基于自洽的RBUU输运理论研究介质内同位旋相关的NΔ→NΔ截面

The Calculation of the In-medium Isospin-dependent NΔ→NΔCross Section Based on the Self-consistent RBUU Theory

基于自洽的RBUU输运理论,研究了介质中同位旋相关的NΔ→NΔ散射截面。发现同位旋效应对重子的有效质量以及不同重子密度区的总NΔ弹性散射截面有着较为明显的影响。随着重子密度的增大,不同重子同位旋态之间的有效质量劈裂逐渐增大。在密度依赖的重子有效质量劈裂、耦合常数以及Born项中的σ-δ、σ-ρ、ω-δ、ω-ρ交换项的共同作用下,不同同位旋态分反应道的弹性散射截面呈现出了不同的密度依赖行为。总截面在低能区出现了明显的介质压低效应,高能区介质效应减弱。

Based on the self-consistent RBUU transport theory,the isospin-dependent in-medium N△→N△cross section is investigated.It is found that the isospin effect has a relatively obvious influence on the effective mass of baryons and the total N elastic cross section in different density regions.With the increase of baryon density,the effective mass splitting between different isospin states of baryons increases gradually.Under the joint effect of density-dependent baryon effective mass splitting,coupling constant,as well as Born terms such σ-δ,σ-ρ,ω-δ,ω-ρ,the elastic cross-sections of sub-channels with different isospin states exhibit different density-dependent behaviors.The total cross-section has an obvious reduction effect of medium in the low-energy region,and the medium effect is weakened in the high-energy region.