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Measurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 data

Time-dependent $CP$ asymmetries in the decay rates of the $D^0$ and $\overline{D}^0$ mesons into the $CP$-symmetric, singly Cabibbo-suppressed final states $K^+K^-$ and $\pi^+\pi^-$ are measured in $pp$ collisions collected by the LHCb experiment in 2015 and in 2016 at the centre-of-mass energy of $...

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Autor principal: Pajero, Tommaso
Lenguaje:eng
Publicado: 2018
Materias:
Acceso en línea:http://cds.cern.ch/record/2649367
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author Pajero, Tommaso
author_facet Pajero, Tommaso
author_sort Pajero, Tommaso
collection CERN
description Time-dependent $CP$ asymmetries in the decay rates of the $D^0$ and $\overline{D}^0$ mesons into the $CP$-symmetric, singly Cabibbo-suppressed final states $K^+K^-$ and $\pi^+\pi^-$ are measured in $pp$ collisions collected by the LHCb experiment in 2015 and in 2016 at the centre-of-mass energy of $13\,\text{TeV}$, corresponding to an integrated luminosity of $1.7\,\text{fb}^{-1}$. The strong-interaction decay $D^{*+} \rightarrow D^0 \pi^+$ is used to infer the flavour of the $D^0$ meson at production. The asymmetry between the effective decay widths of the $D^0$ and $\overline{D}^0$ decays, sensitive to indirect $CP$ violation, is measured to be \begin{align*} A_\Gamma(D^0\rightarrow K^+K^-) &= (-60.9 \pm 3.8 \pm 0.6 )\cdot 10^{-4},\\ A_\Gamma(D^0\rightarrow \pi^+\pi^-) &= (-62.5 \pm 6.7 \pm 0.5 )\cdot 10^{-4}, \end{align*} where the first uncertainty is statistical, the second one systematic and the central values are blinded pending the receipt of the approval of the analysis procedure by the LHCb collaboration. The obtained statistical precision is comparable to the previous, world-leading measurement of $A_\Gamma$ by the LHCb collaboration, whereas the systematic uncertainty is reduced by a factor of $\approx2$.
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spelling cern-26493672019-09-30T06:29:59Zhttp://cds.cern.ch/record/2649367engPajero, TommasoMeasurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 dataParticle Physics - ExperimentTime-dependent $CP$ asymmetries in the decay rates of the $D^0$ and $\overline{D}^0$ mesons into the $CP$-symmetric, singly Cabibbo-suppressed final states $K^+K^-$ and $\pi^+\pi^-$ are measured in $pp$ collisions collected by the LHCb experiment in 2015 and in 2016 at the centre-of-mass energy of $13\,\text{TeV}$, corresponding to an integrated luminosity of $1.7\,\text{fb}^{-1}$. The strong-interaction decay $D^{*+} \rightarrow D^0 \pi^+$ is used to infer the flavour of the $D^0$ meson at production. The asymmetry between the effective decay widths of the $D^0$ and $\overline{D}^0$ decays, sensitive to indirect $CP$ violation, is measured to be \begin{align*} A_\Gamma(D^0\rightarrow K^+K^-) &= (-60.9 \pm 3.8 \pm 0.6 )\cdot 10^{-4},\\ A_\Gamma(D^0\rightarrow \pi^+\pi^-) &= (-62.5 \pm 6.7 \pm 0.5 )\cdot 10^{-4}, \end{align*} where the first uncertainty is statistical, the second one systematic and the central values are blinded pending the receipt of the approval of the analysis procedure by the LHCb collaboration. The obtained statistical precision is comparable to the previous, world-leading measurement of $A_\Gamma$ by the LHCb collaboration, whereas the systematic uncertainty is reduced by a factor of $\approx2$.CERN-THESIS-2017-439oai:cds.cern.ch:26493672018-11-29T15:35:09Z
spellingShingle Particle Physics - Experiment
Pajero, Tommaso
Measurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 data
title Measurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 data
title_full Measurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 data
title_fullStr Measurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 data
title_full_unstemmed Measurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 data
title_short Measurement of the $CP$ violation parameter $A_\Gamma$ in $D^0\rightarrow K^+K^-$ and $D^0\rightarrow \pi^+\pi^-$ decays with LHCb Run 2 data
title_sort measurement of the $cp$ violation parameter $a_\gamma$ in $d^0\rightarrow k^+k^-$ and $d^0\rightarrow \pi^+\pi^-$ decays with lhcb run 2 data
topic Particle Physics - Experiment
url http://cds.cern.ch/record/2649367
work_keys_str_mv AT pajerotommaso measurementofthecpviolationparameteragammaind0rightarrowkkandd0rightarrowpipidecayswithlhcbrun2data