ISSN:0094-243X    

DOI:10.1063/1.42037

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

We briefly report the development of the gas‐filled recoil‐type isotope separator (GARIS), which has recently been constructed at the RIKEN ring cyclotron facility. We then discuss the preliminary results of the (HI, &agr;xn) reactions as a possible new approach to synthesizing superheavy elements with GARIS.

ISSN:0094-243X    

DOI:10.1063/1.42003

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

By employing the kinematic separator VASSILISSA and the beams of20,22Ne,24,26Mg,40Ar and40Ca we studied 18 projectile‐target combinations leading to formation of compound nuclei with atomic numbers 83‐102 and obtained xn, pxn, and &agr;xn evaporation residues in the range of the projectile energy extending from the Coulomb barrier to the values corresponding to the compound nucleus excitation of about 100 MeV. The systematics is presented of the maximum xn reaction cross‐sections which are governed by the fissility of the reaction products. As a result, the values of macroscopic fission barriers were extracted for the neutron‐deficient nuclides in the range of Z=83–92 and N=104–134. These values are discussed in terms of contrasting with predictions of the rotating droplet model. Three isotopes,252,253,254102, were obtained as deexcitation products of the258102 compound nucleus formed by22Ne and26Mg projectiles. Some conclusions are drawn from these results about the possible use of22Ne and26Mg beams for synthesis of Z=106–110 nuclides having neutron numbers close to the predicted island of stability around N=162.

ISSN:0094-243X    

DOI:10.1063/1.42004

出版商:AIP    

年代:1992

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.42005

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

A new microscopic approach to the theory of dynamic correlation, ground state and collective excitations of many‐body systems is suggested. These dynamic and ground state properties are known as being interconnected and should be considered on the same base. A useful tool for this goal is a response function formalism. An exact functional equation for effective interaction and linear response function is obtained. The reduction method of the functional equation to a closed set of equations is given. In the simplest case the functional equation may be transformed into nonlinear integrodifferential equation. Few examples of many‐body systems are considered on the base of this equation. The developed method is applied to gas‐liquid phase transition, for evaluation of transport coefficients and collective excitation width.

ISSN:0094-243X    

DOI:10.1063/1.42006

出版商:AIP    

年代:1992

数据来源: AIP

摘要:

Transport theories, based on the quantum‐corrected Boltzmann equation, are widely used in the theory of heavy‐ion reactions. These theories are very successful in the analysis of the average dynamics of heavy‐ion reactions; they allow a microscopic treatment of the balance between mean‐field and two‐body collisions. Two limiting situations are studied: the scission of a nucleus and the characteristics of the nuclear sidewards flow. A study is then presented on the possibility to go beyond this average dynamics and to treat the dynamics of fluctuations.

ISSN:0094-243X    

DOI:10.1063/1.42007

出版商:AIP    

年代:1992

数据来源: AIP