Journées de Rencontre des Jeunes Chercheurs 2019

24 nov. 2019, 18:30 → 30 nov. 2019, 08:50 Europe/Paris

Centre Moulin Mer

 

(English version, for French see below)

Organised by the sections "Fields and Particles" and "Nuclear Physics" of the Société Française de Physique (SFP), the "Journées de Rencontre des Jeunes Chercheurs 2019" welcomes all PhD students (from the first to the last year) and young postdocs.

This year it will be held from the 24th to 30th November 2019 at the Centre Moulin Mer in Finistère.

The JRJCs are an occasion for each participant to present their work in a convivial atmosphere and to obtain from their colleagues an overview of the current research going on in France in the domain.

This year the following subjects are proposed : - Nuclear Energy - Nuclear Structure and Dynamics - Nuclear Astrophysics - Medical Physics - Hadronic physics - Heavy Ion Collisions - Cosmology - Instrumentation - Standard Model (electroweak) - Beyond the Standard Model - Theoretical Physics - Neutrinos - Astroparticles - Heavy Flavour

The working language of the JRJC is French, but for the non-francophones talks can be given in English. The social program includes, other than an excursion, one or two evening talks which would be open to the general public. For any other information please feel free to contact the secretary or any member of the organising committee (see below). The deadline for registration is the 25th October 2019.

 

 

(français)

Organisées par les divisions "Champs et Particules" et "Physique Nucléaire" de la Société Française de Physique (SFP), les Journées de Rencontre des Jeunes Chercheurs 2019 s'adressent à tous les étudiants en thèse (de la première à la dernière année) et aux jeunes post-doctorants.

Elles auront lieu du 24 au 30 novembre 2019 et se tiendront au centre Moulin Mer en Finistère.

Les JRJC sont l'occasion pour chaque participant de présenter ses travaux de recherche dans une ambiance conviviale et de partager avec ses collègues une vue d'ensemble des différentes recherches menées à l'heure actuelle dans sa spécialité et dans des domaines proches.

Les thèmes proposés cette année sont les suivants : - Énergie nucléaire - Structure et dynamique nucléaire - Astrophysique nucléaire - Physique médicale - Physique hadronique - Collisions d'ions lourds - Cosmologie - Instrumentation - Modèle standard électrofaible - Au-delà du modèle standard - Physique théorique - Neutrinos - Astroparticules - Saveurs lourdes

La langue de travail des JRJC est le français, mais les non-francophones peuvent donner leur exposé en anglais. Le programme social comprend, outre une excursion dans la région, une ou deux conférences en soirée pouvant être ouvertes au public. Le date limite d'inscription c'est le 25 octobre 2019. Pour tout renseignement complémentaire, n'hésitez pas à contacter notre secrétariat ou bien un membre du comité d'organisation:

 

 

- Pauline Ascher (CENBG)                             ascher@cenbg.in2p3.fr
- Aoife Bharucha (CPT)                                  Aoife.Bharucha@cpt.univ-mrs.fr 
- Francois Brun (CEA Saclay)                         francois.brun@cea.fr 
- Nicolas Chanon (IPNL)                                 nicolas.pierre.chanon@cern.ch
- Emmanuel Chauveau (CENBG)                    chauveau@cenbg.in2p3.fr 
- Isabelle Cossin (LPNHE)                               cossin@lpnhe.in2p3.fr
- Rachel Delorme (IMNC)                                delorme@imnc.in2p3.fr 
- Romain Gaior (LPNHE)                                 romain.gaior@lpnhe.in2p3.fr
- Julien Masbou (SUBATECH)                        masbou@subatech.in2p3.fr 
- Laure Massacrier (IPNO)                               massacrier@ipno.in2p3.fr 
- Antonio Uras (IPNL)                                     antonio.uras@cern.ch
- Dimitris Varouchas (LAL)                             Dimitris.Varouchas@cern.ch

 

                        

 

                                                   

 

 

affiche_JRJC2019.jpg

Circulaire2019_2_FR.pdf

Circular2019_2_EN.pdf

dimanche 24 novembre

18:30 → 19:30 Inscriptions / pot d'acceuil

19:30 → 21:30 Diner

lundi 25 novembre

09:00 → 10:30 Instrumentation: Session I

Président de session: Sabrina Sacerdoti (LAL)

09:00 Introduction

Orateur: Sabrina Sacerdoti (APC-Paris,France)

instrumentationJRJC.pdf

09:30 Beam optics design for PRAE linac and FCC-ee injector positron linac

Orateur: Bowen BAI (Laboratoire de l'accélérateur linéaire (LAL))

JRJC19_B.Bai.pdf

10:00 Impedance Simulations And Measurements For ThomX

Orateur: Ezgi Ergenlik (Laboratoire de l'accélérateur linéaire (LAL))

jrjc_ezgiergenlik.pptx

10:30 → 11:00 Coffee Break

11:00 → 12:30 Instrumentation: Session II

Président de session: Sabrina Sacerdoti (LAL)

11:00 Amelioration du calorimetre à Argon liquide d'ATLAS (phase I et II)

Orateur: Etienne FORTIN (Aix Marseille Univ, CNRS/IN2P3, CPPM, Marseille, France)

06-11-19-ATLAS-JJC.pdf

11:30 Performance of pixel n-in-p planar sensors for ITk to operate in High-Luminosity LHC

Orateur: Reem Taibah (LPNHE)

Performance of pixel n-in-p planar sensors for ITk to operate in High-Luminosity LHC

12:00 Parametric Instabilities study of the ground-based interferometer gravitational waves detector Virgo

Now that the global LIGO-Virgo network has successfully detected gravitational waves from compact binary coalescences, a key challenge is to improve the detector sensitivity in order to detect more transient sources — weaker or located further away. The detectors' sensitivity can be enhanced by increasing the laser power travelling within the arm cavities, for it reduces the effect of the laser quantum phase noise, which is the fundamental noise that dominates the sensitivity in the high-frequency range (above a few hundreds of Hz). However, a nonlinear optomechanical phenomenon that has long been studied, and which is called parametric instabilities (PI), may limit the amount of energy stored in the Fabry-Perot resonator, and thus the laser power.

PI comes from the coupling of three modes: a mirror mechanical mode (MM) that sets the mirror surface in motion, the fundamental optical mode of an optical cavity (TEM00), and a higher order optical mode (HOM). Photons scattering from the TEM00 to a HOM can generate an optical beat note if the difference in frequencies of the two optical modes is equal to the MM resonance frequency. This beat note, in turn, can either damp or increase the mechanical motion via radiation pressure. The latter effect could lead to an excitation, that is to say, first exponentially growing, and then reaches a plateau after some time. The signal associated with this mirror excitation would be aliasing in the detection band, thus saturating the electronics.

In 2015, during the Observing Run 1 (O1), LIGO observed PIs when a mirror mechanical mode at 15 kHz became unstable, for an intracavity power of 50 kW. That is why we are investigating possible PIs in Virgo. In our simulations, we vary several parameters to include measurement uncertainties and possible deviations between the nominal configuration of the detector and the actual one. Current results show that, with an intracavity power of 160 kW (nominal value for the Observation Run 3, currently ongoing) and all mechanical mode quality factors equal to 10^7, one could get up to a few tens of unstable modes, depending on the mirror radii of curvature. Lower quality factors (in agreement with measurements in situ) should allow Virgo not to face any PI for the time being -- and indeed none has been observed so far.

Orateur: David Cohen

191125 - JRJC 2019.pdf

191125 - JRJC 2019.pptx

12:30 → 14:00 Lunch

14:00 → 14:30 Instrumentation: Session III

Président de session: Sabrina Sacerdoti (LAL)

14:00 2D fast timing readout system and hits clustering approach for new generation of RPC

Orateur: Konstantin Shchablo

Shchablo_JRJC.pdf

14:30 → 15:30 Flavour physics

Président de session: Joao Coelho (LAL)

14:30 Introduction to Flavour Physics

Orateur: Joao Coelho (LAL)

20191125_JRJC_FlavourPhysics_JCoelho.pdf

15:00 Testing lepton flavor universality with the B0 -> K* tau+ tau- decay at LHCb

Lepton flavor universality is a property of the Standard Model (SM) of particle physics according to which the coupling constants of the three families of leptons to the weak bosons are the same. The difference between the leptons is consequently due only to their masses. Even though this property has been experimentally tested, recently some tensions between SM predictions and measured values have arisen, pointing in the direction of a violation of lepton flavor universality. Modes with $\tau$ leptons in the final state are experimentally challenging and still largely unexplored, with lots of room left for possible new physics effects. In particular the $B^0 \rightarrow K^* \tau^+ \tau^-$ decay is expected to be suppressed in the SM, with a predicted branching ratio of $10^{−7}$, but which could be enhanced by up to factors of $10^3$ in new models, especially those involving the existence of leptoquarks.

Orateur: Jacopo Cerasoli (Aix Marseille Univ, CNRS/IN2P3, CPPM, Marseille, France)

JRJC_Jacopo_25112019.pdf

15:30 → 16:00 Coffee break

16:00 → 18:00 Theoretical Physics: Session I

Président de session: ANDREAS GOUDELIS (LPC - Clermont Ferrand)

16:00 Introduction

Orateur: Andreas Goudelis (LPC - Clermont Ferrand)

AndreasJRJC2019.pdf

16:30 Hadronic vacuum polarization contribution to the muon magnetic anomaly from lattice QCD

Anomalous magnetic moments have guided the evolution of quantum field theory ever since its earliest stages, serving both as a stringent test of the theory at increasingly higher levels of precision and as a possible window to new physics. After decades of perfect agreement, the measured muon magnetic moment (which is known to a precision of about 0.5 parts per million both from theory and experiment) now deviates from the theoretical expectation by around 3.5σ. In order to accentuate or resolve this discrepancy, an experiment at Fermilab is currently underway and is aiming to improve the precision of the measurement to 0.14 ppm. But the theoretical calculation has to be improved as well. The largest source of error are low energy hadronic contributions, that can be evaluated either via a phenomenological approach or ab initio, directly from the standard model Lagrangian, using lattice QCD. In this talk we will see how lattice QCD can be used to compute the leading hadronic contribution to the muon magnetic moment: the one induced by hadronic vacuum polarization.

Orateur: Letizia Parato (Aix-Marseille Université)

LetiziaJRJC2.pdf

17:00 Recasting Direct Detection Limits Within MicrOMEGAs And Implication For Non-Standard Dark Matter Scenarios

Direct detection experiments present 90% exclusion cross-sections for point-like spin-independent Dark Matter interaction with nucleons for fixed cosmological parameters. In this presentation, we discuss a possibility to extend obtained results of such experiments on model with arbitrary cosmological parameters, different form factors of spin-dependent interaction, interactions via light t-channel mediator, millicharged DM.

Orateur: Ali Mjallal (LAPTh)

JRJC presentation.pdf

17:30 Dark matter searches towards WLM dwarf irregular galaxy with H.E.S.S.

In the indirect dark matter (DM) detection framework, the DM particles would produce some signals by self-annihilating and creating standard model products such as $\gamma$ rays, which might be detected by ground-based telescopes.
Dwarf irregular galaxies represent promising targets for the search for DM as they are assumed to be dark matter dominated.
In 2018, the H.E.S.S. telescopes observed the irregular dwarf galaxy Wolf-Lundmark-Melotte (WLM) for 18 hours. These observations are the very first ones made by an imaging air Cherenkov telescope toward this kind of objects. We search for a DM signal looking for excess of $\gamma$ rays towards WLM dwarf galaxy. We perform the first analysis of this source in stereoscopy using the data taken by the five H.E.S.S. telescopes. We present the new results on the observations of WLM interpreted in terms of velocity-weighted cross section for DM self-annihilation $\langle\sigma v\rangle$ as a function of DM particle $m_{\chi}$ mass for several annihilation channels.

Orateur: Celine Armand (LAPP & LAPTh)

CelineJRJC_2019_WLM_dwarf galaxy.pdf

19:30 → 21:30 Diner

mardi 26 novembre

09:00 → 10:30 Astroparticle: Session I

Président de session: Romain Gaior (LPNHE)

09:00 Introduction Astroparticule / Cosmologie

Orateur: Romain Gaior (LPNHE)

intro_astrocosmo.pdf

09:30 The Search for Light Dark Matter with DAMIC

The DAMIC (Dark Matter in CCDs) experiment employs the bulk silicon of scientific-grade charge coupled devices (CCDs) to detect dark matter particles. Since 2017, DAMIC has operated a seven-CCD detector (40-gram target mass) installed in a low radiation environment in the SNOLAB underground laboratory. The CCDs have excellent energy and spatial resolutions, low-energy threshold and unique capability to identify surface and bulk radioactive backgrounds. The DAMIC-M Experiment, the next phase of the program, will be installed at the Laboratoire Souterrain de Modane in France. It will feature a kg-size silicon target consisting of ultra low-noise CCDs, and will probe a broad range of low-mass dark matter particles. DAMIC-M CCDs feature a new specialized Skipper readout and have unprecedented single electron resolution resulting in a detection threshold as low as 2 ionized electrons. I will present results from the DAMIC Experiment at SNOLAB, and will review key development efforts of DAMIC-M, including the characterization of our first batch of 24 mega-pixel Skipper CCDs, the largest ever built.

Orateur: Ariel Matalon (University of Chicago; LPNHE)

JRJC_Talk_Matalon.pdf

10:00 Development and characterization of novel electronics for the search of dark matter for DAMIC-M

Despite plenty of evidence for the existence of Dark Matter (DM), no experiment has ever managed to capture it directly. In the last decades, the Weakly Interacting Massive Particle (WIMP) paradigm, the most popular among the DM models, has proven unsuccessful experimentally in a variety of detection methods in the GeV-TeV mass range. DAMIC-M (DArk Matter In CCDs at Modane) will aim to directly search for light WIMPs (<10 GeV) and hidden-sector DM, using a tower of scientific-grade Charge-Coupled Devices (CCDs) of a kg-size total target mass. In addition, by implementing the Skipper readout technique, a sub-electron energy resolution can be achieved. A critical feature of this undertaking will be the development of an acquisition system for the overall control and readout of the CCDs. I will present preliminary results from the evaluation of novel readout electronics including the front-end CCD ReadOut Chip (CROC), which will provide a pre-amplification on the output signal and improve the Signal-to-Noise Ratio, and a new Analog-to-Digital Converter board, allowing for a fast and high-resolution data acquisition.

Orateur: Georgios PAPADOPOULOS (LPNHE)

Georgios PAPADOPOULOS_JRJC2019_26Nov2019.pdf

10:30 → 11:00 Coffee break

11:00 → 12:30 Astroparticle: Session II

Président de session: Romain Gaior (LPNHE)

11:00 Reducing coating thermal noises in Gravitational wave detectors using AlGaAs crystalline mirrors

The first gravitational wave detections occured with the LIGO detector in the United states and the Virgo detector in Europe, opening the way to the field of gravitational astronomy and providing informations on black holes, neuton stars and relativity theory of Einstein that were inaccessible before. These detectors are based on giant laser interferometers several kilometers long. It is essential to improve their sensitivity to progress in this area.

One of the main limitation of the sensitivity comes from the thermal fluctuation that occurs within the mirrors used in these giant laser interferometers. This fluctuation depends on the temperature and is known as thermal noise. Detailed studies show that the main cause is the reflective multilayer coating deposited on the surface of the mirror.

The goal of this research is to develop new mirrors based on monocrystalline coatings to reduce thermal noise and improve the sensitivity of gravitational wave detectors. More precisely, the project comprises the production of crystalline mirrors based on GaAs / AlGaAs stacks as well as their optical and mechanical characterization.

Orateur: Victor Hui (LAPP)

Présentation JRJC.pdf

11:30 Optimisation of the optical follow up of gravitationnal waves events

The third LIGO-Virgo run (O3) started the first of April and multi-messenger astronomy related to gravitational waves with it. Gravitational waves from binary neutron star (BNS) coalescence, in association to short gamma-ray burst, opened a new era of multi-messenger astronomy. The identification of the counterpart and it’s multi-wavelength observations improved our understanding of the physics of strong-gravity and put some constraints on astrophysical models related to matter during the merger and post-merger phase. With improved sensitivity of the LIGO-Virgo detectors, the year-long third observing run (O3) promises many merging binaries with an expected number of BNS mergers in the range 1-50. Therefore an intensive multi-wavelength follow-up of those event with ground and space instruments is performed all around the world.
But the identification of the electromagnetic counterpart of such event is very challenging knowing the wide sky localization area provided by LIGO-Virgo and require complex observation strategies implying many telescopes. We will present our recent development on such strategies, from selections of galaxies to optimisation of telescope networks observations.

Orateur: Jean-Grégoire Ducoin (LAL - Virgo)

JRJC_2019_Ducoin.pdf

12:00 The hunt for VHE gamma-rays in the Gravitational Waves era.

In multi-messenger astrophysics, we combine different astronomical messengers in order to study different aspects of an object or a process in the Universe. Nowadays, four astronomical messengers exist: electromagnetic waves, cosmic rays, neutrinos and Gravitational Waves (GW). The first direct discovery of GW emitted from the inward spiral of two black holes in 2015 took multi-messenger astrophysics to the next level, adding direct detection of GW to the list of messengers coming from the sky. Almost two years later, the first detection of GW from a binary neutron star merger alongside electromagnetic counterparts in several bands started a new era in multi-messenger astrophysics triggering worldwide search programs for GW counterparts. Very High Energy (VHE) gamma-rays covers the highest band in the electromagnetic spectrum and provides valuable information for the characterization of astrophysical phenomena. This is why the search for VHE gamma-ray from GW events is in the heart of these search campaigns. In this contribution I report on GW follow-up program with the H.E.S.S. Imaging Atmospheric Cherenkov Telescopes and its outcome until now.

Orateur: Halim Ashkar (CEA-Irfu)

ASHKAR_JRJC_compressed.pdf

12:30 → 15:00 Lunch

15:00 → 16:30 Astroparticle: Session III (Cosmology)

Président de session: Romain Gaior (LPNHE)

15:00 Development of an advanced Compton telescope prototype for MeV-range gamma-ray astronomy

An advanced Compton telescope appears to be the best instrument concept for the next generation gamma-ray space observatory in the MeV range. A first prototype of advanced Compton telescope is being developed to match the constraints of a nano-satellite mission, with the scientific objective of measuring gamma-ray burst prompt emission polarization. Instrumental developments at CSNSM for this project are focusing on the position-sensitive calorimeter module with a monolithic scintillator and pixelated photodetectors. The 3D position of interacting gamma rays is obtained with deep learning alogrithms. In a second part of the study, simulations will be performed to assess the imaging and polarimetric capabilities of the nano-satellite's instrument. We will also make test measurements with the prototype, as part of a particle accelerator experiment or during a stratospheric balloon flight.

Orateur: M. Adrien LAVIRON (CSNSM, Université Paris-Sud/CNRS IN2P3)

jrjc19_v3.pdf

15:30 StarTrack predictions of the stochastic gravitationnal-wave background from compact binary coalescences

In this study we evaluate the contribution of binary coalescences to the stochastic gravitationnal-wave background from population 1, 2 and 3, as defined by to the hertzsprung Russel classification. We assume that the coalescences we observed are formed throug stellar evolution in the field of galaxies with no dynamical interactions. We use the new population synthesis starTrack to generate realistic population of merging binaries (binary black holes BBH, but also binary neutron stars and neutron star-blackholes), and calculate the energy density spectrum of the background. We account for the eccentricity, which is expected to play a signifiant role at low frequencies accessible by the space antenna LISA. In addition, for the first time, we include binaries that do not merge in a Hubble time. We obtain the energy density contributions for all of these populations and also the residual contributions, after detected sources are subtracted by four detector networks: HLV (LIGO Hanford and Livingstone and Virgo), HLVIK (HLV and LIGO India and Kagra), ET (Einstein Telescope), and ET+2CE (ET and two cosmic explorer located at the actual place of Hanford and Livingston).

Orateur: Carole Perigois

16:00 Using simulated quasar catalogs for the BAO in lyman-$\alpha$ analysis of eBOSS and DESI

The accelerated expansion of the universe caused by the presence of dark energy was first observed in 1998 by measurement of the luminosity of type Ia supernovae. In 2005, a new probe for dark energy, the Baryon Acoustic Oscillation (BAO) was introduced. This probe is based on the imprint left in the matter density field by sound waves propagating in the primordial universe. Following the initial detection of this BAO signal, several surveys, including eBOSS and its successor DESI, have been designed to measure this signal in the quasar and galaxy distribution through the computation of their correlation function.
Quasars with redshift higher than 2 have in their spectra a collection of absorption lines called the lyman-$\alpha$ forest. These absorptions stem from the presence of neutral hydrogen clouds along the line of sight of the quasar. Each of these absorption lines are mass tracers that can be used to calculate the correlation function. Neutral hydrogen clouds with column density above $2*\log20\ cm^{-2}$ are called Damped Lyman-$\alpha$ Absorbers (DLAs). Their presence in quasar spectra skews the calculation of the correlation function and has to be addressed. Hitherto DLAs in data are identified by a DLA finder algorithm and masked out of the forest.
My work focuses on studying the impact masking the DLAs has on the measured cosmological parameters. I will present results using simulated quasar spectra catalogs with different masking strategies to determine the efficiency of this method.

Orateur: Julianna Stermer (LPNHE)

Stermer JRJC 2019.pdf

16:30 → 17:00 Coffee break

17:00 → 19:00 Standard Model: Session I

Président de session: Reina Camacho Toro (LPNHE)

17:00 Introduction to the Standard Model session

Orateur: Reina Camacho Toro (LPNHE)

JRJC2019_SMIntro_Camacho.pdf

17:30 Measuring quantum interference in the off-shell Higgs with Machine Learning

The traditional methods of training a classifier to separate signal and background events for measurement break down in the context of quantum interference between signal and background processes. How can we train a Machine Learning model without the concept of labels?

New statistical approaches were developed and machine learning approaches are being investigated to solve this problem, which, if successful, would enhance the sensitivity to the signal strength of the QFT processes due to an off-shell Higgs boson. Advantages might include an optimal method for various values of the signal strength, even far away from the standard model value, as well as the possibility to have a machine learning method be aware of certain systematic uncertainties.

Orateur: Aishik Ghosh (LAL)

JRJC_26Nov2019.pdf

18:00 Forward Jet Vertex Tagging in ATLAS using the particle flow algorithm

Orateur: Anastasia Kotsokechagia

JRJC.pdf

18:30 Towards the first observation of the simultaneous production of four top quarks with the ATLAS detector

The topic of this contribution belongs to the field of high energy particle physics (HEP), which is the part of physics dealing with the question: “What are the fundamental building blocks of nature and how do they interact?”

The theoretical framework of this field is called the standard model of particle physics (SM), which is an incredibly powerful framework resulting in very precise predictions and it has been tested and validated in a large variety of different experiments over the course of its existence.
Even though the SM already covers a very broad spectrum in HEP, a few major phenomenae, such as gravity or dark matter, are not yet accounted for. To incorporate these processes not yet described by the SM, is one of the goals of beyond standard model (BSM) theories.

Seeing that there are a plethora of possibly valid BSM theories, it is the task of experimentalists to find and study processes that have a differently predicted outcome for the SM or BSM theories, which would allow for a verification or falsification of the corresponding models.

Among such processes, those involving a top quark play an important role due to the quark’s elevated mass and its corresponding short decay time, which inhibits the forming of compound states for this particle. Within this group of top quark related processes, a particularly interesting process is the simultaneous production of four top quarks, since it involves a very high centre-of-mass energy, it has not yet been observed and because the probability of occurrence predicted by the SM and BSM theories differ enormously.
All this makes its discovery, or non-discovery, a very important goal for the HEP community.

During this contribution a broad introduction to the field and the ongoing search for the simultaneous production of four top quarks by the ATLAS collaboration will be given.

Orateur: Lennart Rustige

2019-11-26_RUSTIGE_4top.pdf

19:30 → 21:30 Diner

mercredi 27 novembre

09:00 → 10:30 Hadronic physics: Session I

Président de session: Maxime Guilbaud (SUBATECH)

09:00 Hadronic session introduction

Orateur: Maxime Guilbaud (IPNL)

09:30 Inclusive J/ψ production in pp and Pb-Pb collisions at forward rapidity at √s NN = 5.02 TeV in ALICE at the LHC

The ALICE Collaboration focuses on studying the matter at extremely high temperature and density created by heavy-ion collisions in the laboratory. This state of matter is called quark-gluon plasma (QGP) and is made of deconfined quarks and gluons. The QGP is thought to exist for the first few microseconds after the Big Bang. During the collision, many particles are produced, in particular the charmonia, bound states of elementary particles, charm quarks and antiquarks. The J/ψ, one of the charmonium states, is considered as a probe of the QGP properties. In the QGP phase and if the temperature is large enough, the J/ψ is predicted to be dissociated because of a mechanism called color screening. Indeed the high density of color charges in the deconfined medium can screen the interquark potential and prevent the formation of the bound state. This is known as J/ψ melting. On the other hand, at LHC colliding energy, another mechanism of J/ψ production can be considered. Since the production cross section of charm-anticharm quark pairs is large, charmonia (including J/ψ) can be formed in or at the end of the QGP phase, from uncorrelated deconfined charm and anticharm quarks. This is called the regeneration mechanism. To study the J/ψ yield modifications by the hot medium effects in heavy-ion collisions, one physical observable is measured, which is the nuclear modification factor $R_{AA}$. Precisely, $R_{AA}$ is the ratio of J/ψ yield in heavy-ion and nucleon-nucleon collisions, scaled by a normalization factor, the number of binary nucleon-nucleon collisions. In this talk, we report on the J/ψ $R_{AA}$ measurement as a function of transverse momentum ($p_{T}$ ) in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02 TeV, and on the J/ψ reference cross section measurement in pp collisions at the same energy. The measurement is performed in the dimuon decay channel with ALICE muon spectrometer. These new data in Pb-Pb and pp collisions, corresponding to the LHC Run2 statistics, allow one to extend the previous $R_{AA}$, pp cross section up to $p_{T}$ = 20 GeV/c, and to study the $R_{AA}$ multi-differentially in $p_{T}$, rapidity (y) and centrality.

Orateur: Chun Lu Huang (IPNO)

JRJC_2019_Slides_HUANG.pdf

10:00 B_c meson production measurement in pp and PbPb collisions with CMS

Heavy (beauty and charm) quarks are very valuable probes of the quark-gluon plasma created in heavy ion collisions, because they experience the whole evolution of the medium. They can also help understanding the dynamics of hadronization, and how they are affected by the interaction with the medium. In this context, the B_c meson is an interesting and new probe, that could both give new insights on beauty and charm quarks energy loss, and on the charm recombination mechanism.
This talk shows the progress of the first study of the B_c meson in heavy ion collisions, namely in 2018 PbPb data from CMS at sqrt(s_NN) = 5TeV. The equivalent study in 2017 pp reference data at 5TeV is more advanced, and used as a benchmark for the PbPb analysis. Ultimately, the ratio of cross sections is to be calculated, to be interpreted as the nuclear modification factor of B_c in the plasma.

Orateurs: M. Guillaume Falmagne (LLR), Guillaume Falmagne

JRJC 26.11.2019.pdf

10:30 → 11:00 Coffee break

11:00 → 12:30 Hadronic physics

11:00 Quarkonium anisotropic flow in Pb-Pb collisions with ALICE

ALICE experiment at LHC studies through ultra-relativistic heavy ion collisions, a deconfined state of matter, the Quark Gluon Plasma (QGP). This state raises many questions about mechanisms of strong interaction and the cohesion of matter. Moreover, QGP is an extremely hot and dense state that behaves more like a nearly ideal, strongly interacting fluid and it can represents the universe at the first microseconds. According to Quantum Chromodynamics (QCD) the theory that describes strong interaction, heavy quark pair (quarkonium) represent an ideal probe to study such a state. Thus, the measurement of quarkonium azimuthal anisotropy in the particle distributions (related to the anisotropic flow), at an energy in the center of mass at 5.02 TeV, will allow to constrain the transport models describing the quarkonium production and the macroscopic properties of the QGP.

Orateur: Robin Caron (Université Paris-Saclay (FR))

JRJC_talk_rcaron.pdf

11:30 Measurement of an excess in the yield of J/ψ at very low pT in Pb-Pb collisions at 5.02 TeV with ALICE

In 2015, the ALICE collaboration reported the first excess in the yield of $J/\psi$ at very low transverse momentum ($p_T<0.3\ GeV/c$) in the forward rapidity region ($ 2.5 < y <4 $) in peripheral Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV at the CERN LHC. [1] The coherent photo-production was proposed as the potential underlying physics mechanism. This mechanism is the main responsible for low-$p_T$ $J/\psi$ production in ultra-peripheral collisions but was never observed in more central collisions that are dominated by the hadronic interactions.
If the photo-production is confirmed as the origin of the excess, this will open up fundamental questions on the nature of the coherence in collisions with nuclear overlap. Furthermore, the $J/\psi$ from the coherent photo-production could become a new probe of the Quark and Gluon Plasma.

References

[1] ALICE Collaboration, J. Adam et al., “Measurement of an excess in the yield of $J/\psi$ at very low $p_T$ in Pb-Pb collisions at $\sqrt{s_{NN}} = 2.76$ TeV", Phys.Rev.Lett.116(2016) 222301, arXiv:1509.08802 [nucl-ex].

Orateur: Ophélie Bugnon

OBugnon_JRJC2019.pdf

12:00 Weak boson production in p-Pb at 8.16 TeV with ALICE

The measurement of the Z and W production cross sections in heavy-ion collisions allow to probe the internal structure of the nucleus and constrain the nuclear Partonic Distribution Functions. The work presented here is based on data from proton$-$lead collisions at $\sqrt{s_{_{\rm NN}}}$ = 8.16 TeV recorded with ALICE.

Orateur: Guillaume Taillepied (LPC Clermont)

20191128_jrjc_Z_and_W_pPb_8tev_indico.pdf

12:30 → 15:00 Lunch

15:00 → 16:00 Neutrino physics

15:00 Introduction to Neutrino Physics

Orateur: Laura Zambelli (LAPP)

neutrino_intro_2019.pdf

15:30 ProtoDUNE Dual-Phase Liquid Argon TPC

The Deep Underground Neutrino Experiment (DUNE) is a long-baseline project that will study an accelerator-made neutrino beam produced at Fermilab. DUNE will consist of two detectors placed in the path of the neutrino beam, one near the source and one at the Stanford Underground Research Facility, at a distance of 1300km and protected by a 1500m rock overburden. Fundamental features of neutrino oscillation physics, such as leptonic CP violation and the mass hierarchy, as well as supernovae and proton decay physics, will be studied with high precision during more than 10 years of data taking, starting in 2026. The far detector technology consists of four 60m x 12m x 12m liquid argon time projection chambers (LArTPC). Each module contains 10kt of fiducial mass and will be able to reconstruct the 3-dimensional trajectories of charged particles passing through argon. Two designs are currently proposed for the far detector modules: one with only liquid argon (Single-Phase), the other containing a small volume of gaseous argon at the top of the active volume (Dual-Phase). The latter includes an electron multiplier device designed to increase the ionization signal before its collection. Both designs are currently being tested with 6m x 6m x 6m active volume prototypes at CERN. My PhD is centered on the Dual-Phase technology and in particular the development of signal and trajectory reconstruction algorithms created or adapted for its unique features.

Orateur: M. Etienne Chardonnet (Laboratoire APC, Université Paris Diderot)

Presentation_JRJC2019.pdf

16:00 → 16:30 Coffee break

16:30 → 17:30 Neutrino physics

16:30 Modeling of reactor antineutrino spectrum

Nuclear reactors are intense antineutrino emitters and are therefore useful sources to study the fundamental properties of the neutrino. Antineutrino spectra and fluxes measured in past experiments at reactor sites have showed deviations from the models, confirmed by last generation experiments, whose origin remains unclear. The goal of my PhD thesis is to revisit the theoretical models to adress the origin of these anomalies. Reactor antineutrino are produced by successive β- decays of neutron-rich fission products originating from the fission of 235U, 238U, 239Pu, 241Pu in the core. The nucleus emits then an electron in correlation with an antineutrino. The total antineutrino spectrum of a reactor core is made of the superposition of thousand of β spectra. A code named BESTIOLE (Beta Energy Spectrum Tool for an Improved Optimal List of Elements) is being updated to model each fission product β decays and to revisit the summation method. This method sums all the β branches listed in modern nuclear databases to predict the β and antineutrino spectra emitted by a nuclear reactor. In this talk I will present a new and preliminary computation of a reactor antineutrino spectrum using this method together with a refined modeling of β- decay. The portion of the spectrum below 1.8 MeV, which is relevant to the study of coherent elastic neutrino-nucleus scattering at reactors, has also been investigated.

Orateur: M. Lorenzo Périssé (CEA/Irfu)

JRJC_2019_LP.pdf

17:00 Recherche d'un neutrino stérile au réacteur de l'ILL-Grenoble avec STEREO

Au cours des dernières décennies, les expériences neutrino auprès des réacteurs nucléaires ont fait progresser la connaissance des oscillations de neutrino, notamment avec une mesure précise de l’angle de mélange 13. Cependant, une anomalie concernant le flux d’antineutrinos émis par les réacteurs attend encore d’être résolue, le déficit observé nommé Reactor Antineutrino Anomaly (RAA) peut être expliqué par l’existence d’un état stérile du neutrino participant à l’oscillation. Les valeurs des paramètres d’oscillation expliquant au mieux la RAA sont sin2(2new) =0.14 et m241 =2.4 eV2 . 
L’expérience STEREO a été conçue dans le but de vérifier l’hypothèse d’oscillation vers un neutrino stérile. Elle mesure le flux et le spectre d’antineutrinos émis par le cœur compact du réacteur de recherche de l’institut Laue-Langevin à Grenoble. La cible, segmentée en 6 cellules, du détecteur placé à 10 m du cœur permet une mesure du spectre à différentes distances. Une oscillation vers un état stérile pourrait être détectée car elle induirait une distorsion différente du spectre en énergie dans chaque cellule.
La prise de donnée ayant commencé à la fin de l’année 2016, la collaboration STEREO a publié ses premiers résultats en 2018 excluant une zone significative de l’espace des paramètres et rejetant les valeurs des paramètres préférés pour la RAA avec un intervalle de confiance à 99%.

During the last decades, reactor neutrino experiments allowed us to characterize the neutrino oscillations, in particular the mixing angle 13 has been precisely measured. However, a discrepancy between the antineutrino flux observed and expected, known as Reactor Antineutrino Anomaly (RAA), has yet to be solved. This anomaly could be due to the existence of a sterile neutrino state participating in the oscillation. The parameters value that best fit this oscillation are : sin2(2new) =0.14 and m2 41 =2.4 eV2 .
The STEREO experiment was designed to test this oscillation hypothesis, by measuring the flux and energy spectrum of antineutrinos emitted by the compact research reactor core of the Laue-Langevin institute (Grenoble, France). 
The target, segmented in six cells and located at about 10 m from the reactor core, allows for a measurement of the energy spectrum at various baselines. The oscillation toward a sterile neutrino could be detected as it would distort each cell’s spectrum differently. 
Ongoing data taking has begun in 2016. In 2018 the STEREO collaboration published its first results excluding a significant part of the parameter space and excluding the RAA best fit with a confidence level of 99%.

Orateur: Loic Labit (LAPP)

JRJC_2019_talk_LoicLabitLQ.pdf

19:30 → 21:30 Gala Dinner

jeudi 28 novembre

10:00 → 11:00 Nuclear physics: Session II

Président de session: Dr Diego Gruyer (LPC Caen)

10:00 Introduction physique nucléaire

Orateur: Diego Gruyer (LPC Caen)

short.pdf

10:30 Étude des corrélations neutron-neutron dans le noyau de 12Be

The very interesting nucleus of 12Be is studied using the proton knock-out reaction on 13B at GSI. This reaction populates both bound and unbound states in 12Be. The experimental set-up is a combined detection of gamma, neutron and charged fragments with good efficiencies.

The inverse kinematics method was used to reconstruct the decay energy and we can study decay modes of the states in 12Be. Moreover, some of the states are above the 2n emission threshold and are then pair emitters. neutron-neutron correlation are investigated using the method of Dalitz plots.

Orateur: Armel KAMENYERO (GANIL)

JRJC_12Be.pdf

11:00 → 11:30 Coffee break

11:30 → 12:30 Nuclear physics: Session III

Président de session: Diego Gruyer (LPC Caen)

11:30 UNDERSTANDING COSMIC ABUNDANCE OF 22Na

Simulation of nova explosive nucleosynthesis at the white-dwarf surface predicts the production of the radionuclide $^{22}$Na. It has an interesting half life of 2.6 yr, making it a potential astronomical observable by allowing space time correlation with the astrophysical object. $^{22}$Na should provide constraints on nova models, but its gamma-ray line 1.275 MeV has not been observed yet. Within nova temperature range, the main destruction reaction $^{22}$Na(p,$\gamma$)$^{23}$Mg is dominated by a resonance at 0.213 MeV corresponding to $^{23}$Mg excited level 7.786 MeV, as it will be shown here. There is however a disagreement among the measured strengths of this resonance. An experiment was performed at GANIL facility to measure the lifetime of 7.786 MeV level with a resolution expected at 1 fs (known upper limit 12 fs). The experiment will be presented. With a beam energy of 4.6MeV/u, the neutron transfer reaction $^{3}$He($^{24}$Mg,$\alpha$)$^{23}$Mg$^*$ at state of interest was tagged with particle detectors (VAMOS++ spectrometer, SPIDER silicon dE-E)and gamma tracking spectrometer AGATA. The resolution of order 1 fs is possible with Doppler Shift Attenuation Method DSAM, meaning an analysis of Doppler shifted attenuated lineshapes of measured gamma peaks. The experiment will also allow an evaluation of the branching ratio for proton decay of $^{23}$Mg interesting state. In fine, $^{22}$Na(p,$\gamma$)$^{23}$Mg resonance strength $\omega \gamma$ will be obtained with higher precision. Predictions of the impact of this resonance on $^{22}$Na abundance in nova ejecta will be presented.
Preliminary results of the experiment analysis will be presented. Produced light particles have been identified within SPIDER data as well as gamma Doppler shifted rays from $^{23}$Mg excited states. Preliminary constrains thanks to $\alpha$ coincidence seen by VAMOS have allowed to improve gamma spectra. Velocity of $^{23}$Mg ions has been estimated with a Doppler correction method presented here. A first estimation of the known lifetime of $^{23}$Mg at 2.052 MeV has been derived through DSAM with a preliminary Monte Carlo simulation of the experiment.

Orateur: Mlle Chloé Fougères (GANIL CEA/DRF - CNRS/IN2P3)

JRJC_2019_PDF_CFOUGERES.pdf

12:00 Transport d'isospin dans les collisions nucléaires étudié avec les multidétecteurs INDRA-FAZIA

Les collisions d'ions lourds autour de l'énergie de Fermi sont largement utilisées pour étudier l'équation d'état de la matière nucléaire; les réactions nucléaires dissipatives permettent en effet un transfert important d'énergie et de matière entre le projectile et la cible, et donc l'étude de noyaux fortement comprimés, excités, en rotation et possédant éventuellement une richesse plus ou moins grande en neutrons : c'est la composition isotopique des produits de réaction, que l'on caractérise expérimentalement par le rapport N sur Z (isospin) du fragment détecté. La dépendance de l'équation d'état en fonction de l'isospin est regroupée sous le terme d'énergie de symétrie. L'énergie de symétrie a un impact important sur les caractéristiques des noyaux riches en neutrons notamment, qui sont en grande partie à l'origine de la synthèse des noyaux plus lourds que le Fer dans les processus stellaires.
En collisionnant des noyaux accélérés au GANIL on espère chauffer suffisamment la matière nucléaire pour observer une transition de phase entre le liquide nucléaire et un gaz de nucléons et de fragments. Le rôle de l'isospin avait été jusqu'ici peu étudié pour comprendre les mécanismes de réaction et l'évolution thermodynamique des noyaux chauds ainsi formés (notamment la dépendance en isospin).
L'utilisation de projectiles et de cibles d'isospins différents permettent de sonder l'influence de l'isospin sur la compressibilité de la matière nucléaire, donc l'évolution de l'énergie de symétrie en fonction de la densité. Ce type d'étude doit aussi permettre la caractérisation des processus d'équilibration en isospin et obtenir une meilleure compréhension du transport de l'isospin dans les collisions d'ions lourds. Il est aussi possible d'étudier l'influence de l'isospin sur les processus de désexcitation des noyaux chauds afin de mieux comprendre la dépendance isovectorielle de l'équation d'état de la matière nucléaire.
La collaboration FAZIA a développé un détecteur capable de mesurer la charge et la masse des fragments avec une résolution comparable à celle d'un spectromètre de masse magnétique mais aussi avec une couverture angulaire beaucoup plus importante jusqu'à Z=25 avec une excellente résolution en énergie. Pour l'expérience de cette thèse, douze blocs de FAZIA ont été installés au GANIL dans la chambre à vide d'INDRA. FAZIA a été couplé à une partie du multi-détecteur plus ancien INDRA. Ce dernier identifie en charge et en masse jusqu'à Z=8 et uniquement en charge jusqu'à Z = 92. Ce couplage offre une couverture angulaire de 80\% de l'angle solide (1,5° à 14° pour FAZIA, 14° à 176° pour INDRA).
Cette présentation décrira d'abord la diffusion d'isospin, son intérêt et les différents processus intervenant dans les collisions nucléaires. Elle se concentrera ensuite sur la mise en place de la première expérience INDRA-FAZIA au GANIL.

Orateur: M. Joël Quicray (Laboratoire de Physique Corpusculaire de Caen)

JRJCJoelQuicray.pdf

12:30 → 14:00 Lunch

14:00 → 15:30 Nuclear physics: Session IV

Président de session: Diego Gruyer (LPC Caen)

14:00 Detection of the decay of laser oriented trapped radioactive isotopes for the MORA Project

The MORA (Matter's origin from the Radioactivity of trapped and oriented ions) project focuses on the measurement of D correlation parameter in the nuclear beta decay of trapped and oriented ions. The D correlation offers the possibility to search for new CP-violating interactions at much higher level than predicted by the standard model.
Technically, MORA utilizes an innovative in-trap orientation method combining the high trapping efficiency of a Paul trap with laser orientation techniques by exposing the confined ion cloud to circularly polarized laser light. Currently, the trapping, detection and laser setups are under development.
The MORA setup dedicated for the trapping is inspired from the Paul trap of the LPCTrap experiment which has a trapping capacity of ${5.10^5}$ ions along with trapping lifetime limited so far to 0.5 s. With an optimized geometry and RF system, we expect the trap of MORA should enable cycle times of the order of a few s.
This project will first focus on the proof-of-principle of the in-trap laser orientation technique and then on the measurement of D correlation in the decay of $^{23}Mg^{+ }$ ions at JYFL(Finland) and in GANIL(Caen). In my talk, I would be briefly discussing the motivation and related physics.

Orateur: Nishu GOYAL (Ganil)

14:30 Développement d’un module tout-en-un d’activation neutronique intégré à RayXpert, logiciel de modélisations CAO et Monte-Carlo

Dans les installations nucléaires où sont générés des neutrons, les matériaux sont activés par les particules faisant des interactions nucléaires. En particulier, les neutrons n’étant pas chargés, ils ne subissent pas l’interaction électromagnétique. Ils sont alors susceptibles de causer des réactions nucléaires même à faible énergie. Ces interactions génèrent un phénomène appelé activation neutronique : il consiste en l’apparition d’isotopes instables dans les matériaux proches d’une source de neutrons. Ces isotopes instables générés dans les matériaux activés produisent lors de leurs décroissances des rayonnements qui peuvent être nocifs pour l’Homme. Or, ces décroissances peuvent perdurer durant des périodes supérieures à des décennies. Afin de réaliser des opérations de maintenance en toute sécurité, de prédire comment effectuer le démantèlement d’une installation nucléaire ou encore de définir au mieux comment élaborer une installation nucléaire, il est nécessaire de modéliser correctement les effets dus aux neutrons.
La modélisation des effets dus aux neutrons est généralement réalisée en différentes étapes. La première étape consiste à calculer le flux neutronique par la méthode Monte-Carlo sur un maillage suffisamment fin de la géométrie réelle à l’aide d’un code tel que MCNP [1]. Puis, le calcul de l’évolution de l’inventaire isotopique est effectué pour chaque maille élémentaire. Enfin, les sources de décroissances sont utilisées pour propager les particules issues de ces décroissances dans la géométrie. Ce transport est généralement effectué par une méthode Monte-Carlo et permet de calculer le flux de particules de décroissance sur un maillage superposé à la géométrie. Enfin, des facteurs de conversion flux vers dose [2] permettent de transformer le flux de particules en dose. Le transport des particules est effectué avec un code de calcul Monte-Carlo et le calcul de l’inventaire avec un code de calcul d’inventaire isotopique tel que FISPACT II [3]. La simulation des doses résiduelles dans une installation nucléaire où des neutrons ont été produits est donc un processus compliqué nécessitant à minima 2 calculs Monte-Carlo ayant un fort coup numérique en plus d’un couplage entre différents codes de calculs.
Les objectifs du travail sont donc multiples. Dans un premier temps, il est envisagé de réaliser un module tout-en-un capable de simuler les doses résiduelles dans une installation nucléaire où des neutrons ont été produits. Ce module sera intégré à RayXpert [4], logiciel de CAO et de suivi de particules par méthode Monte-Carlo développé à TRAD. Le module permettra alors en un clic de réaliser toutes les étapes précédentes et de gérer l’enchainement des étapes susmentionnées. Dans un second temps, diverses optimisations sont envisagées afin d’accélérer les calculs Monte-Carlo qui nécessitent généralement de longues durées afin de fournir des résultats fiables.

[1] C.J. Werner, J.S. Bull, C.J. Solomon, et al.,,"MCNP6.2 Release Notes", LA-UR-18-20808 (2018).
[2] ANSI/ANS-6.1.1 Working Group, M.E. Battat, American National Standard Neutron and Gamma-Ray Flux-to-Dose Rate Factors, ANSI/ANS-6.1.1- (N666), American Nuclear Society, LaGrange Park, IL, 1977, p. 1977
[3] J.-Ch. Sublet and al., FISPACT-II: An Advanced Simulation System for Activation, Transmutation andMaterial Modelling, Nuclear Data Sheets 139 (2017) 77-137
[4] RayXpert Manuel Utilisateur, TRAD/DL/DOS/RAYXPERT/CD/110412 Rev13, 20/11/2017

Orateur: M. Nicolas Dray (LPT IRSAMC)

15:00 High energy PIXE: K-shell ionization cross sections for titanium, copper and silver atoms and comparison with theoretical values of RECPSSR model

A platform was implemented on ARRONAX to perform non-destructive materials analysis with X rays emission induced by high energy beams (HEPIXE). The HEPIXE has already been used to analyze geological samples and thick objects such as old paintings and coins in the field of art.
One of the benefits of HEPIXE is the significant increase of the K-lines X-ray production cross-sections of medium and heavy elements with respect to those of lower energy protons. This makes possible the identification of these elements with K-X rays. HEPIXE is adapted for the analysis of thick targets particularly if the bulk composition is different from the composition of the surface.

The knowledge of the K-Shell ionization cross sections is necessary to perform quantitative analysis with PIXE. Currently, experimental data available at high energy are scarce.

An experimental campaign has been conducted at the ARRONAX cyclotron to measure the K-X ray production cross-sections of titanium, copper and silver atoms in a wide energy range from 30 MeV to 68 MeV.

The parameters of the experimental devices such as the detector efficiency, the beam intensity, and the targets thicknesses, have been characterized accurately in order to obtain precise measurements. Special care has been made to select the most accurate K-shell fluorescence yields from the literature data, in order to convert the K X-ray production cross sections to the K shell ionization cross section.

We will present, a review of the theoretical model RECPSSR, followed by a description of our experiment (beam, detector, and target). The outcomes of the experiment will be compared with the existing data and the theoretical predictions of model.

Orateur: M. Quentin MOUCHARD (SUBATECH, IMT Atlantique)

15:30 → 16:00 Coffee break

16:00 → 17:30 Invited speaker

Association Terre & Ocean qui s'occupe de la médiation culturelle des sciences liées aux environnements terrestre et aquatique dans la région. http://www.terreetocean.fr

16:00 Évaluer les effets des débris plastiques sur les écosystèmesmarins :un challenge en pleine évolution !

La pollution plastique marine est un problème environnemental majeur. Compte tenu de leur omniprésence dans les océans et, pour certains de leurs petites dimensions, l'ingestion de particules de microplastiques (MP) et de nanoplastiques (NP) et leur impact ultérieur sur la vie marine suscitent de plus en plus d'inquiétude. Même si toutes les clés de compréhension des phénomènes ne sont pas encore connues, les transferts le long de la chaîne trophique, le déplacement éventuel de ces microparticules, porteuses de polluants et/ou d’espèces invasives voire pathogènes constituent une préoccupation majeure dans le monde scientifique. Une partie de ces problématiques a été abordée au cours de différents projets de recherche menés au sein du Laboratoire des Sciences de l’environnement marins (LEMAR) à Brest et notamment: l’évaluation de la contamination en microplastiques de la Rade de Brest; la colonisation des microplastiques présents en Rade par des bactéries; les effets de l'ingestion de MP sur des huîtres, des moules ou des larves de poissons (bars), l’effet de nanoparticules de plastique sur les gamètes d’huîtres (ovocytes et spermatozoïdes)... Les résultats obtenus à l’issu de ces expositions sont une source d’inquiétudes légitimes. Cependant, la plupart des études expérimentales ont utilisé des doses de microsphères plastiques vierges qui sont plus ou moins représentatives d’une réalité environnementale encore mal connue et sans doute plus complexe. Un travail important reste à faire pour évaluer l’impact réel de la pollution des micro et nanoplastiques sur l’environnement marin. A l’occasion de cette présentation, nous verrons également comment les messages transmis par les médias au grand public, à partir des résultats d’études scientifiques sur la pollution plastique, sont parfois déformés et/ou simplifiés. Plus que jamais l’importance d’une information fiable et l’exercice du sens critique sont les clés de la compréhension du monde qui nous entoure et permettront aux citoyens que nous sommes d’agir en conséquence.

Orateur: Christophe Lambert (Laboratoire des Sciences de l’Environnement Marin)

17:30 → 18:00 No-coffee break

18:00 → 19:30 Beyond Standard Model

18:00 Introduction à la physique BSM

Orateur: Loic VALERY (DESY)

0-Loic-Intro.pdf

18:30 Recheche de particules se désintégrant en une paire de boson de Higgs dans le canal yybb à l'aide des données d'ATLAS

En 2012 les expériences ATLAS et CMS ont conjointement découvert le boson de Higgs, particule clé du Modèle Standard théoriquement prédite dans les années 1970. Depuis les études continuent afin de mesurer les différentes propriétés de ce boson, ce qui nous permettra de reconstruire le potentiel de Higgs et de tester le Modèle Standard. Une des propriétés qui pour le moment n'a pas été mesurée et dont le résultat pourrait avoir une influence sur la baryogenèse est le couplage trilinéaire (aussi appelé auto-couplage) du boson de Higgs, qui pourra être mesuré grâce à l'étude de la production de paires de bosons de Higgs. Cependant le taux de production est tellement faible qu'il ne pourra être observé qu'avec l'ensemble des données collectées d'ici la fin du programme du LHC en 2035. En revanche plusieurs théories au-delà du Modèle Standard prédisent l'existence de particules qui se désintégreraient en deux bosons de Higgs.
Parmi les différents canaux de désintégration, le canal dans lequel le premier boson de Higgs se désintègre en une paire de photons et le deuxième en une paire de quarks b est l'un des plus prometteurs car bénéficiant de la bonne résolution du premier et du grand rapport de branchement du second.
Je présenterai plus en détail l'analyse et les enjeux de cette recherche.

In 2012, the ATLAS and CMS experiments jointly discovered the Higgs boson, a key particle of the Standard Model of particle physics. This particle was predicted during the 70's. Since the discovery, studies has been carried on in order to measure the different properties of the Higgs boson. These measurements will help us to reconstruct the Higgs potential and test the Standard Model. One of the fundamental properties which has not been measured yet is the trilinear coupling (or self-coupling) of the Higgs boson. This coupling could lead to an explanation of the baryogenesis. However the cross section is so small that we do not expect it to be observed until the end of the LHC programme in 2035. But various theories beyond the Standard Model predict the existence of new particles that can decay in two Higgs bosons.
Among the different decay channels, the decay of the first Higgs boson into a pair of photons and the second Higgs boson into a pair of b-quark is the most promising one since it benefits from the good resolution on the photons for the first one and the high branching ratio of the second one.
During the presentation I will detail the analysis and the physics implications of this search.

Orateur: Raphaël Hulsken

JRJC_HULSKEN.pdf

19:00 Prospect for Lorentz invariance violation searches with top pair production at the LHC and future hadron colliders

In this talk, I will present a phenomenological study of Lorentz invariance violation with top pair production in proton-proton collision using sideral time. Opportunities at future hadron colliders (HL-LHC, HE-LHC, FCC) will also be discussed.

Orateur: Aurélien CARLE ({UNIV CLAUDE BERNARD}UMR5822)

Pres_JRJC_ACARLE.pdf

19:30 → 21:30 Diner

vendredi 29 novembre

08:30 → 10:00 Beyond Standard Model: Session I

Président de session: Loic VALERY (DESY)

08:30 Search for chargino and neutralino production in events with an isolated lepton, jets and missing transverse momentum at √s = 13 TeV with ATLAS detector

Orateur: Ngoc Khanh Vu

3-Khanh-EWSUSY.pdf

09:00 Search for additional neutral MSSM Higgs bosons decaying to tau lepton pairs in the CMS experiment at LHC

L'analyse des événements $H\to\tau\tau$ présente un intérêt certain pour l'étude du secteur du Higgs dans le cadre de l’extension supersymmétrique minimale du modèle standard. La sélection des événements d'intérêt répond à une logique basée sur la nature des particules impliquées, en particulier la paire de taus issus de la désintégration du Higgs. L'utilisation de régions de signal et de contrôle permet d'obtenir une estimation du bruit de fond et ainsi d'interpréter les données récoltées au LHC.

Enfin, les nombreuses sources d'incertitudes et la quantité d'évenements à traiter nécessitent une parallélisation des calculs afin de limiter leur durée d'exécution. Dans le cadre de l'utilisation de scripts python, l'utilisation du module dask permet une gestion des ressources optimisée.

Orateur: Lucas Torterotot (IP2I & CERN)

JRJC_Torterotot.pdf

09:30 Winding mode calculation of the effective potential in extra-dimensional theories

We propose a new method for calculating the effective potential in extra-dimensional theories, based on a resummation of the winding modes. This formalism is of particular interest for gauge-Higgs unification models for which the potential is entirely radiatively generated, but the method is of more general use. The winding modes formalism allows for a clean renormalisation procedure, a fast convergence of the sum on the modes, and also allows resumming of the result to all orders, guaranteeing to preserve the symmetries of the theory. We consider in detail the method and show a few illustrative examples of the calculations which are of interest for unification and for gauge-Higgs models.

Orateur: Corentin COT (IP2I)

JRJC_Talk (3).pdf

10:00 → 10:30 Coffee break

10:30 → 11:30 Beyond Standard Model: Session II

Président de session: Loic VALERY (DESY)

10:30 Search for resonances with inclusive Z boson events at large transverse momentum with ATLAS detector

This project presents a generic search for resonances in a model independent way using production of events with a Z boson with large transverse momentum (pT) recoiling against other final state X. The Z bosons decay leptonically to ee and μμ final states with Z pT > 100 GeV. The resonance hunted for could be either X or Y which decays Z+X

Orateur: Kunlin Han (LAL)

6-Kunlin-ZX.pdf

11:00 Search for new phenomena in low-mass diphoton final states with proton--proton collisions collected at s=√13 TeV with the ATLAS detector

The Higgs boson discovery by ATLAS and CMS collaborations relied mainly on resonance searches in two different channels, one of them being the diphoton channel. Since then, both experiments have extended the resonance search range towards lower and higher diphoton invariant masses up to limits driven by experimental limitations.

This talk focuses on a novel diphoton resonance search in the invariant mass range below 60 GeV using all Run2 data from pp collisions collected with the ATLAS detector at the Large Hadron Collider. Some perspectives on future analyses in the same mass region will be discussed.

Orateur: LUIS PASCUAL DOMINGUEZ (LPNHE)

third_draft_JRJC.pdf

11:45 → 17:45 Excursion

19:30 → 21:00 Diner

21:00 → 22:00 Closing session

21:00 Présentation de la SFP

ppt_SFP.pptx

21:30 Talk de conclusion

samedi 30 novembre

07:15 → 07:35 Depart navette