ISSN:0003-3804    

DOI:10.1002/andp.19885000402

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractThe isentropic expansion of a blob of nuclear matter towards the two‐phase instability region is studied by considering two extreme conditions: the instantaneous development of the phase transition and the spinodal decomposition. We show that the experimentally observed entropy values of light clusters give evidence for the onset of a liquid‐gas phase transition in heavy ion and proton induced reactions, but to be more conclusive the disassembly of relatively cold nuclear systems has experimentally to be investigated in more det

ISSN:0003-3804    

DOI:10.1002/andp.19885000403

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractA model for black hole collapse and evaporation in which the black hole is supposed to be an excited state of one of the Planck black holes pervading the structure of spacetime is discussed. By assuming a Coleman‐Weinberg gravitational effective potential for a scalar field inside the collapse matter, it is shown that the black hole state cannot be attained neither through bubble tunneling nor by the rolling down of the fiel

ISSN:0003-3804    

DOI:10.1002/andp.19885000404

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractThe O5R Monte Carlo neutron transport Code had been used to calculate the neutron albedo for neutrons reflected from plane and curved concrete shields. The present calculations were performed to investigate the fast‐neutron albedo in case of ordinary concrete shield, in order to perform comparative studies with the case of neutron reflection against a flat wall. The calculations were performed for three different neutron source energies of 1 MeV, 5 MeV and 15 MeV and at neutron incident angles of 5°, 30°, 45°, 60° and 90° and for surfaces with different curvatures (flat, 100, 50, 20 and 5 cm).The results obtained reveal that there will be an appreciable error on using the flat wall albedo value in the case of duct penetration calculations. The error was assumed to be due to the neglection of the curvature effect as well as to the improper choice of the neutron incident

ISSN:0003-3804    

DOI:10.1002/andp.19885000405

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractIn this paper we present exact solutions of the Klein‐Gordon and the Dirac equations in different configurations of an electromagnetic field, which are characteristic for free‐electron laser‐type gauges. In the case of motion of a charge scalar particle in standing wave an energy spectrum is studied. For the motion of an electron in a so‐called wiggler magnetic field a spinor wave function is proved to be obtainable. An undulator field configuration with propagating wave is treat

ISSN:0003-3804    

DOI:10.1002/andp.19885000406

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractA velocity dependent effective potential ofs‐ andp‐wave interaction denoted by VG2 has been applied to calculate the parameters of nuclear matter. Using this potential, the binding energy of a group of double closed shell nuclei is calculated according to the shell model. Also, the binding energy of12C and16O is calculated assuming Brink's model and using the VG2 interaction together with the potential deduced by Arickx et al. Reasonable agreement with experimental data is obtai

ISSN:0003-3804    

DOI:10.1002/andp.19885000407

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractWith the help of various sum rules we look into the spin‐isospin excitations in nuclei within a framework of the quark model. The effect of Pauli correlations is explicitly taken care of. In agreement with the experiments we find negligible amount of M1 strength in heavy nuclei. This is explained in terms of the Fermi gas mode

ISSN:0003-3804    

DOI:10.1002/andp.19885000408

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractGauge fields of Poincaré translations define particular nongravitation structure on a space‐time, which can be treated as sui generis space‐time dislocations. Their source is the canonical energy‐momentum tensor of matter, and these dislocations can introduce some corrections to standard values of gravitation effects, e. g. the Yukawa type corrections to the Newtonian gravitation pot

ISSN:0003-3804    

DOI:10.1002/andp.19885000409

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

摘要:

AbstractThe possibility to detect nonconventional scalar, pseudoscalar or tensor interactions (SPT) in the angular distribution of pions produced coherently in neutrino nucleus reactions is reexamined. It is found that the angular distribution does not differ qualitatively from a corresponding distribution arising from conventional VA interactions unless the energy of the outgoing pion is restricted. Even then SPT interactions are likely to be overshadowed by transverse VA interactions which can mimic the former at finite although small momentum transferQ2.

ISSN:0003-3804    

DOI:10.1002/andp.19885000410

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY

ISSN:0003-3804    

DOI:10.1002/andp.19885000411

出版商:WILEY‐VCH Verlag    

年代:1988

数据来源: WILEY