Gluodynamics

The Gluodynamics project: probing the nature of dense gluonic systems

 

The project P2IO Gluodynamics will allow to investigate gluons as source of geometry of protons and nuclei and source of force inside strongly interacting matter thanks to modern hadron structure and fluid dynamic descriptions of hadronic interactions and their interconnections.

 

CONTEXT:

The strong interaction, mediated by gluons, is responsible for most of the mass of ordinary matter according to simulations on the lattice, whereas the Englert-Brout-Higgs mechanism (Nobel prize 2013) accounts only for a small fraction of it. The gluonic structure of strongly interacting particles, hadrons, is indeed key for the understanding of the properties of the universe. However, the gluonic sector of hadrons remains largely unexplored at present. Furthermore, strongly interacting thermodynamic systems at high temperatures are governed by fluid dynamics where a description in terms of ordinary hadronic matter becomes inapplicable. At these temperatures, a phase called Quark-Gluon Plasma is produced whose internal structure in terms of its degrees of freedom and the interactions between the latter remain largely unknown.

Several theoretical concepts, largely developed in the laboratories of P2IO, allow for a rigorous study of hadron structure. They either access the structure in coordinate space, transverse momentum space or investigate the properties of hadrons in the limit of very large collision energies. However, the gluonic distributions in coordinate and momentum space are largely unknown since gluons do not interact electromagnetically and information has to be inferred indirectly. The gluon dominated initial-state density and its geometry is one of the main ingredients to describe the strongly interacting fluid created in the laboratory.

The knowledge of these initial conditions will profit from insights gained in studies of hadron structure and is a prerequisite for precision studies of QCD matter properties. Furthermore, experimental opportunities open up at the LHC to constrain hadron structure.

PROJECT:

A systematic study of dense strongly interacting systems, hadrons, and fluid-dynamic systems exploiting modern concepts, new experiments, and their connections will be realized through 4 work streams:

1. Geometry: the experimental and theoritical study of nucleon and nuclear geometry in electron-hadron reactions at JLab (electron-hadron) and photon-hadron collisions at the LHC
2. Unification: the unificationof different theoretical frameworks for the study of hadrons and ab-initio QCD calculations and hydrodynamics as well as the promotion of software tools being developed within P2IO
3. Gluometer: the experimental investigation of the gluonic force via gluometers at the LHC with quarkonium as forcemeter in collider in fixed-target mode and in jets to learn about gluon radiation: the current understanding is limited to a large extent to qualitative insights that can be extended to a deeper understanding by new and more precise observations
4. Future: lay the ground for future experimental QCD collider programs in the post 2030 era with dedicated detector simulation studies for future collider facilities as the Electron-ion Collider as well as detector upgrades of LHCb at the LHC: the exploitation of data recorded at future facilities (EIC, LHC) will require optimizations of the detector, read-out and reconstruction chain designs.

EXPECTED IMPACTS:

This unique synergetic scientific program will allow improving our understanding of the underlying mechanisms of strong interaction and the smallest fluids on earth. Furthermore, it will prepare the local community to the upcoming experimental and theoretical challenges at the EIC and the HL-LHC. The project will have a high scientific impact on international level thanks to the unique P2IO landscape with its combination of word-leading theoretical and experimental experts of hadrons and heavy-ions physics.

Precisely, this interchange between theory, phenomenology, experimental analysis, and simulation studies for the future is required to progress in the quest for the nucleon structure and the Quark-Gluon Plasma, i.e., probing QCD in its extremes. The combination of hadrons structure and heavy-ion expertise on the experimental and theoretical side is innovative. 

 

P2IO LABORATORIES INVOLVED IN THE PROJECT:

CEA IRFU: DPhN;

CEA IPHT;

IJCLab;

LLR, CPHT

 

PROJECT SPOKESPEOPLE:

Michael Winn ( ) and Cyrille Marquet ( )

 

To go further: http://www.p2io-labex.fr/en/Phocea/Page/index.php?id=27