The international collaboration ALICE (“A Large Ion Collider Experiment”), of which the eponymous research group of the IP2I in Lyon is a member, aims to study nuclear matter in a state of extremely high temperature, where the deconfinement of hadrons (including protons and neutrons) into plasma of quarks and gluons takes place.
Matter is made up of atoms, themselves made up of electrons surrounding a nucleus of protons and neutrons, the latter being formed of quarks, linked by gluons. No quark or gluon has ever been observed in isolation: they appear to be permanently bonded together and confined in composite particles. At temperatures 100,000 times higher than those at the centre of the Sun, they deconform to form a plasma, which would have existed a few microseconds after the Big Bang. This plasma is predicted by the fundamental theory of strong interaction, Quantum Chromodynamics (QCD), and its study allows us to understand the ultimate organization of matter subject to strong interaction and the very first moments of the universe.
The LHC collides lead ions to recreate conditions similar to those immediately after the Big Bang and form this quark and gluon plasma. For this infinitely small study, a huge detector has been built at the LHC. It is capable of measuring the particles emitted by the plasma as it expands and cools.
Our group has been involved in this construction and in obtaining major results in this field of physics.
The activities of the ALICE group of the IP2I of Lyon are twofold:
- the analysis of data collected in proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN LHC
- participation in the construction and operation of the forward vertex trajectograph, the Muon Forward Tracker
Analysis of data collected in proton-proton, proton-nucleus and nucleus-nucleus collisions at the CERN LHC
The physics analyses of the ALICE experiment carried out in the Lyon groups cover a wide range of subjects, from the light quark sector u, d, s with the study of the forward production of low mass vector mesons and
in the dimuonic decay channel, to the heavy quarks sector c and b, with the study of the production of the quarkonium states of the
and
families. This analytical work has already led to a number of remarkable results, notably through the study of collective phenomena characterizing the evolution of the
and
mesons, namely the appearance of kinematic correlations between the
meson and light hadrons in high multiplicity proton-Pb collisions, and the observation of elliptical flow of the
meson compatible with zero in Pb-Pb collisions (behavior different from all the other particles studied).
Participation in the construction and operation of the forward vertex trajectograph, the Muon Forward Tracker
The group is also responsible for the construction and operation of the vertex forward trajectograph, the Muon Forward Tracker (MFT), one of the first applications in high energy physics of CMOS silicon pixel sensor technology. The MFT, which will be integrated into the ALICE detector starting with Run3 of the LHC (2021), is designed to enable precise measurement of the details of the vertex region for forward-produced particles, especially muons, whose different topologies and production processes can be studied.
NON-PERMANENTS:
- DOCTORANTS / DOCTORAL STUDENTS:
- K. Shchablo, I. Laktineh, M. Gouzevitch, C. Combaret, L. Mirabito. Performance of the CMS RPC upgrade using 2D fast timing readout system. 15th Vienna Conference on Instrumentation, Feb 2019, Vienna, Austria. pp.162139, ⟨10.1016/j.nima.2019.04.093⟩. ⟨hal-02507717⟩
- M.L. Gallin-Martel, L. Abbassi, J.-F. Adam, S. Brambilla, A. Bes, et al.. Diamond-based detector development for medical and nuclear applications. French Japanese Workshop on Diamond Power Devices, Jan 2019, Aussois, France. ⟨hal-02349542⟩
- Sukanya Pandeti, JoĂŁo Ameixa, Jusuf M. Khreis, Linda Feketeová, Fabien Chirot, et al.. Decomposition of protonated ronidazole studied by low-energy and high-energy collision-induced dissociation and density functional theory. The Journal of Chemical Physics, 2019, 151 (16), pp.164306. ⟨10.1063/1.5118844⟩. ⟨hal-02362185⟩
- Linda Feketeová, Paul Bertier, Thibaud Salbaing, Toshiyuki Azuma, Florent Calvo, et al.. Impact of a hydrophobic ion on the early stage of atmospheric aerosol formation. Proc.Nat.Acad.Sci., 2019, pp.201911136. ⟨10.1073/pnas.1911136116⟩. ⟨hal-02340285⟩
- F. Acernese, M. Agathos, L. Aiello, A. Allocca, A. Amato, et al.. Increasing the Astrophysical Reach of the Advanced Virgo Detector via the Application of Squeezed Vacuum States of Light. Physical Review Letters, 2019, 123 (23), pp.231108. ⟨10.1103/PhysRevLett.123.231108⟩. ⟨hal-02416888⟩
- Simone Ferraro, Michael J. Wilson, Muntazir Abidi, David Alonso, Behzad Ansarinejad, et al.. Astro2020 Science White Paper: Inflation and Dark Energy from Spectroscopy at
. Bull.Am.Astron.Soc., 2019, 51 (3), pp.72. ⟨hal-02116530⟩
- Jessica Garcia, David Barthelemy, Florence Geiguer, Julie Ballandier, Kathryn Li, et al.. Semi-automatic PD-L1 Characterization and Enumeration of Circulating Tumor Cells from Non-small Cell Lung Cancer Patients by Immunofluorescence. Journal of visualized experiments : JoVE, 2019, 150, pp.e59873. ⟨10.3791/59873⟩. ⟨hal-03133165⟩
- Veronica Tessaro, Floriane Poignant, Benoit Gervais, MichaĂ«l Beuve, Mariel E. Galassi. Theoretical study of W-values for particle impact on water. Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2019, 460, pp.259-265. ⟨10.1016/j.nimb.2018.11.031⟩. ⟨hal-01980804⟩
- Helene M. Courtois, Renee.C. Kraan-Korteweg, Alexandra Dupuy, Romain Graziani, Noam I. Libeskind. A kinematic confirmation of the hidden Vela supercluster. Monthly Notices of the Royal Astronomical Society, 2019, 490 (1), pp.L57-L61. ⟨10.1093/mnrasl/slz146⟩. ⟨hal-02327815⟩
- Mamadou Soumboundou, Innocent Nkengurutse, Julien Dossou, Bruno Colicchio, Catherine Djebou, et al.. Biological Dosimetry Network in Africa: Establishment of a Dose-response Curve Using Telomere and Centromere Staining. Health Physics, 2019, 117 (6), pp.618-624. ⟨10.1097/HP.0000000000001102⟩. ⟨hal-02309460⟩