Light vector meson production at forward rapidity in pp collisions at √s = 5.02 TeV with ALICE

Among the four fundamental forces, three of them occur at low scale. These three forces are all described in the so-called Standard Model of particles. Among them the force keeping the protons and neutrons bound together, the strong force, is of special interest in this presentation. This force is described by the Quantum Chromo-Dynamics (QCD) theory. Hadrons, such as protons and neutrons, are composed of gluons and quarks. Quarks are kept bound, at least by pairs by the strong force mediated via the gluons and cannot be dissociated. Only in the case of a high energy density (equivalent to high temperature) or at high baryon chemical potential, quarks and gluons can propagate freely, forming a Quark Gluon Plasma (QGP). This state is expected to have existed during the first micro- seconds of the Universe. These extreme conditions can actually be reproduced using heavy-ion collisions at the Large Hadron Collider (LHC). The QGP is expected to be created in the most central heavy ion collisions such as in Pb-Pb collisions at $\sqrt{s_{NN}}$ = 5.02~TeV. Used as a reference, pp collisions where the QGP is not expected to be created are also performed. The QGP can be studied, and its equation of state evaluated investigating the particle yields resulting from these collisions. Different probes of existence of the QGP are studied, in this thesis we investigate the low mass vector mesons with the dimuon decay channel at low mass ($m_{\mu\mu}<$2~GeV/$c^{2}$) measured in A Large Ion Collider Experiment (ALICE). Only interacting electroweakly within the medium, the dimuon decay channel is considered as a clean probe and allows the reconstruction of various mesons among which the $\omega$ and the $\phi$ meson. Due to its $s\bar{s}$ content, the $\phi$ meson has the particularity of having strange content, but a null net strangeness content. For this reason, the $\phi$ meson is a particular probe to study the so-called strangeness enhancement, an effect proposed as a signature of the QGP. However, the $\omega$ meson is composed of light flavour quarks and can be used as a reference for a strange hadron production. Recently observed in small collision systems (such as pp), the strangeness enhancement is benefiting of a regain of interest. In this thesis the results on the $\omega$ and $\phi$ mesons production in pp collision at $\sqrt{s}~=~$5.02~TeV at forward rapidity with ALICE is presented. This thesis present the production of these mesons as a function of their transverse momentum, rapidity and multiplicity and the comparison to various model predictions

Online Calibration of the TPC Drift Time in the ALICE High Level Trigger

ALICE (A Large Ion Collider Experiment) is one of four major experiments at the Large Hadron Collider (LHC) at CERN. The High Level Trigger (HLT) is a compute cluster, which reconstructs collisions as recorded by the ALICE detector in real-time. It employs a custom online data-transport framework to distribute data and workload among the compute nodes. ALICE employs subdetectors sensitive to environmental conditions such as pressure and temperature, e.g. the Time Projection Chamber (TPC). A precise reconstruction of particle trajectories requires the calibration of these detectors. Performing the calibration in real time in the HLT improves the online reconstructions and renders certain offline calibration steps obsolete speeding up offline physics analysis. For LHC Run 3, starting in 2020 when data reduction will rely on reconstructed data, online calibration becomes a necessity. Reconstructed particle trajectories build the basis for the calibration making a fast online-tracking mandatory. The main detectors used for this purpose are the TPC and ITS (Inner Tracking System). Reconstructing the trajectories in the TPC is the most compute-intense step. We present several improvements to the ALICE High Level Trigger developed to facilitate online calibration. The main new development for online calibration is a wrapper that can run ALICE offline analysis and calibration tasks inside the HLT. On top of that, we have added asynchronous processing capabilities to support long-running calibration tasks in the HLT framework, which runs event-synchronously otherwise. In order to improve the resiliency, an isolated process performs the asynchronous operations such that even a fatal error does not disturb data taking. We have complemented the original loop-free HLT chain with ZeroMQ data-transfer components. [...]Comment: 8 pages, 10 figures, proceedings to 2016 IEEE-NPSS Real Time Conferenc

Les perspectives des étudiants et des professeurs sur l’excellence dans l’utilisation des TIC et du cyberapprentissage au collégial

"Ce document est basé sur le rapport final d’un projet financé par le Fonds de recherche du Québec – Société et culture (FRQSC) et son partenaire, le ministère de l’Éducation et de l’Enseignement Supérieur (MEES) dans le cadre du programme Actions concertées Persévérance et réussite scolaires."Comprend un résumé, des références bibliographiques et des annexe

Student and professor perspectives on exemplary practices in the use of information and communication technologies (ICTs) and e-learning in colleges

"This document is based on the final report of a projet funded by the Fonds de recherche du Québec – Société et culture (FRQSC) and its partner the ministère de l’Éducation et de l’Enseignement supérieur (MEES) for the program Actions concertées Persévérance et réussite scolaires."Comprend un résumé, des références bibliographiques et des annexe

Culture shapes how we look at faces

Background: Face processing, amongst many basic visual skills, is thought to be invariant across all humans. From as early as 1965, studies of eye movements have consistently revealed a systematic triangular sequence of fixations over the eyes and the mouth, suggesting that faces elicit a universal, biologically-determined information extraction pattern. Methodology/Principal Findings: Here we monitored the eye movements of Western Caucasian and East Asian observers while they learned, recognized, and categorized by race Western Caucasian and East Asian faces. Western Caucasian observers reproduced a scattered triangular pattern of fixations for faces of both races and across tasks. Contrary to intuition, East Asian observers focused more on the central region of the face. Conclusions/Significance: These results demonstrate that face processing can no longer be considered as arising from a universal series of perceptual events. The strategy employed to extract visual information from faces differs across cultures

Les deux côtés de la médaille : la perception des élèves de l'usage que font leurs enseignantes et enseignants des technologies de l'information et de la communication (TIC)

Affiche présentée dans le cadre du Colloque de l'ARC, «La relève scientifique et la recherche collégiale : pratiques inspirantes au regard des chercheuses et chercheurs, et enjeux spécifiques à la formation des étudiantes et étudiants», dans le cadre du 84e Congrès de l'Acfas, Université du Québec à Montréal, Montréal, le 10 mai 2016.Le Réseau de recherche ADAPTECH a étudié la fréquence d’utilisation de divers outils technologiques en classe par des élèves de cégep, d’une part, et par des enseignantes et enseignants réputés auprès des élèves pour leur excellente utilisation de la technologie, d’autre part. Dans cette recherche, il s’est également demandé quels étaient les outils favorisant le mieux la réussite des élèves. Son objectif était d’examiner l’expérience des élèves avec les TIC au collégial, et de comprendre en quoi celle-ci se distingue de celle du personnel enseignant. Le terme TIC recouvrait une grande variété d’outils : tableaux blancs interactifs, télécommandes, système de gestion de cours, vidéoconférences, etc. L’étude explique comment on pourrait mieux utiliser les TIC en classe, car elle intègre les points de vue des élèves et ceux du personnel enseignant. Les similitudes et différences entre les deux groupes ont été analysées par un sondage en ligne auprès d’élèves (n = 311) et des entrevues semi-structurées auprès d’enseignantes et d’enseignants choisis par leurs élèves pour leur excellente utilisation des TIC (n = 114). Une des grandes différences est qu’un fort pourcentage des élèves aime les cours où ils utilisent leurs propres outils technologiques, alors qu’un faible pourcentage du personnel enseignant leur permet de le faire

Reading between Eye Saccades

Background: Skilled adult readers, in contrast to beginners, show no or little increase in reading latencies as a function of the number of letters in words up to seven letters. The information extraction strategy underlying such efficiency in word identification is still largely unknown, and methods that allow tracking of the letter information extraction through time between eye saccades are needed to fully address this question. Methodology/Principal Findings: The present study examined the use of letter information during reading, by means of the Bubbles technique. Ten participants each read 5,000 five-letter French words sampled in space-time within a 200 ms window. On the temporal dimension, our results show that two moments are especially important during the information extraction process. On the spatial dimension, we found a bias for the upper half of words. We also show for the first time that letter positions four, one, and three are particularly important for the identification of five-letter words. Conclusions/Significance: Our findings are consistent with either a partially parallel reading strategy or an optimal serial reading strategy. We show using computer simulations that this serial reading strategy predicts an absence of a wordlength effect for words from four- to seven letters in length. We believe that the Bubbles technique will play an importan

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems II: A 1 to 20 Micron Spectrum of the Planetary-Mass Companion VHS 1256-1257 b

We present the highest fidelity spectrum to date of a planetary-mass object. VHS 1256 b is a $<$20 M$_\mathrm{Jup}$ widely separated ($\sim$8\arcsec, a = 150 au), young, planetary-mass companion that shares photometric colors and spectroscopic features with the directly imaged exoplanets HR 8799 c, d, and e. As an L-to-T transition object, VHS 1256 b exists along the region of the color-magnitude diagram where substellar atmospheres transition from cloudy to clear. We observed VHS 1256~b with \textit{JWST}'s NIRSpec IFU and MIRI MRS modes for coverage from 1 $\mu$m to 20 $\mu$m at resolutions of $\sim$1,000 - 3,700. Water, methane, carbon monoxide, carbon dioxide, sodium, and potassium are observed in several portions of the \textit{JWST} spectrum based on comparisons from template brown dwarf spectra, molecular opacities, and atmospheric models. The spectral shape of VHS 1256 b is influenced by disequilibrium chemistry and clouds. We directly detect silicate clouds, the first such detection reported for a planetary-mass companion.Comment: Accepted ApJL Iterations of spectra reduced by the ERS team are hosted at this link: https://github.com/bemiles/JWST_VHS1256b_Reduction/tree/main/reduced_spectr

The JWST Early Release Science Program for Direct Observations of Exoplanetary Systems IV: NIRISS Aperture Masking Interferometry Performance and Lessons Learned

We present a performance analysis for the aperture masking interferometry (AMI) mode on board the James Webb Space Telescope Near Infrared Imager and Slitless Spectrograph (JWST/NIRISS). Thanks to self-calibrating observables, AMI accesses inner working angles down to and even within the classical diffraction limit. The scientific potential of this mode has recently been demonstrated by the Early Release Science (ERS) 1386 program with a deep search for close-in companions in the HIP 65426 exoplanetary system. As part of ERS 1386, we use the same dataset to explore the random, static, and calibration errors of NIRISS AMI observables. We compare the observed noise properties and achievable contrast to theoretical predictions. We explore possible sources of calibration errors, and show that differences in charge migration between the observations of HIP 65426 and point-spread function calibration stars can account for the achieved contrast curves. Lastly, we use self-calibration tests to demonstrate that with adequate calibration, NIRISS AMI can reach contrast levels of $\sim9-10$ mag. These tests lead us to observation planning recommendations and strongly motivate future studies aimed at producing sophisticated calibration strategies taking these systematic effects into account. This will unlock the unprecedented capabilities of JWST/NIRISS AMI, with sensitivity to significantly colder, lower mass exoplanets than ground-based setups at orbital separations inaccessible to JWST coronagraphy.Comment: 20 pages, 12 figures, submitted to AAS Journal