PaperPanorama

Nuclear Theory·nucl-th

Friday·December 17, 2021

8 papers4 primary·4 cross-listed

  1. 01

    Comprehensive study of muon-catalyzed nuclear reaction processes in the molecule

    M. Kamimura · Y. Kino · T. Yamashita

    Muon catalyzed fusion (CF) has recently regained considerable research interest owing to several new developments and applications. In this regard, we have performed a comprehensive study of the most important fusion reaction, namely +++17.6 MeV or ++17.6 MeV. The coupled-channels Schrödinger equation for the reaction is thus solved, satisfying the boundary condition for the muonic molecule as the initial state and the outgoing channel with the - wave. We employ the - and -channel coupled three-body model. All the - and - potentials, and the - channel-coupling nonlocal tensor potential are chosen to reproduce the observed low-energy astrophysical -factor of the reaction +++17.6 MeV, as well as the total cross section of the + reaction. The resultant fusion rate is 1.15x10 s. Substituting the obtained total wave function into the matrix, we have calculated absolute values of the fusion rates going to the bound and continuum states of the outgoing - pair. We then derived the initial - sticking probability =0.857%, which is 7% smaller than the literature values (0.91-0.93%), and can explain the recent observations (2001) at high D-T densities. We also calculate the absolute values for the momentum and energy spectra of the emitted muon. The most important result is that the peak energy is 1.1 keV although the mean energy is 9.5 keV. This is an essential result for the ongoing experimental project to realize the generation of an ultra-slow negative muon beam by utilizing the CF for various applications e.g., a scanning negative muon microscope and an injection source for the muon collider.

    nucl-thnucl-exphysics.atom-phphysics.plasm-phPRC(2023)·12 citations
  2. 02

    Pairing strength in the relativistic mean-field theory determined from fission barrier heights of actinide nuclei and verified by pairing rotation and binding energies

    Taiki Kouno · Chikako Ishizuka · Tsunenori Inakura · Satoshi Chiba

    We have studied strength in the BCS pairing force, used as a residual interaction to the relativistic mean-field to reproduce the height of the inner fission barriers for actinide nuclei. It was found that increasing the pairing strength by about 13% makes reproduce the inner fission barriers better over a wide range of actinide nuclei. This result was verified by using the moment-of-inertia of pairing rotational energy, which was introduced to avoid mean-field and odd-mass effects in the pairing interaction to deduce purely the pairing strength. The pairing interaction thus determined could simultaneously improve the description of the binding energy of heavy nuclei as well. As a result, a consistent picture among inner fission barrier, binding energy, and pairing moment of inertia could be obtained in terms of the relativistic mean-field + BCS theory for a broad region of the actinide nuclei.

    nucl-thnucl-exPTEP(2022)·4 citations
  3. 03

    System dependence of away-side broadening and -clustering light nuclei structure effect in dihadron azimuthal correlations

    Yuan-Zhe Wang🇨🇳 · Song Zhang🇨🇳 · Yu-Gang Ma🇨🇳

    A collision system scan involving -clustered C and O is studied by using a multiphase transport model for central collisions at TeV. Background subtracted away-side dihadron azimuthal correlation is performed via the zero yield at minimum (ZYAM) method from raw signals, and the quantitative parameters, such as RMS width and Kurtosis, seem nicely follow the law of the system size if the nucleus has the normal Woods-Saxon nucleon distribution. However, for -clustering light nuclei, specifically for C and O, the RMS width and Kurtosis of away-side azimuthal correlation are deviated from the baseline of law. In addition, the momentum dependence of away-side broadening parameters is also presented. The results show that there is a distinction in away-side broadening parameters of dihadron correlation function between the Woods-Saxon distribution and the -clustered structures, which sheds light on that the collision system scan for dihadron azimuthal correlation as a potential probe to distinguish -clustered nuclei.

    nucl-thhep-phnucl-exPLB(2022)·35 citations
  4. 04

    Surface effects on hydrodynamic evolution

    Sanatan Digal🇮🇳 · P. S. Saumia🇷🇺

    We study the effect of surface tension of the phase boundary in the dynamics of an expanding fluid. A fluid at local thermal equilibrium, but has a slowly varying temperature profile, like the plasma formed in heavy ion collisions, will have rapidly varying order parameter field at the edge of the plasma where the temperature falls below the transition temperature. In the case where the free energy admits a first order transition, the gradient energy of this field will act as surface tension. We couple hydrodynamics and order parameter field evolutions to study the effect of this surface in the expansion of the plasma. We see that the surface slows down the expansion which reflects in the development of radial flow and momentum anisotropy.

    nucl-thhep-ph0 citations

Affiliations

first authorsco-authorsvia INSPIRE