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14Be 库仑破裂实验准备. 哈尔滨工程大学 RIBLL 合作组会议 @ 兰州 2013.08 宋玉收. 内容提要. 背景 事件产生与探测器建模 靶厚与 PID 讨论 实验事件预估 总结. 库仑破裂研究丰中子核. M. Labiche et. al, prl86.600.2001. 库仑破裂应用. R rms (exp.) →. S 2n (exp.) and. 14Be 库仑破裂研究现状 实验数据有限,存在矛盾 数据与 11Li 、 6He 不同. S 2n =0.9MeV. S 2n =1.34MeV. 库仑破裂优势
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14Be 库仑破裂实验准备 哈尔滨工程大学 RIBLL合作组会议@兰州 2013.08 宋玉收
内容提要 • 背景 • 事件产生与探测器建模 • 靶厚与PID讨论 • 实验事件预估 • 总结
库仑破裂研究丰中子核 M. Labiche et. al, prl86.600.2001 • 库仑破裂应用
Rrms (exp.) → S2n (exp.) and • 14Be库仑破裂研究现状 • 实验数据有限,存在矛盾 • 数据与11Li、6He不同 S2n=0.9MeV S2n=1.34MeV
库仑破裂优势 • 针对滴线核束流弱,截面大; • 外围碰撞,产物前向运动,可以前向角布置探测器; 实验装置示意图
Nuclear reaction in G4 • G4 nuclear reaction models • Binary Cascade • Abrasion & Ablation • QMD • EMD • Not feasible for our problem
Kinematics Pb Inelastic scattering Dissociation 14Be 14Be* 12Be 14Be* 2n S2n 12Be+n+n 14Be
12Be kinematic information 2n kinematic information
14Be before EMD • Reaction position • Momentum direction • Kinetic energy P z
Position distribution M. Labiche et. al, prl86.600.2001 570mg/cm2 ~500 m
r Z
Target thickness M. Labiche et. al, prl86.600.2001: 0.503 mm
Influence on PID 12Be Time of Flight 14Be
According to EMD cross section: (1)The purity of 12Be with the PID cut is 80%=54898/(54898+13660) (2)12Be loss rate because of E-E Cut is ignorable
Pb Target 1mm Particle Identification becomes more difficult
S2n 14Be* 12Be+n+n 14Be
PRELIMINARY Red: spectrum set Black: spectrum reconstructed Pb Target 0.5mm Red: spectrum set Black: spectrum reconstructed Pb Target 1mm
26.0/hour*100hour=2600 20Ne(80AMeV, 100enA) 200enA 的18O 作为入射初级束,3500um 的9Be 作为初级靶,降能器为2000um 的Al,分离提纯后的14Be,能量为35AMeV,能量展宽约8MeV(~1.6%),流强约为20 pps.
Summary • M. Labiche et. Al (prl86.600.2001) chose the target with a thickness of 570mg/cm2 ~500 m; • According to our simulation 1mm is still a feasible thickness; • Thicker target will crack the reconstructed spectrum; • To be done: • Real three-body kinematic calculation; • Create GEANT4 Physics process to handle EMD reaction of 14Be on Pb target; • Considering optical process of neutron wall and CsI; • Considering neutron wall in more detail;