排序方式: 共有43条查询结果,搜索用时 46 毫秒
21.
利用imaging方法提取高能重离子碰撞中Core-Halo模型发射源的信息 总被引:1,自引:1,他引:0
根据对高斯源的检验, 引入两个π介子相对距离的均方根半径Rrmst来表示高能重离子碰撞中π介子发射源的空间尺寸。 利用imaging计算方法可以不依赖于源模型计算出相对距离的均方根半径。 对Core-Halo模型进行计算并与高斯拟合结果比较, 结果显示, 由于长寿命共振态衰变产生的π介子的贡献, 半径Rrmst显示出较大的π介子发射空间。 另外,对于π介子为混沌发射的情况, 通过imaging方法计算得到的π介子发射源的混沌性参量明显大于高斯拟合所得到的结果。 相似文献
22.
利用相对论量子分子动力学模型 RQMD,对 RHIC能区 s =2 0 0 AGe VAu+ Au中心碰撞进行了 2 π干涉学分析,对 HBT关联相干因子 λ的行为进行了研究 .研究表明 ,参数 λ一般小于理想混沌源时的值,这反映了源的部分相干特性外 ,还与源的膨胀和持续冻结有关 ,体现为 λ参数对粒子的冻结时间较为敏感.Using the dynamical transport model RQMD with a correlation after burner, the behavior of two pion HBT λ parameter is studied in Au+Au central collisions at RHIC energy s=200 A GeV. The λ parameter is found to be sensitive to the sequential freeze out in heavy ion collisions. 相似文献
23.
应用量子路径积分的方法,分析了高能重离子碰撞产生的高重子数密度粒子发射源的2K和2π干涉学(hanbury Brown Twiss,HBT关联)。利用相对论流体动力学描述源的演化,采用的状态方程包含QGP到强子相的一级相变和对强子气体的体积修正。在2π关联的计算中考虑了激发态粒子衰变和多重散射效应,并将其HBT关联半径和寿命与传统热冻结模型的结果进行了对比。计算表明,早期化学冻结产生的K介子的HBT关联半径比2π关联的HBT关联半径小。激发态粒子的衰变使HBT关联半径和寿命增加,而多重散射对HBT关联的结果几乎没有影响。Using quantum path integral formulae, we examined the two kaon and two pion Hanbury Brown Twiss (HBT) interferometry for the particle emitting source with high baryon density. The evolution of the source is described by relativistic hydrodynamics. We use an equation of state of first order transition from QGP to hadronic phase and consider a volume correction for the hadronic gas. The two pion HBT results with effects of excited particle decay and multiple scattering were investigated and compared with those for conventional thermal freeze out (TFO) model. We found that the two kaon HBT radius was smaller than those of the two pion interferometry. The particle decay increases the HBT radius and lifetime, while the effect of multiple scattering on HBT results can be neglected. 相似文献
24.
It is shown that resonance internal conversion offers a feasible tool for mastering nuclear processes with laser or synchrotron radiation. The physics of the process is discussed in detail in a historical aspect. Possible experimental application is shown in the case of the M1 70.6-keV transition in nuclei of 169 Yb. The nuclear transition rate in hydrogen-like ions of this nuclide can be enhanced by up to four orders of magnitude. 相似文献
25.
26.
27.
28.
29.
30.