A new algorithm for identifying the flavour of B0s mesons at LHCb
A new algorithm for the determination of the initial flavour of $B_s^0$ mesons is presented. The algorithm is based on two neural networks and exploits the $b$ hadron production mechanism at a hadron collider. The first network is trained to select charged kaons produced in association with the $B_s...
| Main Authors: | , , , , , , , , , , , , , |
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| 格式: | Journal article |
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Institute of Physics
2016
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| _version_ | 1826281438021943296 |
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| author | Cheung, S Evans, T Gandini, P Hadavizadeh, T Harnew, N Hill, D Jalocha, P John, M Lupton, O Malde, S Nandi, A Topp-Jorgenson, S Wilkinson, G The LHCb Collaboration |
| author_facet | Cheung, S Evans, T Gandini, P Hadavizadeh, T Harnew, N Hill, D Jalocha, P John, M Lupton, O Malde, S Nandi, A Topp-Jorgenson, S Wilkinson, G The LHCb Collaboration |
| author_sort | Cheung, S |
| collection | OXFORD |
| description | A new algorithm for the determination of the initial flavour of $B_s^0$ mesons is presented. The algorithm is based on two neural networks and exploits the $b$ hadron production mechanism at a hadron collider. The first network is trained to select charged kaons produced in association with the $B_s^0$ meson. The second network combines the kaon charges to assign the $B_s^0$ flavour and estimates the probability of a wrong assignment. The algorithm is calibrated using data corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by the LHCb experiment in proton-proton collisions at 7 and 8 TeV centre-of-mass energies. The calibration is performed in two ways: by resolving the $B_s^0$-$\bar{B}_s^0$ flavour oscillations in $B_s^0 \to D_s^- \pi^+$ decays, and by analysing flavour-specific $B_{s 2}^{*}(5840)^0 \to B^+ K^-$ decays. The tagging power measured in $B_s^0 \to D_s^- \pi^+$ decays is found to be $(1.80 \pm 0.19({\rm stat}) \pm 0.18({\rm syst}))$\%, which is an improvement of about 50\% compared to a similar algorithm previously used in the LHCb experiment. |
| first_indexed | 2024-03-07T00:28:48Z |
| format | Journal article |
| id | oxford-uuid:7f0f4b9c-7e3d-4ec6-a7c3-e3595db31e7f |
| institution | University of Oxford |
| last_indexed | 2024-03-07T00:28:48Z |
| publishDate | 2016 |
| publisher | Institute of Physics |
| record_format | dspace |
| spelling | oxford-uuid:7f0f4b9c-7e3d-4ec6-a7c3-e3595db31e7f2022-03-26T21:14:24ZA new algorithm for identifying the flavour of B0s mesons at LHCbJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:7f0f4b9c-7e3d-4ec6-a7c3-e3595db31e7fSymplectic Elements at OxfordInstitute of Physics2016Cheung, SEvans, TGandini, PHadavizadeh, THarnew, NHill, DJalocha, PJohn, MLupton, OMalde, SNandi, ATopp-Jorgenson, SWilkinson, GThe LHCb CollaborationA new algorithm for the determination of the initial flavour of $B_s^0$ mesons is presented. The algorithm is based on two neural networks and exploits the $b$ hadron production mechanism at a hadron collider. The first network is trained to select charged kaons produced in association with the $B_s^0$ meson. The second network combines the kaon charges to assign the $B_s^0$ flavour and estimates the probability of a wrong assignment. The algorithm is calibrated using data corresponding to an integrated luminosity of 3 fb$^{-1}$ collected by the LHCb experiment in proton-proton collisions at 7 and 8 TeV centre-of-mass energies. The calibration is performed in two ways: by resolving the $B_s^0$-$\bar{B}_s^0$ flavour oscillations in $B_s^0 \to D_s^- \pi^+$ decays, and by analysing flavour-specific $B_{s 2}^{*}(5840)^0 \to B^+ K^-$ decays. The tagging power measured in $B_s^0 \to D_s^- \pi^+$ decays is found to be $(1.80 \pm 0.19({\rm stat}) \pm 0.18({\rm syst}))$\%, which is an improvement of about 50\% compared to a similar algorithm previously used in the LHCb experiment. |
| spellingShingle | Cheung, S Evans, T Gandini, P Hadavizadeh, T Harnew, N Hill, D Jalocha, P John, M Lupton, O Malde, S Nandi, A Topp-Jorgenson, S Wilkinson, G The LHCb Collaboration A new algorithm for identifying the flavour of B0s mesons at LHCb |
| title | A new algorithm for identifying the flavour of B0s mesons at LHCb |
| title_full | A new algorithm for identifying the flavour of B0s mesons at LHCb |
| title_fullStr | A new algorithm for identifying the flavour of B0s mesons at LHCb |
| title_full_unstemmed | A new algorithm for identifying the flavour of B0s mesons at LHCb |
| title_short | A new algorithm for identifying the flavour of B0s mesons at LHCb |
| title_sort | new algorithm for identifying the flavour of b0s mesons at lhcb |
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