Observation of B-c(+) -> J/ psi D-s(+) and B-c(+) -> J/ psi D-s*(+) decays

The decays B-c(+) -> J/ psi D-s(+) and B-c(+) -> J/ psi D-s*(+) are observed for the first time using a dataset, corresponding to an integrated luminosity of 3 fb(-1), collected by the LHCb experiment in proton-proton collisions at center-of-mass energies of root s = 7 and 8 TeV. The statistical significance for both signals is in excess of 9 standard deviations. The following ratios of branching fractions are measured to be 'B(B-c(+) -> J/ psi D-s(+))/B(B-c(+) -> J/ psi pi(+)) = 2.90 +/- 0.57 +/- 0.24, B(B-c(+) -> J/psi D-s*(+))/B(B-c(+) -> J/ psi D-s(+)) = 2.37 +/- 0.56 +/- 0.10, where the first uncertainties are statistical and the second systematic. The mass of the B-c(+) meson is measured to be m(Bc+) = 6276.28 +/- 1.44(stat) +/- 0.36(syst) MeV/c(2), using the B-c(+) -> J/ psi D-s(+) decay mode.

À propos de ce résultat

Cette page est générée automatiquement et peut contenir des informations qui ne sont pas correctes, complètes, à jour ou pertinentes par rapport à votre recherche. Il en va de même pour toutes les autres pages de ce site. Veillez à vérifier les informations auprès des sources officielles de l'EPFL.

Concepts associés

Chargement

Publications associées

Chargement

Résumé

Official source

https://infoscience.epfl.ch/record/188938?ln=fr

À propos de ce résultat

Concepts associés (12)

Concepts associés

Chargement

Publications associées (110)

Chargement

Afficher plus

Publications associées

Chargement

Luminosité

En astronomie, la luminosité est la quantité totale d'énergie émise par unité de temps (le flux énergétique), par une étoile, une galaxie, ou n'importe quel autre objet céleste. Elle s'exprime en pr

LHCb

LHCb (Large Hadron Collider beauty experiment : Expérience du LHC sur le quark beauté) est une expérience de physique des particules utilisant les collisions de protons produites au collisionneur LHC

Luminosité solaire

vignette|Evolution de la luminosité solaire au cours du temps. En astrophysique, la luminosité solaire, égale à celle du Soleil et notée L, est l'unité de luminosité conventionnellement utilisée pou

First Observation of a Baryonic B-c(+) Decay

Liupan An, Aurelio Bay, Marc-Olivier Bettler, Frédéric Blanc, Joël Bressieux, Peter Clarke, Victor Coco, Greig Alan Cowan, Adam Davis, Michel De Cian, Hans Dijkstra, Mirco Dorigo, Frédéric Guillaume Dupertuis, Paolo Durante, Christoph Frei, Sebastiana Gianì, Guido Haefeli, Xiaoxue Han, Pierre Jaton, Chitsanu Khurewathanakul, Ilya Komarov, Yiming Li, Pietro Marino, Maurizio Martinelli, Bastien Luca Muster, Tatsuya Nakada, Matthew Needham, Niko Neufeld, Luca Pescatore, Cédric Potterat, Jessica Prisciandaro, Barinjaka Rakotomiaramanana, Gerhard Raven, Julien Rouvinet, Olivier Schneider, Liang Sun, Frédéric Teubert, Mark Tobin, Minh Tâm Tran, Maria Vieites Diaz, Jian Wang, Jean Wicht, Songmei Wu, Zhirui Xu, Lei Zhang, Yi Zhang

A baryonic decay of the B-c(+) meson, B-c(+) -> J/psi p (p) over bar pi(+) is observed for the first time, with a significance of 7.3 standard deviations, in pp collision data collected with the LHCb detector and corresponding to an integrated luminosity of 3.0 fb(-1) taken at center-of-mass energies of 7 and 8 TeV. With the B-c(+) -> J/psi pi(+) decay as the normalization channel, the ratio of branching fractions is measured to be B(B-c(+) -> J/psi p (p) over bar pi(+)) /B(B-c(+) -> J/psi pi(+)) = 0.143(-0.034)(+0.039) (stat) +/- 0.013 (syst). The mass of the B-c(+) messon is determined as M(B-c(+)) = 6274.0 +/- 0.4 (sysst) MeV/c(2), using the B-c(+) -> J/psi p (p) over bar pi(+) channel.

Amer Physical Soc2014

Chargement

Measurement of CP Violation in B-0 -> D+D- Decays

Liupan An, Guido Andreassi, Aurelio Bay, Violaine Bellée, Federico Betti, Marc-Olivier Bettler, Frédéric Blanc, Maxim Borisyak, Peter Clarke, Victor Coco, Greig Alan Cowan, Adam Davis, Michel De Cian, Hans Dijkstra, Mirco Dorigo, Paolo Durante, François Fleuret, Christoph Frei, Sebastiana Gianì, Olivier Göran Girard, Elena Graverini, Guido Haefeli, Xiaoxue Han, Thibaud Humair, Chitsanu Khurewathanakul, Ilya Komarov, Axel Kuonen, Yiming Li, Pietro Marino, Maurizio Martinelli, Tatsuya Nakada, Matthew Needham, Niko Neufeld, Preema Rennee Pais, Luca Pescatore, Anton Petrov, Cédric Potterat, Jessica Prisciandaro, Renato Quagliani, Gerhard Raven, Federico Leo Redi, Olivier Schneider, Maxime Schubiger, Pavol Stefko, Liang Sun, Frédéric Teubert, Mark Tobin, Minh Tâm Tran, Maria Vieites Diaz, Jian Wang, Jean Wicht, Zhirui Xu, Hang Yin, Lei Zhang, Yi Zhang, Yu Zheng

The CP violation observables S and C in the decay channel B-0 -> D+D- are determined from a sample of proton-proton collisions at center-of-mass energies of 7 and 8 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 3 fb(-1). The observable S describes CP violation in the interference between mixing and the decay amplitude, and C parametrizes direct CP violation in the decay. The following values are obtained from a flavor-tagged, decay-time-dependent analysis: S = -0.54(-0.16)(+0.17) (stat) +/- 0.05(syst) ,C=0.26(-0.17)(+0.18) (stat) +/- 0.02(syst). These values provide evidence for CP violation at a significance level of 4.0 standard deviations. The phase shift due to higher-order standard model corrections is constrained to a small value of Delta phi = -0.16(-0.21)(+0.19) rad.

Amer Physical Soc2016

Chargement

Observation of B-c(+) -> (DK+)-K-0 Decays

Liupan An, Guido Andreassi, Vladislav Balagura, Aurelio Bay, Violaine Bellée, Federico Betti, Marc-Olivier Bettler, Frédéric Blanc, Maxim Borisyak, Peter Clarke, Victor Coco, Greig Alan Cowan, Adam Davis, Michel De Cian, Hans Dijkstra, Mirco Dorigo, Paolo Durante, François Fleuret, Christoph Frei, Sebastiana Gianì, Olivier Göran Girard, Elena Graverini, Guido Haefeli, Xiaoxue Han, Thibaud Humair, Chitsanu Khurewathanakul, Ilya Komarov, Axel Kuonen, Yiming Li, Pietro Marino, Maurizio Martinelli, Katharina Müller, Tatsuya Nakada, Matthew Needham, Niko Neufeld, Preema Rennee Pais, Luca Pescatore, Anton Petrov, Cédric Potterat, Jessica Prisciandaro, Renato Quagliani, Gerhard Raven, Federico Leo Redi, Olivier Schneider, Maxime Schubiger, Pavol Stefko, Liang Sun, Frédéric Teubert, Mark Tobin, Minh Tâm Tran, Jian Wang, Jean Wicht, Zhirui Xu, Hang Yin, Yi Zhang, Lei Zhang, Yu Zheng

Using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb(-1), recorded by the LHCb detector at center-of-mass energies of 7 and 8 TeV, the B-c(+) -> (DK+)-K-0 decay is observed with a statistical significance of 5.1 standard deviations. By normalizing to B-c(+) -> (D) over bar (0)pi(+) decays, a measurement of the branching fraction multiplied by the production rates for B-c(+) relative to B+ mesons in the LHCb acceptance is obtained, R-D0K = (f(c)/f(u)) x B(B-c(+) -> (DK+)-K-0) = (9.3(-2.5)(+2.8) +/- 0.6) x 10(-7), where the first uncertainty is statistical and the second is systematic. This decay is expected to proceed predominantly through weak annihilation and penguin amplitudes, and is the first B-c(+) decay of this nature to be observed.

2017

Chargement

Afficher plus