Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]|
We report measurements of partial branching fractions for inclusive charmless semileptonic B decays B̅ →Xuℓν̅ and the determination of the Cabibbo–Kobayashi–Maskawa (CKM) matrix element |Vub|. The analysis is based on a sample of 467×10[superscript 6] Υ(4S)→BB̅ decays recorded with the BABAR detecto...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Physical Society
2012
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| Online Access: | http://hdl.handle.net/1721.1/74206 |
| _version_ | 1826191390347886592 |
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| author | Sciolla, Gabriella Dujmic, Denis Cowan, Ray F |
| author2 | Massachusetts Institute of Technology. Laboratory for Nuclear Science |
| author_facet | Massachusetts Institute of Technology. Laboratory for Nuclear Science Sciolla, Gabriella Dujmic, Denis Cowan, Ray F |
| author_sort | Sciolla, Gabriella |
| collection | MIT |
| description | We report measurements of partial branching fractions for inclusive charmless semileptonic B decays B̅ →Xuℓν̅ and the determination of the Cabibbo–Kobayashi–Maskawa (CKM) matrix element |Vub|. The analysis is based on a sample of 467×10[superscript 6] Υ(4S)→BB̅ decays recorded with the BABAR detector at the PEP-II e[superscript +]e[superscript -] storage rings. We select events in which the decay of one of the B mesons is fully reconstructed and an electron or a muon signals the semileptonic decay of the other B meson. We measure partial branching fractions ΔB in several restricted regions of phase space and determine the CKM element |V[subscript ub]| based on different QCD predictions. For decays with a charged lepton momentum p[subscript ℓ][superscript *]>1.0 GeV in the B meson rest frame, we obtain ΔB=(1.80±0.13[subscript stat]±0.15[subscript sys]±0.02[subscript theo])×10[superscript -3] from a fit to the two-dimensional M[subscript X]-q[superscript 2] distribution. Here, M[subscript X] refers to the invariant mass of the final state hadron X and q[superscript 2] is the invariant mass squared of the charged lepton and neutrino. From this measurement we extract |V[subscript ub]|=(4.33±0.24[subscript exp]±0.15[subscript theo])×10[superscript -3] as the arithmetic average of four results obtained from four different QCD predictions of the partial rate. We separately determine partial branching fractions for B̅[superscript 0] and B[superscript -] decays and derive a limit on the isospin breaking in B̅→X[subscript u]ℓν̅ decays. |
| first_indexed | 2024-09-23T08:55:08Z |
| format | Article |
| id | mit-1721.1/74206 |
| institution | Massachusetts Institute of Technology |
| language | en_US |
| last_indexed | 2024-09-23T08:55:08Z |
| publishDate | 2012 |
| publisher | American Physical Society |
| record_format | dspace |
| spelling | mit-1721.1/742062023-02-26T05:30:31Z Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]| Sciolla, Gabriella Dujmic, Denis Cowan, Ray F Massachusetts Institute of Technology. Laboratory for Nuclear Science Cowan, Ray Franklin Sciolla, Gabriella Dujmic, Denis We report measurements of partial branching fractions for inclusive charmless semileptonic B decays B̅ →Xuℓν̅ and the determination of the Cabibbo–Kobayashi–Maskawa (CKM) matrix element |Vub|. The analysis is based on a sample of 467×10[superscript 6] Υ(4S)→BB̅ decays recorded with the BABAR detector at the PEP-II e[superscript +]e[superscript -] storage rings. We select events in which the decay of one of the B mesons is fully reconstructed and an electron or a muon signals the semileptonic decay of the other B meson. We measure partial branching fractions ΔB in several restricted regions of phase space and determine the CKM element |V[subscript ub]| based on different QCD predictions. For decays with a charged lepton momentum p[subscript ℓ][superscript *]>1.0 GeV in the B meson rest frame, we obtain ΔB=(1.80±0.13[subscript stat]±0.15[subscript sys]±0.02[subscript theo])×10[superscript -3] from a fit to the two-dimensional M[subscript X]-q[superscript 2] distribution. Here, M[subscript X] refers to the invariant mass of the final state hadron X and q[superscript 2] is the invariant mass squared of the charged lepton and neutrino. From this measurement we extract |V[subscript ub]|=(4.33±0.24[subscript exp]±0.15[subscript theo])×10[superscript -3] as the arithmetic average of four results obtained from four different QCD predictions of the partial rate. We separately determine partial branching fractions for B̅[superscript 0] and B[superscript -] decays and derive a limit on the isospin breaking in B̅→X[subscript u]ℓν̅ decays. 2012-10-23T14:27:45Z 2012-10-23T14:27:45Z 2012-08 2011-12 Article http://purl.org/eprint/type/JournalArticle 1550-7998 1089-4918 http://hdl.handle.net/1721.1/74206 Lees, J. et al. “Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]|.” Physical Review D 86.3 (2012). © 2012 American Physical Society en_US http://dx.doi.org/10.1103/PhysRevD.86.032004 Physical Review D Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Physical Society APS |
| spellingShingle | Sciolla, Gabriella Dujmic, Denis Cowan, Ray F Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]| |
| title | Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]| |
| title_full | Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]| |
| title_fullStr | Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]| |
| title_full_unstemmed | Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]| |
| title_short | Study of B̅ →Xuℓν̅ decays in BB̅ events tagged by a fully reconstructed B-meson decay and determination of |V[subscript ub]| |
| title_sort | study of b xulν̅ decays in bb events tagged by a fully reconstructed b meson decay and determination of v subscript ub |
| url | http://hdl.handle.net/1721.1/74206 |
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