Probing CPT violation with atmospheric neutrinos

Abstract

We investigate the recently suggested scheme of independent mass matrices for neutrinos and antineutrinos. Such a CPT violating scheme is able to account for all neutrino data with the three known flavors. For atmospheric neutrinos this means that it is possible to have different mass squared differences driving the oscillation for neutrinos and antineutrinos. We analyze the atmospheric and K2K data within the simplest scheme of two neutrino oscillation, neglecting electron neutrino oscillation. We find that the preferred region is close to the CPT conserving mass spectra. However the spectra with the antineutrino mass squared difference about or larger than 0.1 eV^2 and the neutrino mass squared difference about 2 \times 10^{-3} eV^2 is not significantly disfavored. In this parameter region the atmospheric data are independent of the antineutrino mass squared difference. Therefore no useful constraint can be put on CPT violation effects contributing to different masses for the neutrinos and antineutrinos.

8 pages, 2 figures. v3: Improved analysis, References added

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Cited by in corpus (8)

• Phenomenology with Massive Neutrinos
• Status of the CPT Violating Interpretations of the LSND Signal
• Extrinsic CPT Violation in Neutrino Oscillations in Matter
• MINOS and CPT-violating neutrinos
• Apparent CPT Violation in Neutrino Oscillation Experiments
• Neutral currents and tests of three-neutrino unitarity in long-baseline experiments
• Relation between CPT Violation in Neutrino masses and mixings
• Testing CPT Invariance with Neutrinos