The sources of ultra-high energy (UHE) cosmic rays, which can have energies up to 10^20 eV, remain a mystery. UHE neutrinos may provide important clues to understanding the nature of cosmic-ray sources. ARIANNA aims to detect UHE neutrinos via radio (Askaryan) emission from particle showers when a neutrino interacts with ice, which is an efficient method for neutrinos with energies between 10^16 eV and 10^20 eV. The ARIANNA radio detectors are located in Antarctic ice just beneath the surface. Neutrino observation requires that radio pulses propagate to the antennas at the surface with minimum distortion by the ice and firn medium. Using the residual hole from the South Pole Ice Core Project, radio pulses were emitted from a transmitter located up to 1.7 km below the snow surface. By measuring these signals with an ARIANNA surface station, the angular and polarization reconstruction abilities are quantified, which are required to measure the direction of the neutrino. After deconvolving the raw signals for the detector response and attenuation from propagation through the ice, the signal pulses show no significant distortion and agree with a reference measurement of the emitter made in an anechoic chamber. Furthermore, the signal pulses reveal no significant birefringence for our tested geometry of mostly vertical ice propagation. The origin of the transmitted radio pulse was measured with an angular resolution of 0.37 degrees indicating that the neutrino direction can be determined with good precision if the polarization of the radio-pulse can be well determined. In the present study we obtained a resolution of the polarization vector of 2.7 degrees. Neither measurement show a significant offset relative to expectation.

中文翻译：

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探索南极 ARIANNA 探测器的角和偏振重建

超高能 (UHE) 宇宙射线的来源（其能量可达 10^20 eV）仍然是个谜。UHE中微子可能为理解宇宙射线源的性质提供重要线索。ARIANNA 旨在通过中微子与冰相互作用时粒子簇射的无线电 (Askaryan) 发射检测 UHE 中微子，这是一种有效的方法，用于检测能量在 10^16 eV 和 10^20 eV 之间的中微子。ARIANNA 无线电探测器位于南极冰层正下方。中微子观测要求无线电脉冲传播到表面的天线，而冰和冰介质的失真最小。使用南极冰芯项目的剩余孔洞，无线电脉冲从位于雪面以下 1.7 公里处的发射器发射。通过使用 ARIANNA 地面站测量这些信号，角度和极化重建能力被量化，这是测量中微子方向所必需的。在对探测器响应的原始信号和通过冰传播的衰减进行解卷积后，信号脉冲没有显示出明显的失真，并且与在消声室中对发射器进行的参考测量一致。此外，对于我们测试的主要是垂直冰传播的几何形状，信号脉冲没有显示出明显的双折射。以 0.37 度的角分辨率测量发射的无线电脉冲的起源，这表明如果可以很好地确定无线电脉冲的极化，则可以非常精确地确定中微子的方向。在本研究中，我们获得了 2.7 度的偏振矢量分辨率。