文摘:天体物理中微子使我们能够获得人造加速器无法达到的能量和基线，为新的物理现象提供了独特的探测。这篇论文旨在解决目前在高能宇宙中使用天体物理中微子搜索超越标准模型(BSM)物理所面临的挑战，特别是在味道测量和与暗物质的联系的背景下。天体物理学中微子的新物理学研究需要了解标准中微子源作为先决条件，这仍然是不明确的。我们首先使用冰立方9年的数据对天体物理中微子源进行多波长搜索。我们从明亮的活动星系核(AGN)中发现了中微子发射的迹象，这进一步支持了最近关于中微子发射发生在AGN核心附近的说法。接下来我们将注意力转向BSM搜索。对天体物理通量的精确测量为BSM物理学提供了确凿的证据。这需要精确测量中微子的分数。然而，tau的识别被证明是当前一代天文台的主要障碍。我们首先引入Taurunner来解决天体物理中微子味道测量的问题，Taurunner是一种模拟工具，可以准确地模拟tau中微子的传播，包括以前被忽视的影响，如tau轻子能量损失和物质去极化。 We show that better modeling of tau neutrino propagation improves IceCube transient point-source sensitivities by more than an order of magnitude at EeV energies, and diffuse flux sensitivities by a factor of two. Second, we use this software to model IceCube counterparts to anomalous events reported by the ANITA experiment. After performing an analysis using IceCube data, we show that all Standard Model explanations are ruled out. Looking ahead to the future of flavor measurements, we also present a study that predicts the production of tau neutrinos via the propagation of electron and muon neutrinos in Earth, finding an irreducible but quantifiable background to next-generation tau neutrino observatories. Finally, we attempt to address the field's shared ignorance of the origin of neutrino and dark matter masses by exploring potential connections between the two. Specifically, we present an analysis of dark matter annihilation and decay to neutrinos. We obtain limits from MeV to ZeV masses using more than a dozen neutrino experiments. Notably, using recent data from the SuperKamiokande experiment, we place the first-ever limit on dark matter annihilation that reaches the thermal relic abundance in the neutrino sector, challenging notions that studies with neutrinos cannot be sensitive enough to make strong claims about the nature of dark matter.