At present, both vacuum oscillations as well as matter modified oscillations can explain the data of atmospheric neutrino experiments and the long baseline accelerator neutrino experiments equally well. Given the important role the matter effects play in the determination of CP violation in neutrino oscillations, it is imperative to establish the signal for matter effects unambiguously. In this work, we study the ability of ICAL at INO to make a distinction between vacuum oscillations and matter modified oscillations. We find that it is possible to make a $3\sigma$ discrimination in ten years, whether the atmospheric mass-squared difference is positive or negative.

中文翻译：

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大气中微子的物质与真空振荡

目前，真空振荡和物质修正振荡都能很好地解释大气中微子实验和长基线加速器中微子实验的数据。考虑到物质效应在中微子振荡中CP违规的确定中起着重要作用，因此必须为物质效应建立明确的信号。在这项工作中，我们研究了INO的ICAL区分真空振荡和物质修正振荡的能力。我们发现有可能使$3\sigma$ 判别十年间，大气质量平方差是正还是负。