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71.
Gamma ray source detection above 30 TeV is an encouraging approach for finding galactic cosmic ray sources. All sky survey for gamma ray sources using wide field of view detector is essential for population accumulation for various types of sources above 100 GeV. In order to target those goals, a large air shower particle detector array of 1 km^2 (the LHAASO project) at 4300 m a.s.l, is proposed, By adding two MagicⅡ- type telescopes in the array as proposed, LHAASO will be enhanced in source morphologic investigation power. The proposed array will be utilized also for energy spectrum measurement for individual cosmic ray species above 30 TeV. By re-configuring the wide field of view telescopes into fluorescence light detector array, the aperture of the detector array can be enlarged to cover an energy region above 100 PeV where the second knee is located. Cosmic ray spectrum and composition will be measured in order to transfer an energy scale to ultra high energy cosmic ray experiments. 相似文献
72.
Jung-Won Lee Seog-Tae Han Do-Young Byun Bon-Chul Koo Yong-Sun Park 《International Journal of Infrared and Millimeter Waves》2002,23(1):47-59
We have developed a 3 mm band receiver for SRAO. The receiver employs an Nb-based SIS junction in the mixer and operates at 85–115 GHz with single polarization. The receiver noise temperature is 40–50 K in DSB. It is equipped with an MPI-type filter for single-side band observations. We present the design, construction, and test results for individual components of the receiver optics, heterodyne system, and cryogenics. The receiver has been installed on the 6 m SRAO telescope and tested toward astronomical sources. The beam-measurement experiment suggests that the edge taper is smaller than the designed 12 dB. 相似文献
73.
以亚毫米波天文学的科研工作情况介绍在大学物理教学实践中的融入为例,针对时下大学教师教学工作和科研工作的双重角色,就如何将教师最新的科研工作进展引入到大学物理的教学中,引导学生对于物理学实效性的认识,激发学生对于大学物理的兴趣和热爱,进而促进大学物理的教学效果,用一些具体的实例进行了说明. 相似文献
74.
75.
宇宙黑暗时代是指宇宙大爆炸刚刚结束,第一代恒星和星系尚未形成的时期,这时的宇宙“鸿蒙未开”,蕴藏着宇宙起源阶段所遗留的大量宝贵信息。这一时期宇宙中性氢气体产生的21 cm信号为观测宇宙黑暗时代提供了探针,但这一信号现已红移到米波、十米波甚至百米波频段,在这一频段有其他天体特别是银河系产生的巨大前景辐射,在地球上的观测还受到地球电离层的吸收、折射以及多种电磁干扰,因此其观测具有极大的挑战性。利用月球背面或月球轨道进行观测具有优越的条件,可以避免电离层和电磁干扰对低频射电观测的影响。随着重返月球热潮的兴起,美国、欧洲、印度等国和中国都在积极酝酿月基天文特别是低频射电天文研究,打开低频电磁观测的新窗口,实现对宇宙黑暗时代和宇宙起源的探测。文章将介绍关于宇宙黑暗时代、宇宙黎明的研究进展以及利用月球开展低频射电天文观测的动向,并简要介绍中国提出的鸿蒙绕月卫星阵列计划。 相似文献
76.
太阳中微子及超新星中微子探测--2002年诺贝尔物理学奖成果评述 总被引:2,自引:0,他引:2
文章回顾了中微子天文学的诞生过程,着重介绍了2002年诺贝尔物理学奖获得者雷蒙特·戴维斯和小柴昌俊在观测太阳及超新星中微子方面的开创性贡献,扼要描述了这个领域的发展现状及前景,并简单探讨了历史给予人们的几点启发. 相似文献
77.
V. De Cosmo M. Petrizzelli 《International Journal of Infrared and Millimeter Waves》1983,4(4):541-548
The principle of Michelson spatial interferometer and considerations relating to its use in the FIR Astronomy are presented. A model of Michelson interferometer is proposed. 相似文献
78.
P. G. Ananthasubramanian Satoshi Yamamoto Tushar P. Prabhu 《International Journal of Infrared and Millimeter Waves》2002,23(2):227-243
We present 220 GHz (1.36 mm) measurements of zenith optical depth obtained to characterise the Indian Astronomical Observatory, Hanle (Ladakh, India) during the period from late December 1999 to early May 2000 and early October 2000 to September 2001. The data were sampled at an interval of 10 minutes. We describe the automated 220 GHz tipping radiometer used, its basic principle, operation, data acquisition method and data reduction scheme in detail. The 220 GHz opacity is found to be less than 0.06 for a significant fraction (40%) of the time during the winter months, indicating that Hanle is one of the good observing sites for submillimeter-wave astronomy. We make a preliminary correlation with the precipitable water vapour derived from surface relative humidity and air temperature measurements made during the same period with a weather station installed at the site. We also compare the Hanle site with other high-altitude sites like Mauna Kea and Atacama desert. 相似文献
79.
V. de Cosmo 《International Journal of Infrared and Millimeter Waves》1982,3(5):735-742
Measurements of atmospheric transmittance in the 7–10 cm–1 window were made for a period of 1 month, in the dry season (observation time about 300 h.) from the F. Duarte Observatory (3,600 m. above sea level) and from experimental station of Pico Espejo (4,765 m. above sea level). Correlation with the vertical water vapor density profile have been made.This work was financed by CONICIT, proyect PSI-1139 相似文献
80.
An equation is obtained for the pairing amplitude in a many-electron-proton system at finite temperature. It is noted that
under certain approximations it can be solved to give temperature-dependent discrete energy spectra. 相似文献