Corrections to the single-particle M1 and Gamow-Teller matrix elements

In many shell model interactions, the tensor force monopole matrix elements often retain systematic trends originating in the bare tensor force. However, in this work, we find that Isospin [Formula: see text] tensor force monopole matrix elements of widely used p-shell effective interaction CK(8–16) do not share these systematic. We correct these discrepancies by modifying [Formula: see text] tensor force two-body matrix elements (TBMEs) of CK(8–16) by the analytically calculated tensor force TBMEs. With some additional modification of single-particle energies and TBMEs, the revised effective interaction is named as CKN. The effective interaction CKN has been tested for the calculations of p-shell nuclei of normal parity states from various physics viewpoints such as excitation spectra, electromagnetic moments, and electromagnetic and Gamow–Teller (GT) transitions. The obtained results are found to be satisfactory with respect to the experimental results.

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Corrections to the free-nucleon values of the single-particle matrix elements of theM1and Gamow-Teller operators, from a comparison of shell-model predictions withsd-shell data

Physical Review C ◽

10.1103/physrevc.28.2397 ◽

1983 ◽

Vol 28 (6) ◽

pp. 2397-2413 ◽

Cited By ~ 94

Author(s):

B. A. Brown ◽

B. H. Wildenthal

Keyword(s):

Shell Model ◽

Single Particle ◽

Matrix Elements ◽

Free Nucleon ◽

Model Predictions ◽

Gamow Teller

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Two-phonon structures for beta-decay theory

EPJ Web of Conferences ◽

10.1051/epjconf/201819402008 ◽

2018 ◽

Vol 194 ◽

pp. 02008

Author(s):

A.P. Severyukhin ◽

N.N. Arsenyev ◽

I.N. Borzov ◽

R.G. Nazmitdinov ◽

S. Åberg

Keyword(s):

Random Matrix ◽

Single Particle ◽

Ground State ◽

Matrix Theory ◽

Decay Rates ◽

Total Probability ◽

Phonon Coupling ◽

Skyrme Interaction ◽

Β Decay ◽

Gamow Teller

The β-decay rates of 60Ca have been studied within a microscopic model, which is based on the Skyrme interaction T45 to construct single-particle and phonon spaces. We observe a redistribution of the Gamow–Teller strength due to the phonon-phonon coupling, considered in the model. For 60Sc, the spin-parity of the ground state is found to be 1+. We predict that the half-life of 60Ca is 0.3 ms, while the total probability of the βxn emission is 6:1%. Additionally, the random matrix theory has been applied to analyze the statistical properties of the 1+ spectrum populated in the β-decay to elucidate the obtained results.

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Magnetic HexadecapoleγTransitions and Neutrino-Nuclear Responses in Medium-Heavy Nuclei

Advances in High Energy Physics ◽

10.1155/2016/8417598 ◽

2016 ◽

Vol 2016 ◽

pp. 1-8 ◽

Cited By ~ 8

Author(s):

Lotta Jokiniemi ◽

Jouni Suhonen ◽

Hiroyasu Ejiri

Keyword(s):

Nuclear Matrix ◽

Wave Functions ◽

Matrix Elements ◽

Heavy Nuclei ◽

Magnetic Quadrupole ◽

Order Of Magnitude ◽

Nuclear Responses ◽

Beta Decays ◽

Gamow Teller ◽

Phonon Model

Neutrino-nuclear responses in the form of squares of nuclear matrix elements, NMEs, are crucial for studies of neutrino-induced processes in nuclei. In this work we investigate magnetic hexadecapole (M4) NMEs in medium-heavy nuclei. The experimentally derived NMEs,MEXP(M4), deduced from observed M4γtransition half-lives are compared with the single-quasiparticle (QP) NMEs,MQP(M4), and the microscopic quasiparticle-phonon model (MQPM) NMEsMMQPM(M4). The experimentally derived M4 NMEs are found to be reduced by a coefficientk≈0.29with respect toMQP(M4) and byk≈0.33with respect toMMQPM(M4). The M4 NMEs are reduced a little by the quasiparticle-phonon correlations of the MQPM wave functions but mainly by other nucleonic and nonnucleonic correlations which are not explicitly included in the MQPM. The found reduction rates are of the same order of magnitude as those for magnetic quadrupoleγtransitions and Gamow-Teller (GT) and spin-dipole (SD)βtransitions. The impacts of the found reduction coefficients on the magnitudes of the NMEs involved in astroneutrino interactions and neutrinoless double beta decays are discussed.

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Gamow-Teller matrix elements from theB11(p,n)11C reaction atEp≊26MeV

Physical Review C ◽

10.1103/physrevc.31.1679 ◽

1985 ◽

Vol 31 (5) ◽

pp. 1679-1690 ◽

Cited By ~ 4

Author(s):

S. M. Grimes ◽

J. D. Anderson ◽

J. C. Davis ◽

R. H. Howell ◽

C. Wong ◽

...

Keyword(s):

Matrix Elements ◽

Gamow Teller

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Heavy-ion reactions as spin probes

Canadian Journal of Physics ◽

10.1139/p87-086 ◽

1987 ◽

Vol 65 (6) ◽

pp. 609-613 ◽

Cited By ~ 5

Author(s):

Sam M. Austin ◽

N. Anantaraman ◽

J. S. Winfield

Keyword(s):

Cross Sections ◽

Reaction Mechanisms ◽

Heavy Ion ◽

Spin Transfer ◽

Calibration Function ◽

Matrix Elements ◽

Heavy Ion Reactions ◽

One Step ◽

The One ◽

Gamow Teller

Heavy-ion reactions can be powerful probes for spin-transfer strength in nuclei, provided their reaction mechanism is simple so that a correlation can be established between cross sections and the relevant matrix elements. We discuss the desirable features of heavy-ion reactions in general and a series of tests of reaction mechanisms that have been carried out for two of the most favorable reactions; (6Li, 6He) and (12C, 12N). We establish that the (6Li, 6He) reaction is one-step in nature above 25 MeV∙nucleon−1 and establish a calibration function relating cross sections and Gamow–Teller matrix elements. We also find that the (12C, 12N) reaction is likely to be dominated by the one-step process above about 50 MeV∙nucleon−1.

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