Evidence for B+ → τ+ντ decays and measurement of fB from Belle

Youngjoon Kwon

doi:10.1063/1.2714406

Evidence for B⁺ → τ⁺ν_τ decays and measurement of f_B from Belle

Youngjoon Kwon

Department of Physics

Research output: Chapter in Book/Report/Conference proceeding › Conference contribution

1 Citation (Scopus)

Abstract

We present the first evidence for B⁺ → τ ⁺ν_τ decay, using 414 fb^-1 of B meson decay event sample collected with the Belle detector at the KEKB e ⁺e^- collider. To cope with large missing energy due to multiple neutrinos in the final state, events are tagged by fully reconstructing one of the B mesons. We find the evidence for signal with a significance of 3.5 σ including systematic uncertainties. The branching fraction is measured to be B(B⁺→τ⁺ν_τ)=(1.79 _-0.49-0.51^+0.56+0.46)×10^-4. From this we obtain f_B=0.229_-0.031-0.037^+0.036+0.034GeV, the first direct determination of the B meson decay constant.

Original language	English
Title of host publication	QUARK CONFINEMENT AND THE HADRON SPECTRUM VII
Subtitle of host publication	7th Conference on Quark Confinement and the Hadron Spectrum, QCHS7
Pages	321-323
Number of pages	3
DOIs	https://doi.org/10.1063/1.2714406
Publication status	Published - 2007
Event	QUARK CONFINEMENT AND THE HADRON SPECTRUM VII: 7th Conference on Quark Confinement and the Hadron Spectrum, QCHS7 - Ponta Delgada, Acores, Portugal Duration: 2006 Sept 2 → 2006 Sept 7

Publication series

Name	AIP Conference Proceedings
Volume	892
ISSN (Print)	0094-243X
ISSN (Electronic)	1551-7616

Other

Other	QUARK CONFINEMENT AND THE HADRON SPECTRUM VII: 7th Conference on Quark Confinement and the Hadron Spectrum, QCHS7
Country/Territory	Portugal
City	Ponta Delgada, Acores
Period	06/9/2 → 06/9/7

All Science Journal Classification (ASJC) codes

Physics and Astronomy(all)

Access to Document

10.1063/1.2714406

Cite this

@inproceedings{6d287148477a4df9a8f21d583c1913ba,

title = "Evidence for B+ → τ+ντ decays and measurement of fB from Belle",

abstract = "We present the first evidence for B+ → τ +ντ decay, using 414 fb-1 of B meson decay event sample collected with the Belle detector at the KEKB e +e- collider. To cope with large missing energy due to multiple neutrinos in the final state, events are tagged by fully reconstructing one of the B mesons. We find the evidence for signal with a significance of 3.5 σ including systematic uncertainties. The branching fraction is measured to be B(B+→τ+ντ)=(1.79 -0.49-0.51+0.56+0.46)×10-4. From this we obtain fB=0.229-0.031-0.037+0.036+0.034GeV, the first direct determination of the B meson decay constant.",

author = "Youngjoon Kwon",

year = "2007",

doi = "10.1063/1.2714406",

language = "English",

isbn = "0735403961",

series = "AIP Conference Proceedings",

pages = "321--323",

booktitle = "QUARK CONFINEMENT AND THE HADRON SPECTRUM VII",

note = "QUARK CONFINEMENT AND THE HADRON SPECTRUM VII: 7th Conference on Quark Confinement and the Hadron Spectrum, QCHS7 ; Conference date: 02-09-2006 Through 07-09-2006",

}

Kwon, Y 2007, Evidence for B⁺ → τ⁺ν_τ decays and measurement of f_B from Belle. in QUARK CONFINEMENT AND THE HADRON SPECTRUM VII: 7th Conference on Quark Confinement and the Hadron Spectrum, QCHS7. AIP Conference Proceedings, vol. 892, pp. 321-323, QUARK CONFINEMENT AND THE HADRON SPECTRUM VII: 7th Conference on Quark Confinement and the Hadron Spectrum, QCHS7, Ponta Delgada, Acores, Portugal, 06/9/2. https://doi.org/10.1063/1.2714406

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AU - Kwon, Youngjoon

PY - 2007

Y1 - 2007

N2 - We present the first evidence for B+ → τ +ντ decay, using 414 fb-1 of B meson decay event sample collected with the Belle detector at the KEKB e +e- collider. To cope with large missing energy due to multiple neutrinos in the final state, events are tagged by fully reconstructing one of the B mesons. We find the evidence for signal with a significance of 3.5 σ including systematic uncertainties. The branching fraction is measured to be B(B+→τ+ντ)=(1.79 -0.49-0.51+0.56+0.46)×10-4. From this we obtain fB=0.229-0.031-0.037+0.036+0.034GeV, the first direct determination of the B meson decay constant.

AB - We present the first evidence for B+ → τ +ντ decay, using 414 fb-1 of B meson decay event sample collected with the Belle detector at the KEKB e +e- collider. To cope with large missing energy due to multiple neutrinos in the final state, events are tagged by fully reconstructing one of the B mesons. We find the evidence for signal with a significance of 3.5 σ including systematic uncertainties. The branching fraction is measured to be B(B+→τ+ντ)=(1.79 -0.49-0.51+0.56+0.46)×10-4. From this we obtain fB=0.229-0.031-0.037+0.036+0.034GeV, the first direct determination of the B meson decay constant.

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DO - 10.1063/1.2714406

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