Publications by Guillaume Max Pietrzyk

Study of B-c(+) decays to charmonia and three light hadrons

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Renato Quagliani, Veronica Sølund Kirsebom

Using proton-proton collision data, corresponding to an integrated luminosity of 9 fb(-1) collected with the LHCb detector, seven decay modes of the B-C(+) meson into a J/psi or psi(2S) meson and three charged hadrons, kaons or pions, are studied. The deca ...

Springer Nature2022

Measurement of the photon polarization in Lambda(0)(b) -> Lambda gamma decays

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Renato Quagliani, Veronica Sølund Kirsebom

The photon polarization in b -> s gamma transitions is measured for the first time in radiative b -baryon decays exploiting the unique spin structure of Lambda(0)(b)-> Lambda(gamma) decays. A data sample corresponding to an integrated luminosity of 6 fb(-1 ...

American Physical Society2022

Searches for rare B-s(0) and B-0 decays into four muons

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Renato Quagliani, Veronica Sølund Kirsebom

Searches for rare B-s(0) and B-0 decays into four muons are performed using proton-proton collision data recorded by the LHCb experiment, corresponding to an integrated luminosity of 9 fb(-1). Direct decays and decays via light scalar and J/psi resonances ...

Springer Nature2022

Search for the radiative Xi(-)(b) -> Xi(-)gamma decay

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Veronica Sølund Kirsebom, Ettore Zaffaroni

The first search for the rare radiative decay Xi(-)(b) -> Xi(-)gamma is performed using data collected by the LHCb experiment in proton-proton collisions at a center-of-mass energy of 13TeV, corresponding to an integrated luminosity of 5.4 fb(-1). The Xi(- ...

Springer Nature2022

J/ψ photoproduction in Pb-Pb peripheral collisions at √sNN=5 TeV

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Veronica Sølund Kirsebom, Ettore Zaffaroni

The photoproduction of J/ψ mesons at low transverse momentum is studied in peripheral lead-lead collisions collected by the LHCb Collaboration at a center-of-mass energy per nucleon pair of 5TeV, corresponding to an integrated luminosity of 210 μb−1. The J ...

2022

Study of Z Bosons Produced in Association with Charm in the Forward Region

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Renato Quagliani, Veronica Sølund Kirsebom

Events containing a Z boson and a charm jet are studied for the first time in the forward region of proton-proton collisions. The data sample used corresponds to an integrated luminosity of 6 fb(-1) collected at a center-of-mass energy of 13 TeV with the L ...

AMER PHYSICAL SOC2022

Analysis of Neutral B-Meson Decays into Two Muons

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Veronica Sølund Kirsebom, Ettore Zaffaroni

Branching fraction and effective lifetime measurements of the rare decay B0s→μ+μ− and searches for the decays B0→μ+μ− and B0s→μ+μ−γ are reported using proton-proton collision data collected with the LHCb detector at center-of-mass energies of 7, 8, and 13 ...

2022

Observation of Two New Excited Ξ 0 b States Decaying to Λ 0 b K − π +

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Renato Quagliani, Veronica Sølund Kirsebom

Two narrow resonant states are observed in the ??0bK??????? mass spectrum using a data sample of protonproton collisions at a center-of-mass energy of 13 TeV, collected by the LHCb experiment and corresponding to an integrated luminosity of 6 fb???1. The m ...

2022

Precision measurement of neutral charm meson mixing parameters

Guillaume Max Pietrzyk

This thesis presents a measurement of the neutral charm meson mixing parameters

y_{C\!P}^{KK} - y_{C\!P}^{K\pi}

and

y_{C\!P}^{\pi\pi} - y_{C\!P}^{K\pi}

using

D^0 \rightarrow K^-K^+

,

D^0 \rightarrow \pi^-\pi^+

and

D^0 \rightarrow K^-\pi^+

decays. ...

EPFL2022

Observation of Lambda b(0) -> D(+)p pi(-)pi(-) and Lambda b(0) -> D-*+p pi(-)pi(-) decays

Lesya Shchutska, Olivier Schneider, Aurelio Bay, Guido Haefeli, Frédéric Blanc, Tatsuya Nakada, Michel De Cian, Elena Graverini, Renato Quagliani, Veronica Sølund Kirsebom

The multihadron decays Lambda(0)(b) -> D(+)p pi(-)pi(-) and Lambda(0 )(b)-> D-*+p pi(-)pi(-) are observed in data corresponding to an integrated luminosity of 3fb(-1), collected in proton-proton collisions at centre-of-mass energies of 7 and 8 TeV by the L ...

Springer Nature2022