CAREER Towards a GZK Neutrino Detector at the South Pole

该奖项由2009年《美国复苏和再投资法案》（Public Law 111-5）资助。宇宙射线发现近一百年后，中微子望远镜正在成为多信使方法的一个组成部分，以发现其仍然难以捉摸的起源。中微子是一种独特的天文信使，它可以为识别宇宙射线的来源及其产生的物理过程提供关键信息。中微子通过磁场保留它们的方向信息，并指向它们的来源。它们可以从其来源传播很长的距离而没有明显的衰减。从天体物理学来源观测中微子将是强子加速的明确证据，因为宇宙质子加速器预计会产生具有类似光度的宇宙射线、伽马射线和中微子。最近来自HiRES和AUGER的数据似乎支持“GZK截止”的存在，由于光生效应，宇宙射线光谱的修改，因此人们预计带电π衰变的超高能量中微子通量。由于极高能量的低通量，必须采用新的技术来构建足够大的成本有效的阵列，以获得在GZK能量下的统计上有意义的事件数。其中一种技术使用了Askaryan效应，其中无线电频率（RF）中的切伦科夫辐射用于测量中微子相互作用产生的簇射的能量和方向。该奖项提供资金，继续研究和开发探测器，以感测RF透明介质（如冰）中中微子诱导簇射的RF发射。 在南极安装这样一个射频传感器将大大提高冰立方阵列的通量灵敏度。这个项目的更广泛的影响包括参与公众宣传，努力扩大美国的影响。马里兰州的QuarkNet计划，以更大的观众和访问当地的高中谈论学生和教师的研究和经验，作为一个科学家。

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5).Nearly one hundred years after the discovery of cosmic rays, neutrino telescopes are becoming an integral part of a multi-messenger approach to discovering their still elusive origins. Neutrinos are unique astronomical messengers which may provide critical information in identifying sources of cosmic rays and the physics processes out of which they are born. Neutrinos retain their directional information through magnetic fields and point back to their source. They can travel long distances from their sources without significant attenuation. The observation of neutrinos from an astrophysical source would be unambiguous evidence for hadronic acceleration, since cosmic proton accelerators are expected to produce cosmic rays, gamma rays and neutrinos with similar luminosities. Recent data from HiRES and AUGER seem to support the existence of the "GZK cutoff", the modification of the cosmic ray spectrum due to the photoproduction effect and hence one expects a flux of ultra-high energy neutrinos from the charged pion decays.Because of the low flux at extremely high energies, novel techniques must be employed to build a cost effective array large enough to gain a statistically meaningful number of events at GZK energies. One such technique uses the Askaryan effect where the Cerenkov radiation in the radio frequencies (RF) is used to measure the energy and direction of the showers that result from the neutrino interactions. This award provides funds to continue research and development towards a detector to sense the RF emission from neutrino induced showers in RF transparent media such as ice. Such an RF sensor at the South Pole would significantly extend the flux sensitivity of the IceCube array. The Broader Impacts of this project include involvement in public outreach, working to expand U. Maryland's QuarkNet program to a larger audience and visiting local high schools to talk to students and teachers about research and experiences as a scientist.