Publications related to Flavor-changing neutral current

Testing lepton flavour universality in $B^+\to K^+\pi^+\pi^-\ell^+\ell^-$ decays with LHCb

This PhD thesis aims at testing one of the fundamental properties of the Standard Model (SM) of particle physics: the lepton flavour universality (LFU), which states that

W

and

Z

bosons are equally coupled to the three lepton generations. In this work, ...

EPFL2023

Measurement of the B+ -> rho0 mu+ nu differential branching fraction

Veronica Sølund Kirsebom

The tension between different determinations of the CKM matrix element Vub using measurements of either exclusive or inclusive semileptonic decays represents a long-standing puzzle in flavour physics. To resolve this, measurements of new exclusive channels ...

EPFL2023

Search for Higgs boson and observation of Z boson through their decay into a charm quark-antiquark pair in boosted topologies in proton-proton collisions at √s=13 TeV

Jian Wang, Matthias Finger, Qian Wang, Yiming Li, João Miguel das Neves Duarte, Matthias Wolf, Varun Sharma, Yi Zhang, Lei Zhang, Tian Cheng, Yixing Chen, Alexis Kalogeropoulos, Ioannis Papadopoulos, Hua Zhang, Siyuan Wang, Xin Chen, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Davide Di Croce, Jian Zhao, Rakesh Chawla, Jan Steggemann, Konstantin Androsov, Anna Mascellani, Federica Legger, Matteo Galli, Gabriele Grosso

A search for the standard model (SM) Higgs boson (H) produced with transverse momentum (p(T)) greater than 450 GeV and decaying to a charm quark-antiquark (c (c) over bar) pair is presented. The search is performed using proton-proton collision data collec ...

Amer Physical Soc2023

Test of Lepton Universality in b→sℓ+ℓ− Decays

The first simultaneous test of muon-electron universality using

B^{+}\rightarrow K^{+}\ell^{+}\ell^{-}

and

B^{0}\rightarrow K^{*0}\ell^{+}\ell^{-}

decays is performed, in two ranges of the dilepton invariant-mass squared,

q^{2}

. The analysis uses bea ...

2023

An allowed window for heavy neutral leptons below the kaon mass

Alexey Boyarsky, Oleg Ruchayskiy, Inar Timiryasov, Juraj Klaric, Kyrylo Bondarenko

The extension of the Standard Model with two gauge-singlet Majorana fermions can simultaneously explain two beyond-the-Standard-model phenomena: neutrino masses and oscillations, as well as the origin of the matter-antimatter asymmetry in the Universe. The ...

Springer Nature2021

On lepton number violation in heavy neutrino decays at colliders

Marco Drewes, Juraj Klaric

We study the perspective to observe lepton number violating signatures from heavy Majorana neutrino decays at colliders in view of the requirement to explain the light neutrino masses via the seesaw mechanism. In the minimal model with only two heavy neutr ...

Springer Nature2019

Search for B- -> mu(-)(nu)over-bar(mu) Decays at the Belle Experiment

Mingkui Wang, Olivier Schneider, Chao Wang, Sun Hee Kim, Tara Nanut, Jun Yong Kim, Chang-Hyun Park, Seyed Sina Mirrazavi Salehian, Joo Yeon Kim, Timothy Chi Hin Liew, Yong Chan Choi, Martin Lubej, Wondwossen Wubie Eshetu, Johannes Julius Thomas Marinus Swartjes, Takayuki Yamashita

We report the results of a search for the rare, purely leptonic decay B- -> mu(-)(nu) over bar (mu) performed with a 711 fb(-1) data sample that contains 772 x 10(6) B (B) over bar pairs, collected near the Upsilon(4S) resonance with the Belle detector at ...

2018

The bearable compositeness of leptons

Luca Vecchi

Partial compositeness as a theory of flavor in the lepton sector is assessed. We begin presenting the first systematic analysis of neutrino mass generation in this context, and identifying the distinctive mass textures. We then update the bounds from charg ...

Springer Nature2018

Study of charmonium production in b-hadron decays and first evidence for the decay B-s(0) -> phi phi phi

Jian Wang, Olivier Schneider, Zhirui Xu, Yiming Li, Yi Zhang, Lei Zhang, Aurelio Bay, Guido Haefeli, Jessica Prisciandaro, Tatsuya Nakada, Christoph Frei, Mark Tobin, Frédéric Blanc, Minh Tâm Tran, Greig Alan Cowan, Maurizio Martinelli, Vladislav Balagura, Donal Patrick Hill, Liang Sun, Pietro Marino, Luca Pescatore, François Fleuret, Mirco Dorigo, Jean Wicht, Sebastiana Gianì, Liupan An, Elena Graverini, Federico Leo Redi, Chitsanu Khurewathanakul, Ilya Komarov, Plamen Hristov Hopchev, Renato Quagliani, Maxime Schubiger, Hang Yin, Guido Andreassi, Violaine Bellée, Olivier Göran Girard, Axel Kuonen, Preema Rennee Pais, Aravindhan Venkateswaran, Pavol Stefko, Maria Elena Stramaglia, Katharina Müller

Using decays to f-meson pairs, the inclusive production of charmonium states in b-hadron decays is studied with pp collision data corresponding to an integrated luminosity of 3.0 fb(-1), collected by the LHCb experiment at centre-of-mass energies of 7 and ...

Springer Nature2017

Constraints on violation of Lorentz invariance from atmospheric showers initiated by multi-TeV photons

Sergey Sibiryakov

Parameterizing hypothetical violation of Lorentz invariance at high energies using the framework of effective quantum field theory, we discuss its effect on the formation of atmospheric showers by very-high-energy gamma rays. In the scenario where Lorentz ...

Iop Publishing Ltd2017

Measurement of the CKM angle gamma using B (0) -> DK (*0) with D -> K-S(0) pi (+) pi (-) decays

Jian Wang, Olivier Schneider, Zhirui Xu, Yiming Li, Yi Zhang, Lei Zhang, Aurelio Bay, Guido Haefeli, Jessica Prisciandaro, Tatsuya Nakada, Christoph Frei, Mark Tobin, Frédéric Blanc, Minh Tâm Tran, Michel De Cian, Greig Alan Cowan, Maurizio Martinelli, Donal Patrick Hill, Liang Sun, Pietro Marino, Luca Pescatore, François Fleuret, Mirco Dorigo, Jean Wicht, Liupan An, Elena Graverini, Federico Leo Redi, Chitsanu Khurewathanakul, Ilya Komarov, Renato Quagliani, Maxime Schubiger, Hang Yin, Guido Andreassi, Bastien Luca Muster, Violaine Bellée, Maria Vieites Diaz, Olivier Göran Girard, Axel Kuonen, Albert Puig Navarro, Alessandro Mapelli, Katharina Müller, Lucía Castillo García

A model-dependent amplitude analysis of the decay B (0) -> D(K (S) (0) pi (+) pi (-))K (au 0) is performed using proton-proton collision data corresponding to an integrated luminosity of 3.0 fb(-1), recorded at and 8 TeV by the LHCb experiment. The CP viol ...

Springer Nature2016

Observation of the Lambda(0)(b) -> Lambda phi decay

Jian Wang, Olivier Schneider, Zhirui Xu, Yiming Li, Yi Zhang, Lei Zhang, Aurelio Bay, Guido Haefeli, Jessica Prisciandaro, Tatsuya Nakada, Christoph Frei, Mark Tobin, Frédéric Blanc, Minh Tâm Tran, Michel De Cian, Greig Alan Cowan, Maurizio Martinelli, Donal Patrick Hill, Liang Sun, Pietro Marino, Luca Pescatore, François Fleuret, Mirco Dorigo, Jean Wicht, Sebastiana Gianì, Liupan An, Elena Graverini, Federico Leo Redi, Chitsanu Khurewathanakul, Ilya Komarov, Renato Quagliani, Maxime Schubiger, Hang Yin, Guido Andreassi, Bastien Luca Muster, Violaine Bellée, Maria Vieites Diaz, Olivier Göran Girard, Axel Kuonen, Alessandro Mapelli

The Lambda(0)(b) -> Lambda phi decay is observed using data corresponding to an integrated luminosity of 3.0 fb(-1) recorded by the LHCb experiment. The decay proceeds at leading order via a b -> ss loop transition and is therefore sens ...

Elsevier Science Bv2016

b-flavour tagging in pp collisions at LHCb

Measurements of CP violation and flavour oscillations of neutral B mesons require the knowledge of the meson flavour at the production time. Flavour-tagging algorithms in the LHCb experiment allow to perform such measurements with very high precision. Rece ...

Soc Italiana Fisica2016

Measurement of CP violation in B-s(0) ->Phi Phi decays

Jian Wang, Olivier Schneider, Zhirui Xu, Yiming Li, Yi Zhang, Lei Zhang, Aurelio Bay, Guido Haefeli, Jessica Prisciandaro, Tatsuya Nakada, Christoph Frei, Mark Tobin, Frédéric Blanc, Minh Tâm Tran, Michel De Cian, Greig Alan Cowan, Maurizio Martinelli, Vladislav Balagura, Donal Patrick Hill, Liang Sun, Pietro Marino, Luca Pescatore, Mirco Dorigo, Jean Wicht, Liupan An, Chitsanu Khurewathanakul, Ilya Komarov, Bastien Luca Muster, Maria Vieites Diaz, Frédéric Guillaume Dupertuis, Julien Rouvinet, Pierre Jaton, Barinjaka Rakotomiaramanana, Joël Bressieux, Songmei Wu

A measurement of the decay time-dependent CP-violating asymmetry in B-s(0) -> phi phi decays is presented, along with measurements of the T-odd triple-product asymmetries. In this decay channel, the CP-violating weak phase arises from the interference betw ...

American Physical Society2014

Latest LHCb results

Maurizio Martinelli

The LHCb experiment is one of the major research projects at the Large Hadron Collider. Its acceptance and instrumentation is optimised to perform highprecision studies of flavour physics and particle production in a unique kinematic range at unprecedented ...

EDP Sciences2014