PRECISE MEASUREMENT OF ASTRO-NUCLEAR RECTION USING RECOIL MASS ANALYZER

使用反冲质量分析仪精确测量天体核反射

基本信息

批准号：
08404017
负责人：
SAGARA Kenshi
金额：
$ 22.59万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (A)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1999
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08404017/
关键词：
Astro-nuclear reaction Helium burning speed Supernovae Recoil mass analyzer Windowless gas target Gas stripper Accel-decal strong focus High-intensity C-beam パルスビーム星の流転

项目摘要

The astro-nuclear reaction of ィイD14ィエD1He+ィイD112ィエD1C->ィイD116ィエD1O+γ at EィイD2cmィエD2 = 300 keV plays a very important role in the supernovae and in the primordial nuclear synthesis. In spite of experimental efforts in the world over 30 years, no precise experimental data have been obtained yet due to the extremely small cross section. In the present study, we have developed new instruments and methods in order to precisely measure the reaction cross section in the range from EィイD2cmィエD2 = 3 MeV to 700 keV.We adopted the inverse kinematics method. The detection of the reaction product ィイD116ィエD1O in this method is more than 100 times more efficient than the γ-ray detection so far adopted in many experiments. To separate ィイD116ィエD1O coming out in forward angle and the ィイD112ィエD1C-beam, we developed a recoil mass separator that is composed of one electric deflector, two magnetic deflectors, four quadrupole magnets, and four auxiliary multipole magnets.We also developed a new blow-in type windowless gas target which was found to have enough gas-confining power and to produce ideal gas distribution. Satisfactory target thickness is obtained by the blow-in gas target together with the gas cooling system.We succeeded in strong-focus beam acceleration by the new accel-decel method using Kyushu University tandem accelerator. In this success, we showed that the large tandem accelerator can be transformed to a small tandem with a little modification. we also succeeded in the development of a large aperture gas stripper. By the two successes, a low-energy beam necessary for the astro-nuclear experiment in creased more than 100 times in intensity. Moreover we have succeeded in the production of the pulse beam to be used for the background reduction.After the above developments, we have started the preliminary experiment for the measurement of the ィイD14ィエD1He+ィイD112ィエD1C->ィイD116ィエD1+γ reaction cross section.

D14 D1HE+D112 D1C-> D116 D1O+γ的Astro-核反应在D2CM D2 = 300 keV在超新星和原始核合成中起着非常重要的作用。尽管全球30年以来的实验努力，但由于极小的横截面，尚未获得精确的实验数据。在本研究中，我们开发了新的工具和方法，以精确测量从EI D2CM D2 = 3 MEV到700 KEV的范围内的反应横截面。我们采用了逆运动学方法。在这种方法中，在此方法中检测反应产物EI D116 D1O的效率是迄今为止在许多实验中采用的γ射线检测效率的100倍以上。为了将EI D116 D1O分离为前角和EI D112 D1C光束，我们开发了一个由一个电力偏转器，两个电磁偏转器，四个四极杆磁铁和四个辅助多重磁铁组成的，我们还开发了一个新的无易于窗口的窗户，该窗户的无效气体可生产出足够的天然气配置，从而使无效的发电机配置为理想的发电机。通过吹入气体目标以及气体冷却系统获得令人满意的目标厚度。我们使用Kyushu University串联加速器成功地通过新的加速度二级方法来成功进行强焦束加速度。这一成功，我们表明，大型串联加速器可以转换为一个小的串联，并进行了一些修改。我们还成功地开发了大型的气管脱衣舞娘。通过这两个成功，在强度超过100倍的Astro核实验中，必需的低能光束。此外，我们已经成功地生产了用于降低背景的脉冲梁。上述发展后，我们开始了初步实验，以测量EI D14 D1HE+II D112 D112 D1C-> II D116 D116 D116 D1+γ+γ反应截面。