精确的弹性散射角分布数据测量的轰击能量刚好高于库仑势垒的形状,可以显着不同或相同的预期的经典菲涅耳散射图案取决于结构的弹丸,目标或两者。例如18 O +184 W和16 O + 148,152 Sm,其中由于库仑核干涉而引起的卢瑟福散射的预期上升通过耦合到目标激发态而被阻尼,以及11 Li散射的极端情况,其中耦合到9 Li + n + n连续谱导致不能由任何标准光学模型参数集再现的弹性散射形状。最近获得的高质量的6He,11Li和11Be数据提供了耦合效应对弹性散射的影响的进一步例子。提出了强弹靶耦合效应的条件,特别强调了束靶装药组合足够大以产生强耦合效应的重要性。提出了几个测量,可以导致进一步了解强耦合效应的非弹性激发和核子转移近垒弹性散射。最后一个关于8B弹性散射的异常性质的说明,因为它具有或多或少的正常菲涅耳散射形状,而由于8B的非常低的破裂阈值,人们不会先验地期望这一点。11锂的特殊性质,因为它是预测,无论多远以上的库仑势垒的弹性散射测量,它的形状不会出现菲涅尔像而所有其他松散的结合核的弹性散射研究到目前为止,最终应该这样做,随着入射能量的增加,使8B和11锂真正的“异国情调”。
英文摘要:
Accurate elastic scattering angular distribution data measured at bombarding energies just above the Coulomb barrier have shapes that can markedly differ from or be the same as the expected classical Fresnel scattering pattern depending on the structure of the projectile, the target or both. Examples are given such as 18O + 184W and 16O + 148,152Sm where the expected rise above Rutherford scattering due to Coulomb-nuclear interference is damped by coupling to the target excited states, and the extreme case of 11Li scattering, where coupling to the 9Li + n + n continuum leads to an elastic scattering shape that cannot be reproduced by any standard optical model parameter set. The recent availability of high quality 6He, 11Li and 11Be data provides further examples of the influence that coupling effects can have on elastic scattering. Conditions for strong projectile-target coupling effects are presented with special emphasis on the importance of the beam-target charge combination being large enough to bring about the strong coupling effects. Several measurements are proposed that can lead to further understanding of strong coupling effects by both inelastic excitation and nucleon transfer on near-barrier elastic scattering. A final note on the anomalous nature of 8B elastic scattering is presented as it possesses a more or less normal Fresnel scattering shape whereas one would a priori not expect this due to the very low breakup threshold of 8B. The special nature of 11Li is presented as it is predicted that no matter how far above the Coulomb barrier the elastic scattering is measured, its shape will not appear as Fresnel like whereas the elastic scattering of all other loosely bound nuclei studied to date should eventually do so as the incident energy is increased, making both 8B and 11Li truly "exotic".
Study of 9Be+12C elastic scattering at energies near the Coulomb barrier
在这项工作中,角分布测量的弹性通道进行了9 Be +12 C反应在能量ELab=13.0,14.5,17.3,19.0和21.0 MeV,附近的库仑势垒。的数据进行了分析的框架内的双重折叠圣保罗潜力。实验的弹性散射角分布很好地描述了在所有测量的能量的前向角的光学势。然而,对于三个最高的能量,观察到增强的中间和向后的角度。这可以用弹性转移机制来解释。关键词:9 Be +12 C,弹性散射,圣保罗势。
Influence of vibrational excitation on surface diffuseness of inter-nuclear potential: study through heavy-ion quasi-elastic scattering at deep subbarrier energies
我们讨论了重离子反应中通道耦合在核间势表面性质中的作用。为此,我们分析了实验的准弹性截面的$^{12}$ C + $^{105,106}$ Pd和$^{13}$ C + $^{105,106}$ Pd系统使用耦合通道的方法,包括在目标核的振动激发。虽然早期的研究已经报道了一个可以忽略不计的影响振动激发的表面扩散参数的球形系统,我们发现一个显着的效果为C+Pd系统。我们的系统研究还揭示了传输耦合对表面扩散参数的影响。
Investigation of the role of neutron transfer in the fusion of 32,34S with 197Au,208Pb using quasi-elastic scattering
本文测量了32,34 S +197 Au和32,34 S +208 Pb系统在后向角处的准弹性散射激发函数。代表性的分布,敏感的低能量部分的融合屏障分布,已被提取的数据。在~(32),~(34)S与~(197)Au的熔合反应中,与~(197)Au的原子核结构有关的耦合在形成势垒分布的低能部分中起主导作用。与34 S +208 Pb的情况相比,32 S +208 Pb的势垒分布更宽,并且进一步延伸到较低的能量。这与中子拾取通道在32 S诱导反应中能量更有利的解释一致,因此更强烈地耦合到相对运动。这也可能是由于与34 S相比,32 S的集体性增加。
Employing $p+^{58}$Ni elastic scattering for determination of $K$-shell ionization cross section of $^{58}$Ni$^{19+}$ in collisions with hydrogen gas target at 95 MeV/u
提出了一种测量储存环中低电荷态离子与氢气靶碰撞的内壳层电离截面的新方法。该方法是基于一个众所周知的质子弹性散射的微分截面的核校准。本文测量了95 MeV/uPDMATHABMN Ni $^{19+}$离子与氢原子碰撞的1047(100)靶的$K$壳层电离截面。通过与实测电离截面的比较,验证了相对论电离修正程序(RICODE-M)的预测结果。
Measurement of $^{58}$Ni($p$, $p$)$^{58}$Ni elastic scattering at low momentum transfer by using the HIRFL-CSR heavy-ion storage ring
介绍了HIRFL-CSR重离子储存环上首次环内反应实验,即质子在稳定的$^{58}$ Ni核上的弹性散射。循环的$^{58}$ Ni $^{19+}$离子的能量为95 MeV/u与CSRe实验环中的内部氢气靶反复相互作用。用超高真空兼容硅条探测器测量了低能质子的弹性碰撞反冲。通过测量由于$^{58}$ Ni $^{19+}$ -H $_2$电离碰撞而产生的$^{58}$ Ni $^{19+}$射弹的K壳层X射线,归一化推导的微分截面。通过与实验截面的比较,发现在测量区域内的计算结果与理论计算结果吻合较好.我们的研究结果,使新的研究机会,光学模型潜力的研究外来核素通过使用环内反应装置在HIRFL-CSR设施。