Speaker
Description
TMD observables are normally expressed in terms of their contributions coming from different regions in transverse momentum. The low transverse momentum is often ascribed to an intrinsic non perturbative property of the hadron, described by TMD factorization, while the large transverse momentum region can be computed using fixed order collinear perturbation theory. In the middle region, often called the matching region, the two techniques fail to provide a satisfactory interpolation resulting in significant tension. The standard techniques used in high-energy physics don't carry over for moderate hard scales spoiling the hadronic structure interpretation. A recent approach, designed to retain this physical interpretation, significantly alleviates this tension by providing phenomenologists and model builders with a very general tool to incorporate both perturbative and non perturbative contributions in the parametrization of TMD densities while guaranteeing the matching in the large transverse momentum region.