Publications associées à Positon

Characterization of Transverse Instabilities Driven by Electron Cloud

Electron cloud continues to be one of the main limiting factors of the Large Hadron Collider (LHC), the biggest accelerator at CERN. These clouds form in the beam chamber when positively charged particles are passing through and cause unwanted effects in b ...

EPFL2024

Collimation simulations for the FCC-ee

Tatiana Pieloni, Giovanni Iadarola, Milica Rakic, Bruce Roderik, Guillaume Clément Broggi, Félix Simon Carlier

The collimation system of the Future Circular Collider, operating with leptons (FCC-ee), must protect not only the experiments against backgrounds, but also the machine itself from beam losses. With a 17.8 MJ stored energy of the electron and positron beam ...

Iop Publishing Ltd2024

Two-particle azimuthal correlations in γp interactions using pPb collisions at √sNN=8.16 TeV

Matthias Finger, Konstantin Androsov, Qian Wang, Jan Steggemann, Yiming Li, Varun Sharma, Xin Chen, Arvind Shah, Rakesh Chawla, Jian Wang, João Miguel das Neves Duarte, Tagir Aushev, Matthias Wolf, Yi Zhang, Tian Cheng, Yixing Chen, Werner Lustermann, Andromachi Tsirou, Alexis Kalogeropoulos, Andrea Rizzi, Ioannis Papadopoulos, Paolo Ronchese, Hua Zhang, Leonardo Cristella, Siyuan Wang, Jessica Prisciandaro, Peter Hansen, Tao Huang, David Vannerom, Michele Bianco, Sebastiana Gianì, Davide Di Croce, Kun Shi, Wei Shi, Abhisek Datta, Wei Sun, Jian Zhao, Thomas Berger, Federica Legger, Bandeep Singh, Ji Hyun Kim, Donghyun Kim, , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

First self-consistent simulations of trapped electron clouds in a gyrotron gun and comparison with experiments

Stefano Alberti, Jean-Philippe Hogge, Ioannis Pagonakis, Joaquim Loizu Cisquella, Jérémy Genoud, Francesco Romano

We report on the initial validation of the novel code FENNECS, which simulates the spontaneous formation of trapped electron clouds in coaxial geometries with strong externally applied azimuthal flows and in the presence of a residual neutral gas. For this ...

American Institute of Physics (AIP)2023

Modelling of nonneutral plasmas trapped by electric and magnetic fields relevant to gyrotron electron guns

Guillaume Michel Le Bars

Gyrotrons are a class of high-power vacuum-electronics microwave sources, which are envisioned to play an important role in the domain of magnetically confined fusion plasmas. Indeed, only gyrotrons are capable of producing continuous electromagnetic waves ...

EPFL2023

Towards a muon collider

Riccardo Rattazzi, Varun Sharma, Siyu Chen, Xavier Buffat, Brian Quinn Henning, Filippo Nardi, Niko Neufeld, Luca Bottura, Andrea Wulzer, Roberto Franceschini, Alfredo Glioti, Riccardo Torre, Lorenzo Ricci, Marco Valente, Xiaoran Zhao, Xin Sun, Alexej Grudiev, Ennio Salvioni, Marco Calviani, Jian Tang, Jing Shu, Tao Han, Alessandro Valenti, Laura Buonincontri, Luca Giambastiani

A muon collider would enable the big jump ahead in energy reach that is needed for a fruitful exploration of fundamental interactions. The challenges of producing muon collisions at high luminosity and 10 TeV centre of mass energy are being investigated by ...

Springer2023

Search for supersymmetry in final states with a single electron or muon using angular correlations and heavy-object identification in proton-proton collisions at √s=13 TeV

Matthias Finger, Konstantin Androsov, Qian Wang, Jan Steggemann, Anna Mascellani, Yiming Li, Varun Sharma, Xin Chen, Rakesh Chawla, Matteo Galli, Jian Wang, João Miguel das Neves Duarte, Tagir Aushev, Matthias Wolf, Yi Zhang, Lei Zhang, Tian Cheng, Yixing Chen, Werner Lustermann, Andromachi Tsirou, Alexis Kalogeropoulos, Andrea Rizzi, Ioannis Papadopoulos, Paolo Ronchese, Hua Zhang, Leonardo Cristella, Siyuan Wang, Tao Huang, David Vannerom, Michele Bianco, Sebastiana Gianì, Sun Hee Kim, Davide Di Croce, Kun Shi, Wei Shi, Abhisek Datta, Jian Zhao, Federica Legger, Gabriele Grosso, Ji Hyun Kim, Donghyun Kim, , , , , , , , , , , , , , , , , , , , , , , , , , , , , ,

Integrated electronics for time-of-flight positron emission tomography photodetectors

Andrada Alexandra Muntean

Positron emission tomography is a nuclear imaging technique well known for its use in oncology for cancer diagnosis and staging. A PET scanner is a complex machine which comprises photodetectors placed in a ring configuration that detect gamma photons gen ...

EPFL2023

DARKFLUX: A new tool to analyze indirect-detection spectra of next-generation dark matter models

Emma Elizabeth Tolley

We present DARKFLUX, a software tool designed to analyze indirect-detection signatures for next-generation models of dark matter (DM) with multiple annihilation channels. Version 1.0 of this tool accepts user-generated models with 2 -> 2 tree-level dark ma ...

ELSEVIER2022

Probing multi-particle unitarity with the Landau equations

Miguel Alexandre Ribeiro Correia, Alexander Zhiboedov, Amit Sever

We consider the 2 -> 2 scattering amplitude of identical massive particles. We identify the Landau curves in the multi-particle region 16m(2)

2022

High-Performance CMOS SPAD-Based Sensors for Time-of-Flight PET Applications

Francesco Gramuglia

Detecting light, photon by photon, has been possible since the 1930s, with the invention of the photomultiplier tube (PMT). However, it is only since the 1970s, that solid-state single-photon detectors have emerged and only since 2003 that a new technology ...

EPFL2022

Search for relativistic fractionally charged particles in space

Jennifer Maria Frieden, Chiara Perrina, Jian Wang, Zhirui Xu, Yi Zhang, Siyuan Wang, Songmei Wu, Junqiu Liu, Johan Juul Chang, Jie Chen, Cheng Zhao, Wei Li, Yong Yang, Yi Wang, Hao Liu, Xiao Wang, Shuai Liu, Wenyu Zhang, Xuan Li, Yao Zhang, Ming Gao, Arshia Ruina, Andrii Kotenko

More than a century after the performance of the oil drop experiment, the possible existence of fractionally charged particles (FCPs) still remains unsettled. The search for FCPs is crucial for some extensions of the Standard Model in particle physics. Mos ...

American Physical Society2022

Low-scale leptogenesis with flavour and CP symmetries

Marco Drewes, Juraj Klaric, Yannis Georis

We consider a type-I seesaw framework endowed with a flavour symmetry, belonging to the series of non-abelian groups increment (3 n(2)) and increment (6 n(2)), and a CP symmetry. Breaking these symmetries in a non-trivial way results in the right-handed ne ...

Springer Nature2022

Uniting Low-Scale Leptogenesis Mechanisms

Mikhail Chapochnikov, Inar Timiryasov, Juraj Klaric

In this Letter we demonstrate that what was previously considered as different mechanisms of baryon asymmetry generation involving two right-handed Majorana neutrinos with masses far below the Grand Unified Theory scale-leptogenesis via neutrino oscillatio ...

AMER PHYSICAL SOC2021

Self-interacting neutrinos: Solution to Hubble tension versus experimental constraints

Emmanuel Stamou

Exotic self-interactions among the Standard Model neutrinos have been proposed as a potential reason behind the tension in the expansion rate, H-0, of the universe inferred from different observations. We constrain this proposal using electroweak precision ...

American Physical Society2021

Post-irradiation examination of refractory metal candidates for antiproton targets at the European Laboratory for Particle Physics (CERN)

Elvis Fornasiere

The AD-target (Antiproton Decelerator Target) is the main antiparticle production element of the CERNâ s (European Organization for Nuclear Research) AD (Antiproton Decelerator) complex. Antiprotons are produced by colliding a pulsed 1.5 * 10^13 ppp (prot ...

EPFL2020

First observation of spalling in tantalum at high temperatures induced by high energy proton beam impacts

Philippe Spätig, Elvis Fornasiere, Marco Calviani

Spalling in tantalum has been observed in an experiment aiming at testing an antiproton production target prototype at CERN’s HiRadMat Facility. The experiment consisted in impacting 47 intense and high-energy proton beams onto a target equipped with ten c ...

2020

Spontaneous baryogenesis from axions with generic couplings

Valerie Fiona Domcke

Axion-like particles can source the baryon asymmetry of our Universe through spontaneous baryogenesis. Here we clarify that this is a generic outcome for essentially any coupling of an axion-like particle to the Standard Model, requiring only a non-zero ve ...

Springer Nature2020

Investigation of the fine structure of antihydrogen

Shirit Cohen

At the historic Shelter Island Conference on the Foundations of Quantum Mechanics in 1947, Willis Lamb reported an unexpected feature in the fine structure of atomic hydrogen: a separation of the 2S(1/2) and 2P(1/2) states(1). The observation of this separ ...

2020

Search for flavoured leptonic decays of long-lived particles in the LHCb detector

Matthieu Philippe Luther Marinangeli

New massive long-lived particles (LLP) are predicted by multiple beyond the Standard Model theories. This thesis presents the search of such long-lived particles decaying leptonically in the

e \mu \nu

final state. The search is performed using 2.31 fb$^{ ...

EPFL2020