Hadronization and fragmentation functions:

One of the crucial properties of the strong force is confinement, namely the fact that quarks and gluons (collectively named partons) cannot exist as free particles outside of hadrons. As a consequence, any individual parton struck in a high-energy scattering process and extracted from its parent hadron must transform (or, in technical language, hadronize) into at least one hadron. While hadronizing, the colored parton propagates through matter and binds itself through interactions in a massive and colorless hadron. Hadronization is thus tightly connected to the dynamical generation of the mass, the spin, and the size of hadrons, but the exact details of this transition are still unknown.

Hadronization and hadron structure are also very important in the context of high-energy physics, since sizeable uncertainties stem from our ignorance of the detailed structure of the hadronic initial and final states in hard scattering processes. These uncertainties can significantly hamper also searches for physics beyond the Standard Model (BSM). Fragmentation functions also act as a tool to study the inner spin and flavor structure of the nucleon and nuclei in highly energetic collisions, as envisioned at various experimental facilities (e.g. the 12 GeV upgrade at Jefferson Lab, RHIC, etc.), and at the future Electron-Ion Collider (EIC).

Goals of the workshop:

Understanding the hadronization mechanism is critically important to connect what happened between the hard interactions in a scattering process and the moment when the hadrons are observed in the detectors. Thus, fragmentation plays a substantial role in the ongoing physics programs at Jefferson Lab, RHIC, KEK, and will be essential at the EIC too. The preparation of the key measurements by a joint effort of the theoretical and experimental communities will crucially contribute to the preparation of the detector concepts and ensure the optimal scientific output of the EIC.

The workshop will be focused on experimental and theoretical aspects of the hadronization process, in particular on the fragmentation of quarks and gluons into single hadrons, hadron pairs and jets, together with their potential to access fundamental quantities in QCD. In the spirit of the “FF workshops” series, there will be room to address also new ideas and approaches within the community.