Study of High Energy Cosmic Rays in the Tibetan Highlands

青藏高原高能宇宙线研究

• 批准号: 07044064
• 负责人: YUDA Toshinori
• 金额: $ 10.75万
• 依托单位: The Univ.of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for international Scientific Research
• 财政年份: 1995
• 资助国家: 日本
• 起止时间: 1995 至 1997
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-07044064/
• 关键词: Tibet; Yangbajing; Air shower array; Celestial Gamma-ray source; Sun shadow; Burst detector; Primary proton component; Knee region; 一次宇宙線

In 1995, our air shower array, which has been operating at Yangbajing (4300 above sea level in Tibet as a collaboration experiment between Japan and China, was enlarged (the number of detectors increased from 65 to 221), and we are searching for 10 TeV celestial gamma-ray point sources and also studying the primary cosmic rays in ultra-high energy region. This is a unique air shower array capable of detecting 10 TeV cosmic rays with sufficient accuracy and we have already obtained a lot of important scientific results. Using the data obtained from this experiment, we obtained the primary energy spectrum in the energy region from 4x10^{14} to 2x10^{16} eV,showing a gradual steepening at around 2x10^{15} eV.This result will give a strong constraint to the mechanism of high energy cosmic ray acceleration. We also examined a yearly time variation of the Sun's shadow by cosmic rays in the period during 1990 through 1993 (corresponding to near maximum or declining phase of the solar activity cycle, and found that there exists a strong correlation between the movement of the sun's shadow and the phase of the solar activity. Eventually, our observation will obtain new information about the solar and interplanetary magnetic fields.In 1996, we also constructed a high density air shower array (detector separation is 7.5m) and a detector complex of emulsion chambers and burst counters with the total area of 80 m^2 near the center of the old array. The former is to search for supra TeV gammma ray sources and the latter is to observe the primary proton spectrum around the knee region and will be continued until summer of 1999. A preliminary results will be obtained around the end of this year since the data are now under analysis.

1995年，我们在扬巴吉（Yangbajing）运行的空气淋浴阵列（在西藏的海平面高达4300个，作为日本和中国之间的协作实验，探测器的数量从65人增加到221个），我们正在搜索10 Tev天体gamma-ray点源，还可以在Ultra rays rays rays rays nor tewign tewign the Is Is tewign tewign tewir tewir tewignighigh rays tevertion。宇宙射线具有足够的准确性，我们已经获得了许多重要的科学结果，我们从4x10^{14}到2x10^{16} eV中获得了能量区域的主要能量谱，显示了逐渐降至2x10^{15} ev的速度。在1990年至1993年期间，宇宙射线对太阳阴影的年度时间变化（对应于太阳能活动周期的接近最大或下降阶段，发现太阳阴影的运动与太阳能活动的阶段之间存在很强的相关性。最终，我们的观察结果将获得有关太阳能和星际磁场的新信息。在1996年，我们还构建了一个高密度的空气淋浴阵列（检测器分离为75m），并在旧阵列附近的乳液室和爆裂柜子的检测器配合物和爆裂柜子的检测器配合物。前者是搜索Supra Tev Gammma射线源，后者是观察膝盖区域周围的主要质子光谱，并将继续持续到1999年夏天。由于数据正在分析中，因此今年年底将在今年年底获得初步结果。

项目成果

M.Amenomori et al.: "Shadowing of cosmic rays by the Sun near maximum or at the decling phase of solar activity" The Astrophysical Journal,. (in press). (1996)

M.Amenomori 等人：“太阳活动接近最大值或衰退阶段时太阳对宇宙射线的阴影”《天体物理学杂志》。

C.S.Zhang, K.Kasahara and T.Yuda: "Neural network approach to obtain the primary proton flux at the knee from a hybrid-experiment of EC and AS array in Tibet" NIM. Vol.A376. 263-270 (1996)

C.S.Zhang、K.Kasahara 和 T.Yuda：“通过西藏 EC 和 AS 阵列混合实验获取膝部初级质子通量的神经网络方法”NIM。

M.Amenomori et al.: "Shadowing of cosmic rays by the Sun near maximum or at the declining phase of solar activity" ApJ. Vol.464. 954-958 (1996)

M.Amenomori 等人：“太阳活动接近最大值或衰退阶段时太阳对宇宙射线的阴影”ApJ。

M.Amenomori et al.: "Search for 10 TeV burst-like events coincident with the BATSE bursts using the Tibet air shower array" Astronomy and Astrophysics,. (in press). (1996)

M.Amenomori 等人：“使用西藏空气簇射阵列搜索与 BATSE 爆发同时发生的 10 TeV 类爆发事件”《天文学与天体物理学》。

M.Amenomori et al.: "The cosmic ray energy spectrum between 10^<14.5>0^<16.3> eV covering the “Knee"region" The Astrophysical Journal,. 426(in press). (1996)

M.Amenomori 等人：“覆盖“膝盖”区域的 10^<14.5>0^<16.3> eV 之间的宇宙射线能量谱”《天体物理学杂志》，426（出版中）。