 works
Citation information provided by
Web of Science

Figures / Tables:

FIG. 1. FIG. 1. : (Color online) (a) Energy loss spectrum of the secondary beam observed at PIN1. (b) Time difference between a 55Cu implant and a positron detected within the same pixel in coincidence with $γ$ transitions in the daughter 55Ni. (c) High energy portion of $β$ delayed $γ$ spectrum observedmore » for 300 ms after a 55Cu implant, with the transitions in 55Ni marked by energy. (d) Sections of the delayed $γ$ spectrum to highlight decays from the IAS doublet separated by 20 keV.« less

Save / Share:

Works referenced in this record:

From isotopes to the stars
journal, May 2011

  • Thoennessen, Michael; Sherrill, Bradley
  • Nature, Vol. 473, Issue 7345
  • DOI: 10.1038/473025a

Coulomb energy differences between high-spin states in isobaric multiplets
journal, October 2007


Observation of a Large Atomic Parity Violation Effect in Ytterbium
journal, August 2009


γ decay and splitting of the first analog state in Mn 53 , Co 55 , and Cu 59
journal, May 1978


Chaotic Wave Functions and Exponential Convergence of Low-Lying Energy Eigenvalues
journal, March 1999


�ber den Bau der Atomkerne. I
journal, January 1932


β decay of proton-rich nucleus Al 23 and astrophysical consequences
journal, October 2006


MASS MEASUREMENT OF 45 Cr AND ITS IMPACT ON THE Ca-Sc CYCLE IN X-RAY BURSTS
journal, March 2013


High efficiency beta-decay spectroscopy using a planar germanium double-sided strip detector
journal, November 2013

  • Larson, N.; Liddick, S. N.; Bennett, M.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 727
  • DOI: 10.1016/j.nima.2013.06.027

Empirical isospin-nonconserving hamiltonians for shell-model calculations
journal, January 1989


Coulomb displacement energies of the A = 4 n + 3 , T = 1 2 mirror nuclei in the 1 f 7 2 shell
journal, April 1977


Effective interaction for pf -shell nuclei
journal, May 2002


Commissioning the A1900 projectile fragment separator
journal, May 2003

  • Morrissey, D. J.; Sherrill, B. M.; Steiner, M.
  • Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, Vol. 204
  • DOI: 10.1016/S0168-583X(02)01895-5

The decay of proton-rich nuclei in the mass region
journal, August 2007


Variation in Displacement Energies Due to Isospin-Nonconserving Forces
journal, April 2013


Thirty-two-fold segmented germanium detectors to identify γ-rays from intermediate-energy exotic beams
journal, July 2001

  • Mueller, W. F.; Church, J. A.; Glasmacher, T.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 466, Issue 3
  • DOI: 10.1016/S0168-9002(01)00257-1

New “USD” Hamiltonians for the sd shell
journal, September 2006


A study of the (p, d) reactions on A = 12–94 nuclei by 65 MeV polarized protons
journal, July 1980


Delayed Proton Radioactivities
journal, December 1977


Radio Frequency Fragment Separator at NSCL
journal, July 2009

  • Bazin, D.; Andreev, V.; Becerril, A.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 606, Issue 3
  • DOI: 10.1016/j.nima.2009.05.100

Digital Data Acquisition System for experiments with segmented detectors at National Superconducting Cyclotron Laboratory
journal, November 2009

  • Starosta, K.; Vaman, C.; Miller, D.
  • Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, Vol. 610, Issue 3
  • DOI: 10.1016/j.nima.2009.09.016

New effective interaction for p f -shell nuclei and its implications for the stability of the N = Z = 28 closed core
journal, March 2004


Nuclear structure and the search for collective enhancement of {\cal P\hbox{,}T} -violating Schiff moments
journal, August 2008

  • Auerbach, Naftali; Zelevinsky, Vladimir
  • Journal of Physics G: Nuclear and Particle Physics, Vol. 35, Issue 9
  • DOI: 10.1088/0954-3899/35/9/093101

    Figures/Tables have been extracted from DOE-funded journal article accepted manuscripts.