New approaches to the direct search of BSM physics with Codex-b and LHCb experiments

This work presents studies in Beyond Standard Model Physics, using two different experiments, LHCb and future CODEX-b. Asearch for Dark Matter fromΛ decays is performed within theLHCbexperiment during the LHC Run II at a center of mass energy of √ = 13 TeV. Two dark matter operators are studied, ( ¯...

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Detalles Bibliográficos
Autor: López Soliño, Saúl
Tipo de recurso: tesis doctoral
Fecha de publicación:2024
País:España
Institución:Universidad de Santiago de Compostela (USC)
Repositorio:Minerva. Repositorio Institucional de la Universidad de Santiago de Compostela
Idioma:inglés
OAI Identifier:oai:minerva.usc.gal:10347/38874
Acceso en línea:https://hdl.handle.net/10347/38874
Access Level:acceso abierto
Palabra clave:Dark Matter
LHCb
Codex
221202 Partículas elementales
Descripción
Sumario:This work presents studies in Beyond Standard Model Physics, using two different experiments, LHCb and future CODEX-b. Asearch for Dark Matter fromΛ decays is performed within theLHCbexperiment during the LHC Run II at a center of mass energy of √ = 13 TeV. Two dark matter operators are studied, ( ¯ → DM) and ( ¯ → DM) with 0.940 GeV/c2 < (DM) < 4.430 GeV/c2, respectively. The Λ baryons originate in Σ(∗) decays. Λ → DM( → ) and Λ → DM( → ) are the final observed states. No signal is observed in any of the studied decay modes and the following upper limits are set for the first time: ℬ(( ¯ → DM)) < 8.96 × 10−5 − 6.23 × 10−4 for 0.940 GeV/c2 < (DM) < 3.0 GeV/c2 and ℬ(( ¯ → DM)) < 2.45 × 10−4 − 8.25 × 10−5 for 0.940 GeV/c2 < (DM) < 3.5 GeV/c2 at 95% CL. Within the CODEX-b, some studies for potential long lived particles searches are performed. A generator level efficiency for three different production modes (inclusive, Higgs-strahlung and weak-boson fusion) is computed in the framework of the CODEX-b experiment assuming a minimal Higgs portal model. These Higgs production modes are the dominant ones, while the Higgs portal decay models show a minimal decay model that would allow for future searches within the CODEX framework. This two experiments could also work together for collaborative searches, as showcased in this work.