Inclusive search for Long-lived light neutralino in B decays with baryonic R-parity violation at Belle II

Sumitted to PubDB: 2026-08-22

Category: Master Thesis

Principal Authors	Tasmay Goswami
Date	2026-04-22
Belle II Number	BELLE2-MTHESIS-2026-062
Abstract	We investigate the prospects of searching for a light, long-lived neutralino in a baryon number-violating R-parity violating supersymmetric framework at the Belle II experiment. In this scenario, a GeV-scale bino-like neutralino is produced in B-meson decays and subsequently decays into hadronic final states with a macroscopic lifetime, leading to displaced vertex signatures inside the detector. An inclusive search strategy is adopted, targeting multi-track displaced vertices without requiring full reconstruction of specific decay modes. This approach enhances sensitivity by capturing a broad class of signal topologies while it definitely requires strong background suppression. The analysis is carried out within the Belle II analysis software framework, focusing on the suppression of Standard Model backgrounds using displaced track parameter variables and vertex-level observables. Building on existing phenomenological study, which indicate that Belle II can probe neutralino masses in the range of 2.7-4.3 GeV under the assumption of supressed background, this work aims to develop and optimize selection strategies to achieve such background suppression in a realistic experimental setting.
Institute	IISc