PaperPanorama

Nuclear Theory·nucl-th

Friday·November 22, 2019

8 papers6 primary·2 cross-listed

  1. 07

    [Submitted on 20 Nov 2019] (cross-list from cond-mat.dis-nn)

    Experimental validation of the theoretical prediction for the optical matrix

    A.M. Martínez-Argüello · V. Domínguez-Rocha · R.A. Méndez-Sánchez · M. Martínez-Mares

    Scattering of waves is omnipresent in nature in systems with sizes varying from to m. Within this 40 orders of magnitude, in a great number of systems, the scattering can be separated in an averaged response that crosses rapidly the scattering region and a fluctuating delayed response. This fact is the basis of the optical model; the averaged response, represented by the optical matrix , is composed with the fluctuating part that can be taken as a random matrix. Although the optical model was developed more than 60 years ago, a theoretical prediction for the optical matrix was obtained until very recently. The validity of such prediction is experimentally demonstrated here. This is done studying the scattering of torsional waves in a quasi-1D elastic system in which a locally periodic system is built; the distribution of the scattering matrix is calculated completely free of parameters. In contradistinction to all previous works, in microwaves and in elasticity, in which the value of is obtained from the experiment, here the theoretical prediction is used to compare with the experiment. Numerical simulations show that the theoretical value is still valid when strong disorder is present. Several applications of the theoretical expression for the optical matrix in other areas of physics are proposed. Possible extensions of this work are also discussed.

    Comments:
    7pages, 5 figures
    Subjects:
    cond-mat.dis-nn (cond-mat.dis-nn); cond-mat.mtrl-sci (cond-mat.mtrl-sci); nlin.CD (nlin.CD); Nuclear Theory (nucl-th)
    arXiv:
    1911.09205 [pdf]
    PRB(2020)·0 citations
  2. 08

    [Submitted on 21 Nov 2019] (cross-list from nucl-ex)

    Axial-vector weak coupling at medium momentum for astro neutrinos and double beta decays

    Hiroyasu Ejiri🇯🇵

    Neutrino nuclear responses associated with medium momentum transfer of q=20-80 MeV for astro neutrinos and double beta decays were studied by using charge exchange reactions on Te128 and Te130. Gamow-Teller and spin dipole nuclear matrix elements are found to be reduced with respect to the pnQRPA matrix elements by the coefficient of around 0.35. The reduction is discussed in terms of the quenching of axial vector coupling (g_A).

    Subjects:
    Nuclear Experiment (nucl-ex); Nuclear Theory (nucl-th)
    arXiv:
    1911.09269 [pdf]
    J.Phys.G(2019)·10 citations

Affiliations

first authorsco-authorsvia INSPIRE