{"id":{"repo_id":"qucosa-diss","oai_identifier":"oai:qucosa:de:qucosa:25095"},"canonical_url":"https://search.dev.ndltd.org/etd/qucosa-diss/oai:qucosa:de:qucosa:25095","repository":{"repo_id":"qucosa-diss","name":"QUCOSA","base_url":"http://www.qucosa.de/oai/"},"display":{"title":"Measurement of the Partial Branching Fraction for Inclusive Semileptonic B Meson Decays to Light Hadrons B->Xu l nu and an Improved Determination of the Quark-Mixing Matrix Element |V_ub|","abstract":"This thesis presents an analysis of inclusive semileptonic $B \\to X_u e \\nu$ decays using approximately 454 million $\\Upsilon(4S) \\to B \\bar{B}$ decays collected during the years 1999 to 2008 with the BABAR detector. The electron energy, $E_e$, and the invariant mass squared of the electron-neutrino pair,$ q^2$, are reconstructed, where the neutrino kinematics is deduced from the decay products of both B mesons. The final hadronic state,$ X_u$, consists of a sum of many hadronic channels, each of which contains at least one $u$ quark. The variables $q^2$ and $E_e$ are then combined to compute the maximum kinematically allowed invariant mass squared of the hadronic system, $s_h^{max}$. Using these kinematic quantities, the partial branching fraction, $\\Delta BR(B \\to X_u e \\nu)$, unfolded for detector effects, is measured to be $\\Delta BR(E_e>2.0 GeV, s_h^{max}<3.52 GeV^2) = (3.33 \\pm 0.18 \\pm 0.21) \\times 10^{-4} in the $\\Upsilon(4S)$ and \\Delta \\tilde{\\BR}(\\tilde E_e>1.9 GeV, \\tilde {s}^{max}_{h} < 3.5 GeV^2) = (4.57 \\pm 0.24 \\pm 0.32) \\times 10^{-4} in the $B$ meson rest frames. The quoted errors are statistical and systematic, respectively. The CKM matrix element $|V_{ub}|$ is determined from the measured $\\Delta \\tilde{\\BR}$ using theoretical calculation based on Heavy Quark Expansion. The result is $|V_{ub}| = (4.19 \\pm 0.18{}^{+0.26}_{-0.20} {}^{+0.26}_{-0.25}) \\times 10^{-3}, where the errors represent experimental uncertainties, uncertainties from HQE parameters and theoretical uncertainties, respectively.","abstract_html":"This thesis presents an analysis of inclusive semileptonic B \\to Xu e \\nu decays using approximately 454 million $\\Upsilon(4S) \\to B \\bar{B}$ decays collected during the years 1999 to 2008 with the BABAR detector. The electron energy, Ee, and the invariant mass squared of the electron-neutrino pair, q2, are reconstructed, where the neutrino kinematics is deduced from the decay products of both B mesons. The final hadronic state, Xu, consists of a sum of many hadronic channels, each of which contains at least one $u$ quark. The variables q2 and Ee are then combined to compute the maximum kinematically allowed invariant mass squared of the hadronic system, shmax. Using these kinematic quantities, the partial branching fraction, \\Delta BR(B \\to Xu e \\nu), unfolded for detector effects, is measured to be \\Delta BR(Ee>2.0 GeV, shmax<3.52 GeV2) = (3.33 \\pm 0.18 \\pm 0.21) \\times 10-4 in the \\Upsilon(4S) and \\Delta \\tilde{\\BR}(\\tilde Ee>1.9 GeV, \\tilde {s}maxh < 3.5 GeV2) = (4.57 \\pm 0.24 \\pm 0.32) \\times 10-4 in the B$ meson rest frames. The quoted errors are statistical and systematic, respectively. The CKM matrix element $|V_{ub}|$ is determined from the measured $\\Delta \\tilde{\\BR}$ using theoretical calculation based on Heavy Quark Expansion. The result is $|V_{ub}| = (4.19 \\pm 0.18{}^{+0.26}_{-0.20} {}^{+0.26}_{-0.25}) \\times 10^{-3}, where the errors represent experimental uncertainties, uncertainties from HQE parameters and theoretical uncertainties, respectively.","abstract_has_math":true,"creators":["Volk, Alexei"],"institution":"Technische Universität Dresden","degree_name":null,"degree_level":"thesis.doctoral","degree_discipline":null,"degree_department":null,"school":null,"contributors":["Kobel, Michael","Lacker, Heiko"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2009,"date_issued":"2009-06-22","date_published":"2009-06-22","updated_at":"2026-07-24T03:59:09Z","subjects":["CKM matrix element","semileptonic B decays","semileptonische B-Meson Zerfälle","CKM-Matrixelement"],"languages":[],"rights":[],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Kobel, Michael","Lacker, Heiko"]},{"key":"dc:creator","label":"Author","values":["Volk, Alexei"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:publisher","label":"Institution","values":["Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden","Technische Universität Dresden"]},{"key":"dc:type","label":"Dc Type","values":["doctoralThesis"]},{"key":"thesis:degree_level","label":"Degree Level","values":["thesis.doctoral"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["Technische Universität Dresden"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["CKM matrix element","semileptonic B decays","semileptonische B-Meson Zerfälle","CKM-Matrixelement"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["This thesis presents an analysis of inclusive semileptonic $B \\to X_u e \\nu$ decays using approximately 454 million $\\Upsilon(4S) \\to B \\bar{B}$ decays collected during the years 1999 to 2008 with the BABAR detector. The electron energy, $E_e$, and the invariant mass squared of the electron-neutrino pair,$ q^2$, are reconstructed, where the neutrino kinematics is deduced from the decay products of both B mesons. The final hadronic state,$ X_u$, consists of a sum of many hadronic channels, each of which contains at least one $u$ quark. The variables $q^2$ and $E_e$ are then combined to compute the maximum kinematically allowed invariant mass squared of the hadronic system, $s_h^{max}$. Using these kinematic quantities, the partial branching fraction, $\\Delta BR(B \\to X_u e \\nu)$, unfolded for detector effects, is measured to be $\\Delta BR(E_e>2.0 GeV, s_h^{max}<3.52 GeV^2) = (3.33 \\pm 0.18 \\pm 0.21) \\times 10^{-4} in the $\\Upsilon(4S)$ and \\Delta \\tilde{\\BR}(\\tilde E_e>1.9 GeV, \\tilde {s}^{max}_{h} < 3.5 GeV^2) = (4.57 \\pm 0.24 \\pm 0.32) \\times 10^{-4} in the $B$ meson rest frames. The quoted errors are statistical and systematic, respectively. The CKM matrix element $|V_{ub}|$ is determined from the measured $\\Delta \\tilde{\\BR}$ using theoretical calculation based on Heavy Quark Expansion. The result is $|V_{ub}| = (4.19 \\pm 0.18{}^{+0.26}_{-0.20} {}^{+0.26}_{-0.25}) \\times 10^{-3}, where the errors represent experimental uncertainties, uncertainties from HQE parameters and theoretical uncertainties, respectively."]},{"key":"dc:title","label":"Title","values":["Measurement of the Partial Branching Fraction for Inclusive Semileptonic B Meson Decays to Light Hadrons B->Xu l nu and an Improved Determination of the Quark-Mixing Matrix Element |V_ub|"]}]}],"canonical_facts":{"dc:contributor":["Kobel, Michael","Lacker, Heiko"],"dc:creator":["Volk, Alexei"],"dc:description.abstract":["This thesis presents an analysis of inclusive semileptonic $B \\to X_u e \\nu$ decays using approximately 454 million $\\Upsilon(4S) \\to B \\bar{B}$ decays collected during the years 1999 to 2008 with the BABAR detector. The electron energy, $E_e$, and the invariant mass squared of the electron-neutrino pair,$ q^2$, are reconstructed, where the neutrino kinematics is deduced from the decay products of both B mesons. The final hadronic state,$ X_u$, consists of a sum of many hadronic channels, each of which contains at least one $u$ quark. The variables $q^2$ and $E_e$ are then combined to compute the maximum kinematically allowed invariant mass squared of the hadronic system, $s_h^{max}$. Using these kinematic quantities, the partial branching fraction, $\\Delta BR(B \\to X_u e \\nu)$, unfolded for detector effects, is measured to be $\\Delta BR(E_e>2.0 GeV, s_h^{max}<3.52 GeV^2) = (3.33 \\pm 0.18 \\pm 0.21) \\times 10^{-4} in the $\\Upsilon(4S)$ and \\Delta \\tilde{\\BR}(\\tilde E_e>1.9 GeV, \\tilde {s}^{max}_{h} < 3.5 GeV^2) = (4.57 \\pm 0.24 \\pm 0.32) \\times 10^{-4} in the $B$ meson rest frames. The quoted errors are statistical and systematic, respectively. The CKM matrix element $|V_{ub}|$ is determined from the measured $\\Delta \\tilde{\\BR}$ using theoretical calculation based on Heavy Quark Expansion. The result is $|V_{ub}| = (4.19 \\pm 0.18{}^{+0.26}_{-0.20} {}^{+0.26}_{-0.25}) \\times 10^{-3}, where the errors represent experimental uncertainties, uncertainties from HQE parameters and theoretical uncertainties, respectively."],"dc:publisher":["Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden","Technische Universität Dresden"],"dc:subject":["CKM matrix element","semileptonic B decays","semileptonische B-Meson Zerfälle","CKM-Matrixelement"],"dc:title":["Measurement of the Partial Branching Fraction for Inclusive Semileptonic B Meson Decays to Light Hadrons B->Xu l nu and an Improved Determination of the Quark-Mixing Matrix Element |V_ub|"],"dc:type":["doctoralThesis"],"thesis:degree_level":["thesis.doctoral"],"thesis:institution_name":["Technische Universität Dresden"]},"updated_at":"2026-07-24T03:59:09Z"}