Signals of R-parity violating supersymmetry in neutrino scattering at muon storage rings

Abstract

Neutrino oscillation signals at muon storage rings can be faked by supersymmetric (SUSY) interactions in an R-parity violating scenario. We investigate the τ -appearance signals for both long-baseline and near-site experiments, and conclude that the latter is of great use in distinguishing between oscillation and SUSY effects. On the other hand, SUSY can cause a manifold increase in the event rate for wrong-sign muons at a long-baseline setting, thereby providing us with signatures of new physics. The increasingly strong empirical indications of neutrino oscillations from the solar and atmospheric neutrino deficits [1] have emphasized the need for their independent confirmation in accelerator and reactor experiments. One of the actively discussed possibilities in this connection is a muon storage ring [2, 3] which can act as an intense source of collimated neutrinos impinging upon a fixed target. A μ (μ+) beam can thus produce both νμ (ν̄μ) and ν̄e (νe), thereby providing an opportunity to test both νe-νμ and νμ-ντ oscillations which are the favoured solutions for the two types of anomalies mentioned above. In the simplest extensions of the standard model, non-degenerate masses for the different neutrino species (and consequent mixing among them) can account for the oscillation phenomena. Considering, for example, the atmospheric νμ deficit, the SuperKamiokande (SK) results [1] strongly suggest νμ-ντ oscillation with ∆m 2 ≃ 10−3 − 10−2 eV 2 and sin 2θ ≃ 1. Such oscillation was earlier indicated by the Irving-Michigan-Brookhaven and Kamiokande collaborations, and has been also supported more recently by the SOUDAN-II [4] and MACRO [5] experiments. At a muon storage ring, one therefore expects a certain fraction of the νμ’s to oscillate into ντ , depending on the energy and the baseline length. Interaction of these ντ ’s with the target material will produce τ -leptons, the detection of which may, in the simplest E-mail: anindya@mri.ernet.in E-mail: raj@mri.ernet.in E-mail: biswarup@mri.ernet.in E-mail: mpoonam@mri.ernet.in

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Cite this paper

@inproceedings{Datta2000SignalsOR, title={Signals of R-parity violating supersymmetry in neutrino scattering at muon storage rings}, author={Anindya Datta and Raj Gandhi and Biswarup Mukhopadhyaya and Poonam Mehta}, year={2000} }