Christoph Frei

Publications associées (560)

À propos
Confidentialité
Mentions légales

Graph Chatbot

Measurement of the electron reconstruction efficiency at LHCb

Olivier Schneider, Yiming Li, Guido Haefeli, Frédéric Blanc, Aurelio Bay, Tatsuya Nakada, Michel De Cian, Christoph Frei, Luca Pescatore, Elena Graverini

The single electron track-reconstruction efficiency is calibrated using a sample corresponding to 1.3 fb(-1) of pp collision data recorded with the LHCb detector in 2017. This measurement exploits B+ -> J/psi (e(+)e(-))K+ decays, where one of the electrons ...

2019

Measurement of the CP-violating phase phi(s) from B-s(0) -> J/psi pi(+)pi(-) decays in 13 TeV pp collisions

Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Frédéric Blanc, Christoph Frei, Tatsuya Nakada, Mingkui Wang, Mercedes Hannelore Rittmann-Frank, Michael Thompson McCann

Decays of B-s(0) and (B) over bar (0)(s) mesons into J/psi pi(+)pi(-) final states are studied in a data sample corresponding to 1.9 fb(-1) of integrated luminosity collected with the LHCb detector in 13 TeV pp collisions. A time-dependent amplitude analys ...

2019

Observation of New Resonances in the Lambda(0)(b)pi(+)pi(-) System

Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Frédéric Blanc, Christoph Frei, Tatsuya Nakada, Michel De Cian, Luca Pescatore, Chitsanu Khurewathanakul

We report the observation of a new structure in the Lambda(0)(b)pi(+)pi(- )spectrum using the full LHCb data set of pp collisions, corresponding to an integrated luminosity of 9 fb(-1), collected at root s = 7, 8, and 13 TeV. A study of the structure sugge ...

2019

Amplitude analysis of the B0 (s)! K0K0 decays and measurement of the branching fraction of the B0! K0K0 decay

Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Frédéric Blanc, Christoph Frei, Tatsuya Nakada, Michel De Cian, Luca Pescatore, Chitsanu Khurewathanakul

The B0 K0K0 and B0 s K0K0 decays are studied using proton-proton collision data corresponding to an integrated luminosity of 3 fb. An untagged and timeintegrated amplitude analysis of B0 (s) (K+)(K) decays in two-body invariant mass regions of 150MeV/c2 ar ...

Springer Nature2019

Search for the doubly charmed baryon Xi(+)(cc)

Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Frédéric Blanc, Christoph Frei, Tatsuya Nakada, Michel De Cian, Luca Pescatore, Chitsanu Khurewathanakul

A search for the doubly charmed baryon.+ cc is performed through its decay to the.+ c K- p+ final state, using proton-proton collision data collected with the LHCb detector at centre-of-mass energies of 7, 8 and 13 TeV. The data correspond to a total integ ...

SCIENCE PRESS2019

Measurement of CP violation in the B-s(0)-> phi phi decay and search for the B-0 -> phi phi decay

Olivier Schneider, Yiming Li, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Christoph Frei, Tatsuya Nakada, Michel De Cian, Luca Pescatore, Chitsanu Khurewathanakul

A measurement of the time-dependent CP-violating asymmetry in Bs0 ->phi phi = 7 TeV in 2011, 8 TeV in 2012 and 13 TeV in 2015 and 2016, a signal yield of around 9000 Bs0 ->phi phi decays is obtained. The CP-violating phase phi sss over bar is measured to b ...

Springer Nature2019

Model-Independent Observation of Exotic Contributions to B degrees -> J/psi K+pi(-) Decays

Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Luca Pescatore

An angular analysis of B degrees -> J/psi K+pi(-) decays is performed, using proton-proton collision data corresponding to an integrated luminosity of 3 fb(-1) collected with the LHCb detector. The m(K+pi(-) ) spectrum is divided into fine bins. In each m( ...

2019

Observation of an Excited B-c(+) State

Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Luca Pescatore, Elena Graverini

Using pp collision data corresponding to an integrated luminosity of 8.5 fb(-1) recorded by the LHCb experiment at center-of-mass energies of root s = 7, 8, and 13 TeV, the observation of an excited B-c(+) state in the B-c(+)pi(+)pi(-) invariant-mass spect ...

2019

Observation of a Narrow Pentaquark State, P-c(4312)(+), and of the Two-Peak Structure of the P-c(4450)(+)

Olivier Schneider, Aurelio Bay, Yiming Li, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Matthieu Philippe Luther Marinangeli

A narrow pentaquark state, P-c(4312)(+), decaying to J/psi p, is discovered with a statistical significance of 7.3 sigma in a data sample of Lambda(0)(b) -> J/psi pK(-) decays, which is an order of magnitude larger than that previously analyzed by the LHCb ...

2019

Prompt Lambda(+)(c) baryons and D-0 meson production cross-section and nuclear modification in pPb collisions at root S-NN=5.02 TeV with the LHCb detector

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Luca Pescatore, François Fleuret

A(c)(+) baryons and D-0 mesons are studied in pPb collisions at root S-NN = 5.02 TeV. The nuclear modification factor and forward-backward cross-section asymmetry are measured in order to study the cold nuclear matter effects. The prompt A(c)(+) production ...

2019

Page 8 sur 56

Prompt Lambda(+)(c) baryons and D-0 meson production cross-section and nuclear modification in pPb collisions at root S-NN=5.02 TeV with the LHCb detector

Olivier Schneider, Aurelio Bay, Guido Haefeli, Christoph Frei, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Luca Pescatore, François Fleuret

2019