论文标题
用于测量积雪的原位校准系统的仿真研究和无线电中微子检测器的索引索引轮廓
Simulation study for an in-situ calibration system for the measurement of the snow accumulation and the index-of-refraction profile for radio neutrino detectors
论文作者
论文摘要
可以通过利用冰中的Askaryan效应来获得对超高能中微子的敏感性（$ e> 10^{17} $ eV），在冰中，质子中微子相互作用诱导的粒子级联反应会产生相干的无线电发射，而天线可以通过天线进行。由于近地表冰的特性在上部$ \ Mathcal {o} $（1亿）内迅速变化，因此需要对冰属性的良好理解来重建中微子性质。特别是，连续监测积雪（会改变天线的深度）和索引 - 拨款$ n（z）$概况对于准确确定中微子的方向和能量至关重要。我们提出了一个原位校准系统，该系统通过测量直接和反射信号（d'N'R）之间的时间差（d'N'R）之间的时间差，可通过两个无线电发射器扩展无线电探测器站。我们在当前和未来的冰射线探测器的所有三个地点上确定了两个发射机的最佳位置：格陵兰，摩尔湾和南极。对于南极，我们发现可以分辨率为3毫米的积雪$ΔH$以及指数$ n（z）$ profile $α$和$ z_0 $的参数，$ 0.04％和0.14％的精度，与$ n（z）相比，它构成了超过10倍的精度，从而构成了10倍的改进。此外，由于该技术基于信号传播时间的测量，因此我们与密度转换为折射索引的转换不束缚。我们量化了这些冰不确定性对中微子顶点，方向和能量重建的影响，并发现校准装置测量了冰的特性，以使其具有足够的精度，从而具有可忽略的影响。
Sensitivity to ultra-high-energy neutrinos ($E>10^{17}$eV) can be obtained cost-efficiently by exploiting the Askaryan effect in ice, where a particle cascade induced by the neutrino interaction produces coherent radio emission that can be picked up by antennas. As the near-surface ice properties change rapidly within the upper $\mathcal{O}$(100m), a good understanding of the ice properties is required to reconstruct the neutrino properties. In particular, continuous monitoring of the snow accumulation (which changes the depth of the antennas) and the index-of-refraction $n(z)$ profile are crucial for an accurate determination of the neutrino's direction and energy. We present an in-situ calibration system that extends the radio detector station with two radio emitters to continuously monitor the firn properties within the upper 40m by measuring the time differences between direct and reflected (off the surface) signals (D'n'R). We determine the optimal positions of two transmitters at all three sites of current and future in-ice radio detectors: Greenland, Moore's Bay, and the South Pole. For the South Pole we find that the snow accumulation $Δh$ can be measured with a resolution of 3mm and the parameters of an exponential $n(z)$ profile $α$ and $z_0$ with 0.04% and 0.14% precision respectively, which constitutes an improvement of more than a factor of 10 as compared to the inference of the $n(z)$ profile from density measurements. Additionally, as this technique is based on the measurement of the signal propagation times we are not bound to the conversion of density to index-of-refraction. We quantify the impact of these ice uncertainties on the reconstruction of the neutrino vertex, direction, and energy and find that the calibration device measures the ice properties to sufficient precision to have negligible influence.
