Recent Results in the Development of a Global Medium-energy Nucleon-nucleus Optical-model Potential

Recent Results in the Development of a Global Medium-energy Nucleon-nucleus Optical-model Potential PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Initial results are presented for the determination of a global medium-energy nucleon-nucleus phenomenological optical-model potential using a relativistic Schroedinger representation. The starting point for this work is the global phenomenological optical-model potential of Schwandt)ital et al.), which is based on measured elastic scattering cross sections and analyzing power for polarized protons ranging from 80 to 180 MeV. This potential is optimally modified to reproduce experimental proton reaction cross sections as a function of energy, while allowing only minimal deterioration in the fits to the elastic cross sections and analyzing powers. Further modifications in the absorptive potential were found necessary to extrapolate the modified potential to higher energies. The final potential is converted to a neutron-nucleus potential by use of standard Lane model assumptions and by accounting approximately for the Coulomb correction. Comparisons of measured and calculated proton reaction and neutron total cross sections are presented for 27Al, 56Fe, and 2°8Pb. Medium-energy optical-model potentials for complex projectiles are briefly discussed in an appendix. 7 refs., 20 figs.

Recent Results in the Development of a Global Medium-energy Nucleon-nucleus Optical-model Potential

Recent Results in the Development of a Global Medium-energy Nucleon-nucleus Optical-model Potential PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Initial results are presented for the determination of a global medium-energy nucleon-nucleus phenomenological optical-model potential using a relativistic Schroedinger representation. The starting point for this work is the global phenomenological optical-model potential of Schwandt)ital et al.), which is based on measured elastic scattering cross sections and analyzing power for polarized protons ranging from 80 to 180 MeV. This potential is optimally modified to reproduce experimental proton reaction cross sections as a function of energy, while allowing only minimal deterioration in the fits to the elastic cross sections and analyzing powers. Further modifications in the absorptive potential were found necessary to extrapolate the modified potential to higher energies. The final potential is converted to a neutron-nucleus potential by use of standard Lane model assumptions and by accounting approximately for the Coulomb correction. Comparisons of measured and calculated proton reaction and neutron total cross sections are presented for 27Al, 56Fe, and 2°8Pb. Medium-energy optical-model potentials for complex projectiles are briefly discussed in an appendix. 7 refs., 20 figs.

Development of Global Medium-energy Nucleon-nucleus Optical Model Potentials

Development of Global Medium-energy Nucleon-nucleus Optical Model Potentials PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 6

Get Book Here

Book Description
The authors report on the development of new global optical model potentials for nucleon-nucleus scattering at medium energies. Using both Schroedinger and Dirac scattering formalisms, the goal is to construct a physically realistic optical potential describing nucleon-nucleus elastic scattering observables for a projectile energy range of (perhaps) 20 meV to (perhaps) 2 GeV and a target mass range of 16 to 209, excluding regions of strong nuclear deformation. They use a phenomenological approach guided by conclusions from recent microscopic studies. The experimental database consists largely of proton-nucleus elastic differential cross sections, analyzing powers, spin-rotation functions, and total reaction cross sections, and neutron-nucleus total cross sections. They will use this database in a nonlinear least-squares adjustment of optical model parameters in both relativistic equivalent Schroedinger (including relativistic kinematics) and Dirac (second-order reduction) formalisms. Isospin will be introduced through the standard Lane model and a relativistic generalization of that model.

Energy Research Abstracts

Energy Research Abstracts PDF Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 840

Get Book Here

Book Description


Publications of Los Alamos Research

Publications of Los Alamos Research PDF Author: Los Alamos National Laboratory
Publisher:
ISBN:
Category : Research
Languages : en
Pages : 276

Get Book Here

Book Description


Advanced Monte Carlo for Radiation Physics, Particle Transport Simulation and Applications

Advanced Monte Carlo for Radiation Physics, Particle Transport Simulation and Applications PDF Author: Andreas Kling
Publisher: Springer Science & Business Media
ISBN: 3642182119
Category : Science
Languages : en
Pages : 1200

Get Book Here

Book Description
This book focuses on the state of the art of Monte Carlo methods in radiation physics and particle transport simulation and applications. Special attention is paid to algorithm development for modeling, and the analysis of experiments and measurements in a variety of fields.

An Energy-Dependent, Lane-Model, Nucleon-Nucleus Optical Potential

An Energy-Dependent, Lane-Model, Nucleon-Nucleus Optical Potential PDF Author: D. M. Patterson
Publisher:
ISBN:
Category :
Languages : en
Pages : 9

Get Book Here

Book Description
A global, energy-dependent, Lane-model, nucleon-nucleus optical potential has been determined by fitting (p, n)-IAS angular distributions between 25 and 45 MeV while maintaining the fit obtained by Becchetti and Greenlees to proton elastic-scattering data over a wide mass and energy range, thus firmly establishing the essential validity of the Lane model for nucleon-nucleus optical potentials.

Analytic Optical Potentials for Nucleon-nucleus Nucleus-nucleus Collisions Involving Light and Medium Nuclei

Analytic Optical Potentials for Nucleon-nucleus Nucleus-nucleus Collisions Involving Light and Medium Nuclei PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 28

Get Book Here

Book Description


Proceedings of a Specialists' Meeting on Preequilibrium Nuclear Reactions, Semmering, Austria, 10th-12th February 1988

Proceedings of a Specialists' Meeting on Preequilibrium Nuclear Reactions, Semmering, Austria, 10th-12th February 1988 PDF Author: Brigitte Strohmaier
Publisher:
ISBN:
Category : Nuclear physics
Languages : en
Pages : 334

Get Book Here

Book Description


ERDA Energy Research Abstracts

ERDA Energy Research Abstracts PDF Author:
Publisher:
ISBN:
Category : Power resources
Languages : en
Pages : 676

Get Book Here

Book Description


Use of Services for Family Planning and Infertility, United States, 1982

Use of Services for Family Planning and Infertility, United States, 1982 PDF Author: Gerry E. Hendershot
Publisher:
ISBN: 9780840602220
Category : Birth control
Languages : en
Pages : 982

Get Book Here

Book Description
The 1982 statistics on the use of family planning and infertility services presented in this report are preliminary results from Cycle III of the National Survey of Family Growth (NSFG), conducted by the National Center for Health Statistics. Data were collected through personal interviews with a multistage area probability sample of 7969 women aged 15-44. A detailed series of questions was asked to obtain relatively complete estimates of the extent and type of family planning services received. Statistics on family planning services are limited to women who were able to conceive 3 years before the interview date. Overall, 79% of currently mrried nonsterile women reported using some type of family planning service during the previous 3 years. There were no statistically significant differences between white (79%), black (75%) or Hispanic (77%) wives, or between the 2 income groups. The 1982 survey questions were more comprehensive than those of earlier cycles of the survey. The annual rate of visits for family planning services in 1982 was 1077 visits /1000 women. Teenagers had the highest annual visit rate (1581/1000) of any age group for all sources of family planning services combined. Visit rates declined sharply with age from 1447 at ages 15-24 to 479 at ages 35-44. Similar declines with age also were found in the visit rates for white and black women separately. Nevertheless, the annual visit rate for black women (1334/1000) was significantly higher than that for white women (1033). The highest overall visit rate was for black women 15-19 years of age (1867/1000). Nearly 2/3 of all family planning visits were to private medical sources. Teenagers of all races had higher family planning service visit rates to clinics than to private medical sources, as did black women age 15-24. White women age 20 and older had higher visit rates to private medical services than to clinics. Never married women had higher visit rates to clinics than currently or formerly married women. Data were also collected in 1982 on use of medical services for infertility by women who had difficulty in conceiving or carrying a pregnancy to term. About 1 million ever married women had 1 or more infertility visits in the 12 months before the interview. During the 3 years before interview, about 1.9 million women had infertility visits. For all ever married women, as well as for white and black women separately, infertility services were more likely to be secured from private medical sources than from clinics. The survey design, reliability of the estimates and the terms used are explained in the technical notes.