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Interpreting the LSND anomaly: sterile neutrinos or CPT-violation or...?

Alessandro Strumia
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Abstract

We first study how sterile neutrinos can fit the 5sigma bar-nu_mu --> bar-nu_e LSND anomaly: 2+2 solutions are strongly disfavoured by solar and atmospheric data, while 3+1 solutions can still give a poor fit (for a specific range of oscillation parameters, to be tested by MiniBooNE). If instead MiniBoone will find no nu_mu --> nu_e signal, we will have a hint for CPT violation. Already now, unlike sterile neutrinos, CPT-violating neutrino masses can nicely accomodate all safe and unsafe data. We study how much CPT must be conserved according to atmospheric and K2K data and list which CPT-violating signals could be discovered by forthcoming solar and long-baseline experiments.

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Alessandro Strumia. 2003-02-20. Interpreting the LSND anomaly: sterile neutrinos or CPT-violation or...?. https://doi.org/10.1016/s0370-2693(02)02042-7

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