Measurement of the ratio of partial branching fractions of inclusive B-* Xulν to B-* Xclν and the ratio of their spectra with hadronic tagging

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10510922" target="_blank" >RIV/00216208:11320/25:10510922 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=rtXS29m_-9" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=rtXS29m_-9</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1103/PhysRevD.111.092016" target="_blank" >10.1103/PhysRevD.111.092016</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Measurement of the ratio of partial branching fractions of inclusive B-* Xulν to B-* Xclν and the ratio of their spectra with hadronic tagging

Popis výsledku v původním jazyce

We present a measurement of the ratio of partial branching fractions of the semileptonic inclusive decays, B-* Xul nu to B-* Xcl nu, where l 1/4 (e; mu), using the full Belle sample of 772 x 106 BB pairs collected at the Y(4S) resonance. The identification of inclusive B-* Xul nu decays is difficult due to the abundance of Cabibbo-Kobayashi-Maskawa-favored B-* Xcl nu events, which share a similar event topology. To minimize dependence on the modeling of these channels, a data-driven description of B-* Xcl nu is employed. The ratio is measured via a two-dimensional fit to the squared four-momentum transfer to the lepton pair, and the charged lepton energy in the B meson rest frame, where the latter must be larger than 1 GeV, covering approximately 86% and 78% of the B-* Xul nu and B-* Xcl nu phase space, respectively. We find oB(B-* Xul nu)/oB(B-* Xcl nu) 1/4 (1.99 +/- 0.17stat +/- 0.16syst) x 10-2, where the uncertainties are statistical and systematic, respectively. We extract jVubj/jVcbj using two theoretical calculations for the partial decay rate of B-* Xul nu, finding (jVubj/jVcbj)BLNP 1/4 (9.81 +/- 0.42stat +/- 0.38syst +/- 0.51or(B-*Xul nu) +/- 0.20or(B-*Xcl nu)) x 10-2 and (jVubj/jVcbj)GGOU 1/4 (10.06 +/- 0.43stat +/- 0.39syst +/- 0.23or(B-*Xul nu) +/- 0.20or(B-*Xcl nu)) x 10-2, where the third and fourth uncertainties are from the partial decay rates of B-* Xul nu and B-* Xcl nu, respectively. In addition, we report the partial branching fractions separately for charged and neutral B meson decays, and for electron and muon decay channels. We place a limit on isospin breaking in B-* Xul nu decays, and find no indication of lepton flavor universality violation in either the charmed or charmless mode. Furthermore, we unfold the B-* Xul nu and B-* Xcl nu yields and report the differential ratio in lepton energy and four-momentum transfer squared.

Název v anglickém jazyce

Measurement of the ratio of partial branching fractions of inclusive B-* Xulν to B-* Xclν and the ratio of their spectra with hadronic tagging

Popis výsledku anglicky

We present a measurement of the ratio of partial branching fractions of the semileptonic inclusive decays, B-* Xul nu to B-* Xcl nu, where l 1/4 (e; mu), using the full Belle sample of 772 x 106 BB pairs collected at the Y(4S) resonance. The identification of inclusive B-* Xul nu decays is difficult due to the abundance of Cabibbo-Kobayashi-Maskawa-favored B-* Xcl nu events, which share a similar event topology. To minimize dependence on the modeling of these channels, a data-driven description of B-* Xcl nu is employed. The ratio is measured via a two-dimensional fit to the squared four-momentum transfer to the lepton pair, and the charged lepton energy in the B meson rest frame, where the latter must be larger than 1 GeV, covering approximately 86% and 78% of the B-* Xul nu and B-* Xcl nu phase space, respectively. We find oB(B-* Xul nu)/oB(B-* Xcl nu) 1/4 (1.99 +/- 0.17stat +/- 0.16syst) x 10-2, where the uncertainties are statistical and systematic, respectively. We extract jVubj/jVcbj using two theoretical calculations for the partial decay rate of B-* Xul nu, finding (jVubj/jVcbj)BLNP 1/4 (9.81 +/- 0.42stat +/- 0.38syst +/- 0.51or(B-*Xul nu) +/- 0.20or(B-*Xcl nu)) x 10-2 and (jVubj/jVcbj)GGOU 1/4 (10.06 +/- 0.43stat +/- 0.39syst +/- 0.23or(B-*Xul nu) +/- 0.20or(B-*Xcl nu)) x 10-2, where the third and fourth uncertainties are from the partial decay rates of B-* Xul nu and B-* Xcl nu, respectively. In addition, we report the partial branching fractions separately for charged and neutral B meson decays, and for electron and muon decay channels. We place a limit on isospin breaking in B-* Xul nu decays, and find no indication of lepton flavor universality violation in either the charmed or charmless mode. Furthermore, we unfold the B-* Xul nu and B-* Xcl nu yields and report the differential ratio in lepton energy and four-momentum transfer squared.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10300 - Physical sciences

Projekt

Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2025

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Physical Review D

ISSN

2470-0010

e-ISSN

2470-0029

Svazek periodika

111

Číslo periodika v rámci svazku

09

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

23

Strana od-do

092016

Kód UT WoS článku

001512777000001

EID výsledku v databázi Scopus

2-s2.0-105007631515