Gamma-Ray Astrophysics with Upgraded VERITAS

使用升级版 VERITAS 进行伽马射线天体物理学

• 批准号: 249686-2013
• 负责人: Hanna, David
• 金额: $ 19.67万
• 依托单位: McGill University
• 依托单位国家: 加拿大
• 项目类别: Subatomic Physics Envelope - Project
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=570688
• 关键词: Gamma; Ray; Astrophysics; Upgraded; VERITAS

This application is for funding to support continued McGill participation in the VERITAS gamma-ray astronomy project. VERITAS is one of three major detectors world-wide that study astrophysical gamma rays with energies greater than 100 GeV. It consists of an array of four large telescopes designed to detect the ultraviolet and blue Cherenkov light emitted by energetic electrons and positrons produced when high-energy astrophysical gamma rays interact in the upper atmosphere. Such gamma rays are produced in extreme environments such as supernova remnants and active galactic nuclei. There may also be gamma rays which come from more exotic origins such as annihilation of dark-matter particles in the cores of galaxies or from evaporation of primordial black holes. As such, they could provide information about particle physics at energies beyond what can be probed at earth-bound accelerators. The VERITAS array, located in southern Arizona, was completed in 2007 and began four-telescope observations in September of that year. So far we have detected over 40 sources of astrophysical gamma rays, in eight classes. Over half of these are new discoveries; the remainder are confirmations. We have participated in multi-wavelength campaigns with data from X-ray, optical and radio telescopes, as well as the Fermi Gamma-ray Space Telescope which covers the gamma-ray energy range just below that where VERITAS is sensitive. The VERITAS detector has met and exceeded all design specifications but we continue to improve it. In 2009 we moved one of the four telescpes to optimize the array layout and in the summer of 2012 we replaced all photomultipliers in the telescope cameras with newly available high-quantum-efficiency models further increasing our sensitivity. A new trigger has been installed to allow running at lower energy threshold and improved reconstruction and background-rejection techniques have been incorporated into the analysis stream. Based on the output from the previous years we expect a period of high scientific productivity and many exciting new results.

该申请旨在资助麦吉尔继续参与VERITAS伽马射线天文学项目。VERITAS是全球研究能量大于100 GeV的天体物理伽马射线的三大探测器之一。它由四个大型望远镜组成的阵列，旨在探测高能天体物理伽马射线在高层大气相互作用时产生的高能电子和正电子发射的紫外线和蓝色切伦科夫光。这种伽马射线产生于极端环境，如超新星遗迹和活动星系核。还可能有来自更奇异来源的伽马射线，例如星系核心暗物质粒子的湮灭或原始黑洞的蒸发。因此，它们可以提供能量超过地球加速器所能探测的粒子物理学信息。位于亚利桑那州南部的VERITAS阵列于2007年完成，并于当年9月开始进行四台望远镜的观测。到目前为止，我们已经探测到超过40个天体物理伽马射线源，分为八类。其中一半以上是新发现;其余的是确认。我们利用X射线、光学和射电望远镜以及费米伽马射线空间望远镜提供的数据参加了多波长活动，费米伽马射线空间望远镜涵盖的伽马射线能量范围刚好低于VERITAS的敏感范围。VERITAS探测器已经达到并超过了所有的设计规格，但我们仍在继续改进。2009年，我们移动了四个望远镜中的一个，以优化阵列布局，2012年夏天，我们将望远镜相机中的所有光电倍增管更换为新的高量子效率型号，进一步提高了我们的灵敏度。安装了一个新的触发器，允许在较低的能量阈值下运行，并将改进的重建和背景抑制技术纳入分析流。根据前几年的产出，我们预计会有一个高科学生产力和许多令人兴奋的新成果的时期。