Properties of nucleon resonances by means of a genetic algorithm

被引：28

作者：

Fernandez-Ramirez, C. ^{[1
,2
]}

Moya de Guerra, E. ^{[3
,4
]}

Udias, A. ^{[5
]}

Udias, J. M. ^{[3
]}

机构：

[1] MIT, Ctr Theoret Phys, Nucl Sci Lab, Cambridge, MA 02139 USA

[2] MIT, Dept Phys, Cambridge, MA 02139 USA

[3] Univ Complutense Madrid, Fac Ciencias Fis, Dept Fis Atom Mol & Nucl, Grp Fis Nucl, E-28040 Madrid, Spain

[4] CSIC, Inst Estructura Mat, E-28006 Madrid, Spain

[5] Univ Rey Juan Carlos, Escuela Super Ciencias Expt & Tecnol, Dept Estadist & Invest Operat, E-28943 Fuenlabrada, Spain

来源：

PHYSICAL REVIEW C | 2008年 / 77卷 / 06期

关键词：

D O I：

10.1103/PhysRevC.77.065212

中图分类号：

O57 [原子核物理学、高能物理学];

学科分类号：

070202 ;

摘要：

We present an optimization scheme that employs a genetic algorithm (GA) to determine the properties of low-lying nucleon excitations within a realistic photo-pion production model based upon an effective Lagrangian. We show that with this modern optimization technique it is possible to reliably assess the parameters of the resonances and the associated error bars as well as to identify weaknesses in the models. To illustrate the problems the optimization process may encounter, we provide results obtained for the nucleon resonances Delta(1230) and Delta(1700). The former can be easily isolated and thus has been studied in depth, while the latter is not as well known experimentally.

引用

页数：11

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