Hadron Physics 2030
The organisers of MDHS and JPhys++ projects, encouraged by the scientific council and the head
of Institut Pascal, have met in order to identify the possibility to merge the two events into a single one.
During this process it has been highlighted that, even if the objectives of the two events are distinct
and somehow not much overlapping, the JPhys project would strongly benefit of the outcome of some of the planned reflections and discussions expected to be hold during the MDHS project. Indeed, world experts in theory and phenomenology of the 3D hadron structure would join the MDHS program in order to answer the following question:
What are the best strategies to extract GPDs and TMDs from experimental data with a good control on theoretical systematic uncertainties?
The relevance of a future experimental program is strongly entangled with its ability to provide new sets of data able to strongly impact phenomenological studies, by smoothing sharp technical difficulties arising for instance from ill-posed inverse problems. Therefore, to ensure that these discussions take place and that the merging of the two previous projects becomes more than the sum of its parts, a reshuffling of the programs is presented here, spanning on three weeks.
The first week will mostly focus on the theory and simulation of hadron physics, and technical
discussions. During this period, topics which were expected to be mostly or exclusively covered in
MDHS will be treated, in parallel with the hadron spectroscopy component of JPhys++. The schedule
is expected to be rather dense, though the organisers will make sure that sufficient discussion time
will be allowed so that technical barriers can be lifted by small groups. A few key experimentalists
from JPhy++ will also join, in order to set the stage for the next two weeks, and insuring that first
interactions between theorists and experimentalists are set up.
The second week will be the real merged week, handing over smoothly the leadership from theorists
to experimentalists. We plan to organise summary talks of the first week, highlighting for the joining
experimentalists the outcomes of the theory discussions, in order to feed into their own strategy on
the design of future upgrades of the Jefferson Laboratory facility. In parallel to the experimental
discussion, we expect a continuing theory effort, especially regarding the study of Generalised Parton
Distributions and Transverse Momentum Dependent distributions. The presence of such theorists
through the second week will offer the possibility of joined discussion sessions.
The third week will be dedicated to the writing of the physics case of the future upgrades of
Jefferson Laboratory within a workshop mode organisation. This week will see a important use of
remote presentation tools, to ensure daily feedback from people located at Jefferson Laboratory.
Specific session will be dedicated to the writing of a scientific report, wrapping up the discussions held
at IPa.
We will also propose a public Lecture during each of the first two weeks, dedicated to the students
of th Université Paris-Saclay: one more oriented on the theoretical aspects of our physics domain, and
the another one on the experimental and technological challenges.
Cédric Mezrag (CEA), Éric Voutier (IJCLab- IN2P3) and partners from MDHS and JPhys++ programs
