摘要:

The proton decay of a deformed nucleus which undergoes shape modifications during the emission process is investigated through the use of the TDSE approach developed recently. Qualitative and illustrative preliminary calculations are presented for high-energy excited states in58Cu.Tunneling probabilities, decay rates and angular distributions of proton emission are calculated and their dependency upon the (time-dependent) deformation of the potential is investigated. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306012

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

Using Green’s function techniques, we derive expressions for the width of a proton decaying state in spherical and deformed nuclei. We show that the proton decay widths calculated by the “exact” expressions of Maglione &etal; are equivalent to the distorted wave expressions of Bugrov &etal;, and that of A˚berg &etal; in the spherical case. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306013

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

It is shown that the multiparticle theory of proton radioactivity (MTPR), based on the integral formulas for proton widths, has sufficiently high accuracy and totality for description of deep subbarrier proton decay of nuclei. The theoretical scheme of calculation for proton widths of odd-odd deformed nuclei is created. The connection of fine proton spectrum structure with types of proton orbit in 141Ho141Hois analyzed. It is shown that nuclear deformation parameters, found for investigation of proton decay of deformed odd-even and odd-odd nuclei and predicted by some systematics are the same. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306014

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

To model the decay of a quasibound state we use the modified two-potential approach introduced by Gurvitz and Kalbermann [1,2]. This method has proved itself useful in the past for calculating the decay width and the energy shift of an isolated quasistationary state [5]. We follow the same approach in order to propagate the wave-packet in time with the ultimate goal of extracting the momentum-distribution of emitted particles. The advantage of the method is that it provides the time-dependent wave function in a simple semi-analytic form. We intend to apply this method to the modeling of metastable states for which no direct integration of the time-dependent Schro¨dinger equation is available today. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306015

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

The time-dependent approach to calculate half-lives for proton-emitting nuclei is reviewed. Doubts about the practicability of this new method are eliminated by showing that it directly leads to the main observable (the average decay rate), that the result does not depend on the prescription used to prepare the initial state or to define the nuclear border and that the method can be applied to low-lying as well as to highly excited states. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306016

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

Beta-delayed proton emission was first observed thirty-six years ago. At the time, its unique signature opened a window onto a new world of exotic nuclei: on-line isotope separation was not yet available to isolate newly produced nuclei, but a readily separable decay mode was a fine alternative. In the first two decades after its discovery, beta-delayed proton decay was a rich source of spectroscopic information on nuclei far from stability, yielding everything from analog states and atomic masses to level densities and excited-state lifetimes in the femtosecond region. However, with the advent of more sophisticated methods for the production and isolation of exotic nuclei, the importance of beta-delayed protons as an identifier of new nuclei effectively disappeared. Nevertheless, the potential spectroscopic value of the process remains undiminished. In fact, as the number of known beta-decaying nuclei steadily increases, beta-delayed proton emission is seen to be a widely occurring phenomenon. Its usefulness needs to be rediscovered. This paper presents an overview of beta-delayed proton emission, its occurrence, its usefulness and its potential for the future. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306017

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

The rp-process occurs in a hot hydrogen-rich stellar environment. Its trajectory passes through the most proton-rich nuclides in the periodic table. It has long been thought to be responsible for synthesizing at least the light p-process nuclides. Thus these nuclides can provide signatures for rp-process nucleosynthesis. Difficulties with various rp-process scenarios often focus on92,94Moand96,98Rup-nuclides, as their anomalously large abundances are difficult to produce in any model of nucleosynthesis. However, it now appears that they might be produced in the rp-process resulting from accretion onto a neutron star. If the rp-process does synthesize these nuclides, &bgr;-delayed proton emission might well resolve some of the difficulties made evident by the model calculations. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306018

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

Results on103–107Instrength function measurements are presented. The domination of the core(&pgr;g9/2)8over the valence proton decay is confirmed. Contribution of a&bgr;pdecay channel to the total &bgr; strength function of 0.5&percent; and 43&percent; for102Inand100In,respectively, is expected based on theBGTsystematics, available&bgr;pspectra and statistical model calculations. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306019

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

The combination of projectile fragmentation reactions and in-flight separation has proved to be a powerful tool to produce nuclei at the limits of stability. Decay studies of very neutron-deficient projectile fragments led to the discovery of several new &bgr;-delayed particle emitters. Basic principles of the method are described and various aspects of extracting interesting spectroscopic information from &bgr;-delayed particle studies at projectile fragment separators are discussed. ©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306020

出版商:AIP    

年代:1900

数据来源: AIP

摘要:

©2000 American Institute of Physics.

ISSN:0094-243X    

DOI:10.1063/1.1306021

出版商:AIP    

年代:1900

数据来源: AIP