Measurement of the Ratio of the B0 →d∗-τ+ντ and B0 →d∗-μ+νμ Branching Fractions Using Three-Prong τ -Lepton Decays

LHCb Collaboration

doi:10.1103/PhysRevLett.120.171802

Measurement of the Ratio of the B0 →d∗-τ+ντ and B0 →d∗-μ+νμ Branching Fractions Using Three-Prong τ -Lepton Decays

LHCb Collaboration

(Astro)-Particles Physics

Research output: Contribution to Journal › Article › Academic › peer-review

Abstract

The ratio of branching fractions R(D∗-)≡B(B0→D∗-τ+ντ)/B(B0→D∗-μ+νμ) is measured using a data sample of proton-proton collisions collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1. For the first time, R(D∗-) is determined using the τ-lepton decays with three charged pions in the final state. The B0→D∗-τ+ντ yield is normalized to that of the B0→D∗-π+π-π+ mode, providing a measurement of B(B0→D∗-τ+ντ)/B(B0→D∗-π+π-π+)=1.97±0.13±0.18, where the first uncertainty is statistical and the second systematic. The value of B(B0→D∗-τ+ντ)=(1.42±0.094±0.129±0.054)% is obtained, where the third uncertainty is due to the limited knowledge of the branching fraction of the normalization mode. Using the well-measured branching fraction of the B0→D∗-μ+νμ decay, a value of R(D∗-)=0.291±0.019±0.026±0.013 is established, where the third uncertainty is due to the limited knowledge of the branching fractions of the normalization and B0→D∗-μ+νμ modes. This measurement is in agreement with the standard model prediction and with previous results.

Original language	English
Article number	171802
Pages (from-to)	1-11
Number of pages	11
Journal	Physical Review Letters
Volume	120
Issue number	17
Early online date	25 Apr 2018
DOIs	https://doi.org/10.1103/PhysRevLett.120.171802
Publication status	Published - 2018

Funding

We express our gratitude to our colleagues in the CERN accelerator departments for the excellent performance of the LHC. We thank the technical and administrative staff at the LHCb institutes. We acknowledge support from CERN and from the national agencies: CAPES, CNPq, FAPERJ, and FINEP (Brazil); MOST and NSFC (China); CNRS/IN2P3 (France); BMBF, DFG, and MPG (Germany); INFN (Italy); NWO (Netherlands); MNiSW and NCN (Poland); MEN/IFA (Romania); MinES and FASO (Russia); MinECo (Spain); SNSF and SER (Switzerland); NASU (Ukraine); STFC (United Kingdom); NSF (USA). We acknowledge the computing resources that are provided by CERN, IN2P3 (France), KIT and DESY (Germany), INFN (Italy), SURF (Netherlands), PIC (Spain), GridPP (United Kingdom), RRCKI and Yandex LLC (Russia), CSCS (Switzerland), IFIN-HH (Romania), CBPF (Brazil), PL-GRID (Poland), and OSC (USA). We are indebted to the communities behind the multiple open-source software packages on which we depend. Individual groups or members have received support from AvH Foundation (Germany), EPLANET, Marie Skłodowska-Curie Actions, and ERC (European Union), ANR, Labex P2IO, ENIGMASS and OCEVU, and Région Auvergne-Rhóne-Alpes (France), RFBR and Yandex LLC (Russia), GVA, XuntaGal, and GENCAT (Spain), and Herchel Smith Fund, the Royal Society, the English-Speaking Union, and the Leverhulme Trust (United Kingdom).

Funders	Funder number
Agence Nationale de la Recherche
National Academy of Sciences of Ukraine
Federal Agency for Scientific Organizations
Narodowe Centrum Nauki
OCEVU
National Science Foundation
Institut national de physique nucléaire et de physique des particules
H2020 Marie Skłodowska-Curie Actions
Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro
Nederlandse Organisatie voor Wetenschappelijk Onderzoek
Ministry of Science and Technology, Taiwan
Herchel Smith Fund
Leverhulme Trust
Instituto Nazionale di Fisica Nucleare
Financiadora de Estudos e Projetos
Centre National de la Recherche Scientifique
Bundesministerium für Bildung und Forschung
Conselho Nacional de Desenvolvimento Científico e Tecnológico
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
Deutsche Forschungsgemeinschaft
European Commission
Région Auvergne-Rhône-Alpes
Russian Foundation for Basic Research
Yandex LLC
MinES
XuntaGal
Royal Society
Sociedad Española de Reumatología
European Research Council
EPLANET
Ministerstwo Nauki i Szkolnictwa Wyższego
Generalitat Valenciana
CERN
Alexander von Humboldt-Stiftung
National Natural Science Foundation of China
Science and Technology Facilities Council	ST/N000250/1, ST/H006737/1, LHCb Upgrades, GRIDPP, ST/J004332/1, 1681016, ST/K003410/1, 1796908, LHCb, ST/N000463/1, ST/N000455/1, ST/L003163/1, ST/N000242/1
Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung	166208

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

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10.1103/PhysRevLett.120.171802

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@article{7757bd600ee347c68e35383b3ff9f0a7,

title = "Measurement of the Ratio of the B0 →d∗-τ+ντ and B0 →d∗-μ+νμ Branching Fractions Using Three-Prong τ -Lepton Decays",

abstract = "The ratio of branching fractions R(D∗-)≡B(B0→D∗-τ+ντ)/B(B0→D∗-μ+νμ) is measured using a data sample of proton-proton collisions collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1. For the first time, R(D∗-) is determined using the τ-lepton decays with three charged pions in the final state. The B0→D∗-τ+ντ yield is normalized to that of the B0→D∗-π+π-π+ mode, providing a measurement of B(B0→D∗-τ+ντ)/B(B0→D∗-π+π-π+)=1.97±0.13±0.18, where the first uncertainty is statistical and the second systematic. The value of B(B0→D∗-τ+ντ)=(1.42±0.094±0.129±0.054)\% is obtained, where the third uncertainty is due to the limited knowledge of the branching fraction of the normalization mode. Using the well-measured branching fraction of the B0→D∗-μ+νμ decay, a value of R(D∗-)=0.291±0.019±0.026±0.013 is established, where the third uncertainty is due to the limited knowledge of the branching fractions of the normalization and B0→D∗-μ+νμ modes. This measurement is in agreement with the standard model prediction and with previous results.",

author = "R. Aaij and B. Adeva and M. Adinolfi and Z. Ajaltouni and S. Akar and J. Albrecht and F. Alessio and M. Alexander and \{Alfonso Albero\}, A. and S. Ali and G. Alkhazov and \{Alvarez Cartelle\}, P. and Alves, \{A. A.\} and S. Amato and S. Amerio and Y. Amhis and L. An and L. Anderlini and G. Andreassi and M. Andreotti and Andrews, \{J. E.\} and Appleby, \{R. B.\} and F. Archilli and P. D'Argent and \{Arnau Romeu\}, J. and A. Artamonov and M. Artuso and E. Aslanides and G. Auriemma and M. Baalouch and I. Babuschkin and S. Bachmann and \{Carvalho Akiba\}, K. and V. Coco and \{De Bruyn\}, K. and M. Ferro-Luzzi and T. Ketel and \{Van Leerdam\}, J. and T. Li and M. Merk and Onderwater, \{C. J.G.\} and G. Raven and M. Schiller and N. Serra and B. Storaci and V. Syropoulos and \{Van Tilburg\}, J. and S. Tolk and P. Tsopelas and N. Tuning and \{LHCb Collaboration\}",

year = "2018",

doi = "10.1103/PhysRevLett.120.171802",

language = "English",

volume = "120",

pages = "1--11",

journal = "Physical Review Letters",

issn = "0031-9007",

publisher = "American Physical Society",

number = "17",

}

TY - JOUR

T1 - Measurement of the Ratio of the B0 →d∗-τ+ντ and B0 →d∗-μ+νμ Branching Fractions Using Three-Prong τ -Lepton Decays

AU - Aaij, R.

AU - Adeva, B.

AU - Adinolfi, M.

AU - Ajaltouni, Z.

AU - Akar, S.

AU - Albrecht, J.

AU - Alessio, F.

AU - Alexander, M.

AU - Alfonso Albero, A.

AU - Ali, S.

AU - Alkhazov, G.

AU - Alvarez Cartelle, P.

AU - Alves, A. A.

AU - Amato, S.

AU - Amerio, S.

AU - Amhis, Y.

AU - An, L.

AU - Anderlini, L.

AU - Andreassi, G.

AU - Andreotti, M.

AU - Andrews, J. E.

AU - Appleby, R. B.

AU - Archilli, F.

AU - D'Argent, P.

AU - Arnau Romeu, J.

AU - Artamonov, A.

AU - Artuso, M.

AU - Aslanides, E.

AU - Auriemma, G.

AU - Baalouch, M.

AU - Babuschkin, I.

AU - Bachmann, S.

AU - Carvalho Akiba, K.

AU - Coco, V.

AU - De Bruyn, K.

AU - Ferro-Luzzi, M.

AU - Ketel, T.

AU - Van Leerdam, J.

AU - Li, T.

AU - Merk, M.

AU - Onderwater, C. J.G.

AU - Raven, G.

AU - Schiller, M.

AU - Serra, N.

AU - Storaci, B.

AU - Syropoulos, V.

AU - Van Tilburg, J.

AU - Tolk, S.

AU - Tsopelas, P.

AU - Tuning, N.

AU - LHCb Collaboration

PY - 2018

Y1 - 2018

N2 - The ratio of branching fractions R(D∗-)≡B(B0→D∗-τ+ντ)/B(B0→D∗-μ+νμ) is measured using a data sample of proton-proton collisions collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1. For the first time, R(D∗-) is determined using the τ-lepton decays with three charged pions in the final state. The B0→D∗-τ+ντ yield is normalized to that of the B0→D∗-π+π-π+ mode, providing a measurement of B(B0→D∗-τ+ντ)/B(B0→D∗-π+π-π+)=1.97±0.13±0.18, where the first uncertainty is statistical and the second systematic. The value of B(B0→D∗-τ+ντ)=(1.42±0.094±0.129±0.054)% is obtained, where the third uncertainty is due to the limited knowledge of the branching fraction of the normalization mode. Using the well-measured branching fraction of the B0→D∗-μ+νμ decay, a value of R(D∗-)=0.291±0.019±0.026±0.013 is established, where the third uncertainty is due to the limited knowledge of the branching fractions of the normalization and B0→D∗-μ+νμ modes. This measurement is in agreement with the standard model prediction and with previous results.

AB - The ratio of branching fractions R(D∗-)≡B(B0→D∗-τ+ντ)/B(B0→D∗-μ+νμ) is measured using a data sample of proton-proton collisions collected with the LHCb detector at center-of-mass energies of 7 and 8 TeV, corresponding to an integrated luminosity of 3 fb-1. For the first time, R(D∗-) is determined using the τ-lepton decays with three charged pions in the final state. The B0→D∗-τ+ντ yield is normalized to that of the B0→D∗-π+π-π+ mode, providing a measurement of B(B0→D∗-τ+ντ)/B(B0→D∗-π+π-π+)=1.97±0.13±0.18, where the first uncertainty is statistical and the second systematic. The value of B(B0→D∗-τ+ντ)=(1.42±0.094±0.129±0.054)% is obtained, where the third uncertainty is due to the limited knowledge of the branching fraction of the normalization mode. Using the well-measured branching fraction of the B0→D∗-μ+νμ decay, a value of R(D∗-)=0.291±0.019±0.026±0.013 is established, where the third uncertainty is due to the limited knowledge of the branching fractions of the normalization and B0→D∗-μ+νμ modes. This measurement is in agreement with the standard model prediction and with previous results.

UR - https://www.scopus.com/pages/publications/85046290953

UR - https://www.scopus.com/inward/citedby.url?scp=85046290953&partnerID=8YFLogxK

U2 - 10.1103/PhysRevLett.120.171802

DO - 10.1103/PhysRevLett.120.171802

M3 - Article

AN - SCOPUS:85046290953

SN - 0031-9007

VL - 120

SP - 1

EP - 11

JO - Physical Review Letters

JF - Physical Review Letters

IS - 17

M1 - 171802

ER -

Measurement of the Ratio of the B0 →d∗-τ+ντ and B0 →d∗-μ+νμ Branching Fractions Using Three-Prong τ -Lepton Decays

Abstract

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