During the first year of data taking ALICE has collected large data samples from pp collisions at the LHC (s=900 GeV and 7 TeV). They allowed us to have a first look at high-pT phenomena in a new ...energy regime. We give an overview of first results from the study of jet-like correlations and neutral meson production.
Abstract A study of prompt and non-prompt $$\mathrm {J}/\psi $$ J/ψ production as a function of charged-particle multiplicity in inelastic proton–proton (pp) collisions at a centre-of-mass energy of ...$$\sqrt{s}$$ s = 13 TeV based on calculations using the PYTHIA8 Monte Carlo is reported. Recent experimental data shows an intriguing stronger-than-linear increase of the self-normalized $$\mathrm {J}/\psi $$ J/ψ yield with multiplicity; several models, based on initial or final state effects, have been able to describe the observed behaviour. In this paper, the microscopic reasons for this behaviour, like the role of multiple parton interactions, colour reconnections and auto-correlations are investigated. It is observed that the stronger-than-linear increase and the transverse momentum ($$p_\mathrm {T}$$ pT ) dependence, contrary to what is predicted by the other available models, can be attributed to auto-correlation effects only. In absence of auto-correlation effects, the increase of the yield of $$\mathrm {J}/\psi $$ J/ψ with multiplicity – and in general for all hard processes – is weaker than linear for multiplicities exceeding about three times the mean multiplicity. The possibility of disentangling auto-correlation effects from other physical phenomena by measuring the charged-particle multiplicity in different pseudo-rapidity and azimuthal regions relative to the $$\mathrm {J}/\psi $$ J/ψ direction is investigated. In this regard, it is suggested to extend the experimental measurements of $$\mathrm {J}/\psi $$ J/ψ production as a function of the charged-particle multiplicity by determining the multiplicity in several azimuthal regions and in particular in the Transverse region with respect to the direction of the $$\mathrm {J}/\psi $$ J/ψ meson.
QCD challenges from pp to A–A collisions Adolfsson, J.; Andronic, A.; Bierlich, C. ...
The European physical journal. A, Hadrons and nuclei,
2020, Volume:
56, Issue:
11
Journal Article
Peer reviewed
Open access
This paper is a write-up of the ideas that were presented, developed and discussed at the third International Workshop on QCD Challenges from pp to A–A, which took place in August 2019 in Lund, ...Sweden (Workshop link:
https://indico.lucas.lu.se/event/1214/
). The goal of the workshop was to focus on some of the open questions in the field and try to come up with concrete suggestions for how to make progress on both the experimental and theoretical sides. The paper gives a brief introduction to each topic and then summarizes the primary results.
In central Pb-Pb collisions at the LHC at ' = 5.5 TeV, high rates are expected at energies at which jets can be reconstructed against the large background of the nucleus-nucleus underlying event. ...This will open the possibility to quantify the effect of partonic energy loss through medium induced gluon radiation (jet quenching) by detailed measurements of the modification of the longitudinal and transverse structure of identified jets. ALICE will use a combination of its central tracking system and the electromagnetic calorimeter (EMCal) to measure and trigger on jets. The projected performance of ALICE to perform these jet measurements will be discussed. The simulation results presented here have been also published in 1,2.
Student-generated video in chemistry education Gallardo-Williams, Maria; Morsch, Layne A; Paye, Ciana ...
Chemistry Education Research and Practice,
04/2020, Volume:
21, Issue:
2
Journal Article
Peer reviewed
Student-generated videos are growing in popularity in education generally, and in chemistry education there are several reports emerging on their use in practice. Interest in their use in chemistry ...is grounded in the visual nature of chemistry, the role of laboratory work in chemistry, and a desire to enhance digital literacy skills. In this perspective, we consider the place of student-generated videos in chemistry education, by first considering an appropriate pedagogical rationale for their usage. We then survey the reports of student-generated video with this framework in mind, exploring the role of generation in the reports surveyed. From this, we summarise the current status of student-generated videos in chemistry education and highlight from our readings some considerations for future research in this area, as well as guidelines for practitioners wishing to integrate student-generated video into their practice.
A study of prompt and non-prompt
J
/
ψ
production as a function of charged-particle multiplicity in inelastic proton–proton (pp) collisions at a centre-of-mass energy of
s
= 13 TeV based on ...calculations using the PYTHIA8 Monte Carlo is reported. Recent experimental data shows an intriguing stronger-than-linear increase of the self-normalized
J
/
ψ
yield with multiplicity; several models, based on initial or final state effects, have been able to describe the observed behaviour. In this paper, the microscopic reasons for this behaviour, like the role of multiple parton interactions, colour reconnections and auto-correlations are investigated. It is observed that the stronger-than-linear increase and the transverse momentum (
p
T
) dependence, contrary to what is predicted by the other available models, can be attributed to auto-correlation effects only. In absence of auto-correlation effects, the increase of the yield of
J
/
ψ
with multiplicity – and in general for all hard processes – is weaker than linear for multiplicities exceeding about three times the mean multiplicity. The possibility of disentangling auto-correlation effects from other physical phenomena by measuring the charged-particle multiplicity in different pseudo-rapidity and azimuthal regions relative to the
J
/
ψ
direction is investigated. In this regard, it is suggested to extend the experimental measurements of
J
/
ψ
production as a function of the charged-particle multiplicity by determining the multiplicity in several azimuthal regions and in particular in the Transverse region with respect to the direction of the
J
/
ψ
meson.
The ALICE dimuon spectrometer Morsch, A.
The European physical journal. C, Particles and fields,
07/2004, Volume:
34, Issue:
S1
Journal Article
Peer reviewed
Open access
AbstractThe ALICE forward muon spectrometer has been designed to measure the complete spectrum of heavy quark vector mesons via their muonic decays in pp, proton–nucleus (pA) and nucleus–nucleus ...(A–A) collisions. Here we present the main design criteria, an overview of the spectrometer and the status and plans of the project.
The ALICE Geant4 Simulation Hřivnáčová, I; Datskova, O; Gheata, A ...
Journal of physics. Conference series,
01/2011, Volume:
331, Issue:
3
Journal Article
Peer reviewed
Open access
ALICE adopted a strategy to develop a virtual interface to the detector simulation codes, the Virtual Monte Carlo 1, with which the transport of particles can be performed with three different ...detector simulation codes: GEANT 3.21 2, Geant4 3, and FLUKA 4. The Root geometrical modeller, TGeo 5, was adopted by ALICE as the unique geometry description in the simulation and reconstruction framework. This implied the integration of the TGeo geometrical modeller with all the transport codes used. GEANT3 was the most frequently used detector transport codes in past years, however, the recent LHC data production has created a greater interest in other transport codes. In this paper we will present our experience with Geant4. We will give an overview and the present status of the tools used in the Geant4 simulation: the implementation of the Virtual Monte Carlo interface, Geant4 VMC 6, and the implementation of Geant4 geometry navigation using directly the TGeo geometry, G4Root 7. We will also present the deployment of these tools on the Grid, the results obtained, as well as their comparison with GEANT3 and with real data.
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