RUI: Investigations of the Gamma Ray Detection Capabilitiesof Low Energy Threshold Air Cherenkov Telescopes

伽玛射线天文学涵盖了非常广泛的能量范围，从几兆电子伏到超过一百电子伏。目前，20gev到200gev的临界能量区域无法观测到。在较低的能量下，伽马射线是用卫星上的探测器观测到的。在更高能量的地面探测器间接观测伽马射线，从天体物理的来源，通过探测切伦科夫光从电磁级联发射，这是由伽马射线通过地球大气层的结果。卫星探测器观测到的大量辐射源高达约20gev。能量阈值为200gev的地面探测器只能看到很少的伽马射线源。因此，中间区域是非常有趣的，下一代陆基空气切伦科夫探测器的目标是降低进入该区域的能量阈值。设计低能量阈值空气切伦科夫探测器的关键是能够模拟探测器对伽马射线诱导的空气阵雨的灵敏度。KASCADE仿真系统是为模拟空气切伦科夫探测器系统而开发的一系列计算机程序。KASCADE系统模拟了由入射伽马射线和入射质子引起的空气阵雨，生成了相关切伦科夫光的模型，并测试了特定望远镜设计对这些空气阵雨的响应。该系统可用于研究望远镜的能量阈值、通量灵敏度和伽马射线对质子的分辨能力。研究计划的长期目标是开发一种低能量阈值空气切伦科夫探测器的设计。该研究项目还将对KASCADE系统进行改进，包括开发一种更“用户友好”的系统形式，以分发给感兴趣的用户，对与伽马射线探测和辨别有关的切伦科夫图像的特性进行几项小规模研究，并对现有和拟议的空中切伦科夫系统进行建模。用于探测20 GeV到200 GeV区域伽马射线的低能量阈值地面空气切伦科夫望远镜将打开一扇通往宇宙的新窗口。如果有可能发展这项技术，一个低能地面望远镜可以在不到十年的时间内设计，建造和运行。相比之下，下一代卫星探测器的开发时间更长，对伽马射线的探测不太可能达到高于50 GeV的能量。

9500231 Kertzman Gamma ray astronomy encompasses a very broad range of energies, from a few MeV to over one hundred TeV. Currently, the critical energy region from 20 GeV to 200 GeV is inaccessible to observation. At lower energies, gamma rays are observed with satellite borne detectors. At higher energies ground based detectors indirectly observe gamma rays, from astrophysical sources, by detecting the Cherenkov light emitted from the electromagnetic cascade which results from the passage of a gamma ray through the Earth's atmosphere. Satellite borne detectors observe an abundance of sources up to approximately 20 GeV. Groundbased detectors, with energy thresholds of 200 GeV see very few gamma ray sources. The intermediate region is therefore of extreme interest, and the goal of the next generation of ground based air Cherenkov detectors is to lower the energy threshold into this region. Essential to the process of designing a low energy threshold air Cherenkov detector is the ability to model the detectors sensitivity to gamma ray induced air showers. The KASCADE simulation system is a series of computer programs developed to model air Cherenkov detector systems. The KASCADE system simulates the air showers due to both incident gamma rays and incident protons, generates a model of the associated Cherenkov light, and tests the response of a specific telescope design to these air showers. The system can be used to study the energy threshold, flux sensitivity, and gamma ray versus proton discrimination power, of a telescope. The long term goal of the research program is to develop a design for a low energy threshold air Cherenkov detector. The research program will also make improvements to the KASCADE system, including developing a more "user friendly" form of the system to distribute to interested users, undertake several small scale studies of the properties of Cherenkov images related to the detection and discrimination of gamma rays, and model cur rently existing and proposed air Cherenkov systems. A low energy threshold ground based air Cherenkov telescope for detecting gamma rays in the region from 20 GeV to 200 GeV will open a new window to the universe. If it is possible to develop this technique, a low energy ground based telescope could be designed, built and operating in less than a decade. In contrast, the next generation of satellite borne detectors has a longer development timescale, and detection of gamma rays is unlikely to reach energies higher than 50 GeV.