High-precision inverse potentials for neutron-proton scattering using piece-wise smooth Morse functions  

作　　者：Ayushi Awasthi Arushi Sharma Ishwar Kant O.S.K.S.Sastri 

机构地区：[1]Department of Physics and Astronomical Science,Central University of Himachal Pradesh,Dharmshala,176215,India

出　　处：《Chinese Physics C》2024年第10期201-213,共13页中国物理C（英文版）

基　　金：Support provided by Department of Science and Technology(DST),Government of India vide Grant No.DST/INSPIRE Fellowship/2020/IF200538。

摘　　要：The aim of this study is to construct inverse potentials for various ℓ-channels of neutron-proton scattering using a piece-wise smooth Morse function as a reference.The phase equations for single-channel states and the coupled equations of multi-channel scattering are solved numerically using the 5^(th) order Runge-kutta method.We employ a piece-wise smooth reference potential comprising three Morse functions as the initial input.Leveraging a machine learning-based genetic algorithm,we optimize the model parameters to minimize the mean-squared error between simulated and anticipated phase shifts.Our approach yields inverse potentials for both single and multichannel scattering,achieving convergence to a mean-squared error≤10^(-3).The resulting scattering lengths"a_(0)"and effective ranges"r"for ^(3)S_(1) and ^(1)S_(0) states,expressed as[a_(0),r],are found to be[5.445(5.424),1.770(1.760)]and[–23.741(–23.749),2.63(2.81)],respectively;these values are in excellent agreement with experimental ones.Furthermore,the calculated total scattering cross-sections are highly consistent with their experimental counterparts,having a percentage error of less than 1%.This computational approach can be easily extended to obtain interaction potentials for charged particle scattering.

关 键 词：inverse potentials neutron-proton scattering piece-wise smooth Morse function phase function method reference potential approach genetic algorithm 

分 类 号：O571[理学—粒子物理与原子核物理]