权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Precise measurement of ultra-heavy nuclei in cosmic rays

宇宙射线中超重核的精确测量

基本信息

批准号：
13440080
负责人：
HASEBE Nobuyuki
金额：
$ 9.15万
依托单位：
Waseda University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2001
资助国家：
日本
起止时间：
2001 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-13440080/
关键词：
galactic cosmic ray trans-iron nuclei isotopic compositeon mass resolution large area silicon detector solid-state track detector TSUBASA satellite TIGER balloon experiment 宇宙線同位体弁別宇宙線の起源元素合成粒子加速機構粒子伝播機構 Cosmic ray Heavv

项目摘要

The trans-iron cosmic rays were observed by balloon experiments using solid-state track detectors and satellite observation of Ariel-6,HEAO-3 and Trek. The measurement accuracies, however, were unsatisfactory because of low charge resolutions of their detectors. Moreover, these are no observations of trans-iron isotope compositions in cosmic rays. The measurement of these compositions gives crucial constrains on a cosmic ray source and a chemical evolution of the galaxy, including their acceleration and propagation processes.The basic developments of detectors for trans-iron isotopes and ultra-heavy nuclei up to actinides were performed for future planning of these observations in cosmic rays. Large silicon detectors with high uniformity and the solid-state track detectors such as CR-39 with a high mass resolution of 0.20 amu in rms for iron nuclei were developed in this study. Moreover, in order to establish the analyzing method of cosmic rays, we participated TIGER team of balloon observation. The collision mean-free-paths of Si, Fe and Ni in the atmosphere were obtained with high accuracy with the measurements of energy dependence of those nuclei for total charge-changing cross-sections. Furthermore, the study of high energy phenomena in the solar atmosphere and the interplanetary space is a miniature version occurring in the galaxy and gives an important clue to study dynamical astrophysical processes. In order to understand these phenomena, heavy ions in the radiation belts and from solar particle events were observed using the data from HIT instrument onboard TSUBASA satellite. It is found that the flux ration of helium isotopes, 3He/4He is greatly enhanced in the radiation belt by 3-4 orders of magnitude as compared with the solar abundance ratio. The origin of 3He in radiation belt is still under study.

利用固体轨道探测器和Ariel-6、HEAO-3和Trek卫星观测的气球实验观测了跨铁宇宙射线。然而，由于其探测器的电荷分辨率较低，测量精度并不令人满意。此外，这些都没有观测到宇宙射线中的反式铁同位素组成。对这些成分的测量为宇宙射线源和星系的化学演化提供了关键的约束，包括它们的加速和传播过程。反式铁同位素和超重核直至锕系元素的探测器的基本发展是为了将来在宇宙射线中进行这些观测的计划。本研究开发了具有高均匀性的大型硅探测器和铁核质量分辨率高达0.20 amu的CR-39等固态径迹探测器。此外，为了建立宇宙射线的分析方法，我们参加了TIGER气球观测小组。通过测量Si、Fe和Ni在大气中的总电荷变化截面的能量依赖关系，获得了它们在大气中的碰撞平均自由程。此外，研究太阳大气和行星际空间中的高能现象是发生在星系中的微缩版，为研究天体物理动力学过程提供了重要线索。为了了解这些现象，利用TSUBASA卫星上的HIT仪器观测了辐射带和太阳粒子事件中的重离子。与太阳丰度比相比，辐射带中氦同位素3He/4He的通量比显著提高了3-4个数量级。辐射带中3He的来源仍在研究中。