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Simultaneous B and L Violation: New Signatures from RPV-SUSY

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 نشر من قبل Bob Zheng
 تاريخ النشر 2014
  مجال البحث
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Studies of R-parity violating (RPV) supersymmetry typically assume that nucleon stability is protected by approximate baryon number (B) or lepton number (L) conservation. We present a new class of RPV models that violate B and L simultaneously (BLRPV), without inducing rapid nucleon decay. These models feature an approximate $Z_2^e times Z_2^mu times Z_2^tau$ flavor symmetry, which forbids 2-body nucleon decay and ensures that flavor antisymmetric $L L E^c$ couplings are the only non-negligible L-violating operators. Nucleons are predicted to decay through $N rightarrow K e mu u$ and $n rightarrow e mu u$; the resulting bounds on RPV couplings are rather mild. Novel collider phenomenology arises because the superpartners can decay through both L-violating and B-violating couplings. This can lead to, for example, final states with high jet multiplicity and multiple leptons of different flavor, or a spectrum in which depending on the superpartner, either B or L violating decays dominate. BLRPV can also provide a natural setting for displaced $tilde{ u} rightarrow mu e$ decays, which evade many existing collider searches for RPV supersymmetry.

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