Dortmund 2021 – scientific programme

Parts | Days | Selection | Search | Updates | Downloads | Help

T: Fachverband Teilchenphysik

T 56: Flavour physics III

T 56.6: Talk

Wednesday, March 17, 2021, 17:15–17:30, Tf

Measurement of inclusive B→ X_u ℓ ν decay with hadronic tagging at Belle — Forian Bernlochner, •Lu Cao, William Sutcliffe, and Raynette van Tonder for the Belle collaboration — Physikalisches Institut, Universität Bonn, Germany

Precise measurement of the CKM matrix element |V_ub| permits a stringent test of the Standard Model (SM) of particle physics through its role of constraining the apex of the unitarity triangle. The sizeable tension between the exclusive and inclusive determinations of |V_ub| is limiting the precision of this test, which evoked many investigations in the past decades. With the full data set of the Belle experiment comprising 772 million BB pairs, we measure partial branching fractions in three phase-space regions covering about 31% to 86% of the accessible B→ X_u ℓ ν phase-space. The |V_ub| value is extracted based on a two-dimensional fit of the hadronic mass spectrum and the four-momentum transfer squared distribution in the phase-space of E_ℓ^B>1 GeV. In addition, the unfolded differential distributions of the key kinematic variables will be provided for the first time, which are crucial for future model-independent determinations of |V_ub|.