Measurement of high energy cosmic rays originated from Vela SNR

初等宇宙射线起源的确立是宇宙射线物理学中最重要的课题。为了得到最终的答案，最重要的是测量初级宇宙射线的各向异性。然而，各向异性的数量级预计为0.1%。然后，必须以足够的精度进行观察。这是为了观测大气深度周围风淋室的最大发展，即采用高空风淋室阵列。本文通过对Chacaltaya山（5200m a.s. . l.）的空气雨的观测，测量了船帆座（Vela SNR）发射的宇宙射线的各向异性。船帆座是x射线和伽马射线区域最活跃的天体之一。叙述了2001年设备安装后的观测情况。对其进行了持续的观测和分析，初步结果在2001年德国汉堡国际宇宙射线会议和日本物理学会会议上发表。观测结果总结如下：(1)观测到来自银盘的初级宇宙射线的增强。(2)在星系纵向区域附近，从220°到260°的增强程度约为0.3%。(3)我们对宇宙射线在星系中传播的蒙特卡罗模拟表明，如果船帆座的信噪比是在10万年前产生的，如果信噪比与太阳系的距离约为250 pc，那么观测结果可以很好地解释从信噪比发射的宇宙射线。由于目前接受的值分别是1万年和500pc，最近的ROSAT结果显示距离约为250pc，并且在10万年前发生了另一次爆炸。(3)我们对宇宙射线在星系中传播的蒙特卡罗模拟表明，如果船帆座的信噪比是在10万年前产生的，如果信噪比与太阳系的距离约为250 pc，那么观测结果可以很好地解释从信噪比发射的宇宙射线。由于目前接受的值分别是1万年和500pc，最近的ROSAT结果显示距离约为250pc，并且在10万年前发生了另一次爆炸。少

The establishment of the origin of primary cosmic rays is most important theme in cosmic ray physics. To get the final answer it is most important to measure the anisotropy of primary cosmic rays. However, the order of the magnitude of the anisotropy is expected to be 0.1%. Then the observation must be done with sufficient accuracy. This is achieved so to make an observation around the atmospheric depths of air shower maximum developments, that is, with a high altitude air shower array.In this research, we observed air showers at Mt. Chacaltaya (5,200m a. s. l.) to measure the anisotropy due to the cosmic rays emitted from Vela SNR, which is one of the most active astronomical objects in X-and gamma-ray regions.We stated the observation from 2001 after the installment of the equipments. The observation and analyzes were made continuously and preliminary results were presented in the international conference of cosmic rays in Hamburg, Germany 2001 and the meetings of the Physical Societ … More y of Japan.The observed result is summarized as the follows :(1)The enhancement of primary cosmic rays from the galactic disk is observed.(2)The degree of the enhancement around the galactic longitudinal region from 220 to 260 degree is about 0.3%.(3)Our Monte-Carlo simulation on the cosmic rays propagation in the galaxy shows that if Vela SNR is made at 100,000 years ago if the distance of the SNR from the solar system is about 250 pc, the observed result is well explained due to the cosmic rays emitted from the SNR. Since the present accepted values are 10,000 years and 500 pc, respectively, the resent ROSAT results show that the distance is about 250pc and there is another explosion at 100,000 years ago.(3)Our Monte-Carlo simulation on the cosmic rays propagation in the galaxy shows that if Vela SNR is made at 100,000 years ago if the distance of the SNR from the solar system is about 250 pc, the observed result is well explained due to the cosmic rays emitted from the SNR. Since the present accepted values are 10,000 years and 500 pc, respectively, the resent ROSAT results show that the distance is about 250pc and there is another explosion at 100,000 years ago. Less