轻粒子发射时间随测量角的变化

利用小相对角关联方法测量了25MeV/u⁴⁰Ar+⁹³Nb反应中关联出射的轻粒子.通过与三体弹道模型的比较,从关联函数提取了轻粒子的发射时间.结果表明,轻粒子的发射时间随粒子能量的升高而降低,从低能的约600fm/c下降至高能的约50fm/c.将此数据与⁴⁰Ar+¹⁹⁷Au反应中的发射时间进行了比较,发现随着实验室系角度的增加,提取的轻粒子的发射时间变长,并认为其原因在于随发射角度的增加,前平衡发射成份越来越少,平衡发射成份增加.

Emission Time of Light Particles with Respect to Measurement Angle

Particle particle correlation functions at small correlation angle have been measured for 40Ar+ 93Nb collision at E 25MeV/u. Based on three body trajectory calculation the emission time scale of light particles has been extracted from correlation function of two particles at small relative momentum. The mean emission time scale decreases with increasing sum of the kinetic energies of the particles in a correlated pair. It decreases from about 500 fm/c for low energy particles to about 50 fm/c for high energy particles. And the extracted emission time scales from larger detection angle are longer than that extracted from the data obtained at small detection angle, which can be explained as the more particles emitted from equilibrated system.