We present a search for the decays of B0 mesons into a final state containing a Λ baryon and missing energy. These results are obtained from a 711fb−1 data sample that contains 772×10^6 BB¯ pairs and was collected near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider. We use events in which one B meson is fully reconstructed in a hadronic decay mode and require the remainder of the event to consist of only a single Λ. No evidence for these decays is found and we set 90% confidence level upper limits on the branching fractions in the range 2.1-3.8×10^−5. This measurement provides the world's most restrictive limits, with implications for baryogenesis and dark matter production.
Search for B0 meson decays into Λ and missing energy with a hadronic tagging method at Belle
F. Tenchini;
2022-01-01
Abstract
We present a search for the decays of B0 mesons into a final state containing a Λ baryon and missing energy. These results are obtained from a 711fb−1 data sample that contains 772×10^6 BB¯ pairs and was collected near the Υ(4S) resonance with the Belle detector at the KEKB asymmetric-energy e+e− collider. We use events in which one B meson is fully reconstructed in a hadronic decay mode and require the remainder of the event to consist of only a single Λ. No evidence for these decays is found and we set 90% confidence level upper limits on the branching fractions in the range 2.1-3.8×10^−5. This measurement provides the world's most restrictive limits, with implications for baryogenesis and dark matter production.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
