Exploring the Size of the Proton

This book is a rare jewel, describing fundamental research in a highly dynamic field of subatomic physics. It presents an overview of cross section measurements of deeply virtual Compton scattering. Understanding the structure of the proton is one of the most important challenges that physics faces today. A typical tool for experimentally accessing the internal structure of the proton is lepton–nucleon scattering. In particular, deeply virtual Compton scattering at large photon virtuality and small four-momentum transfer to the proton provides a tool for deriving a three-dimensional tomographic image of the proton. Using clear language, this book presents the highly complex procedure used to derive the momentum-dissected transverse size of the proton from a pioneering measurement taken at CERN. It describes in detail the foundations of the measurement and the data analysis, and includes exhaustive studies of potential systematic uncertainties, which could bias the result.

Jörg Philipp completed his diploma in physics in 2013 and his PhD in subatomic physics in 2017 at the Albert-Ludwigs-Universität Freiburg in Germany. In both cases he was deeply involved in the COMPASS II measurement program for exclusive reactions, which aims to improve our understanding of the nucleon by experimentally constraining  generalized parton distribution functions. Since 2017 he has worked as a PostDoc in subatomic physics and continues his research related to the measurement of exclusive and semi-inclusive reactions within the COMPASS collaboration. Since 2018 he has been affiliated to the Rheinische Friedrich-Wilhelms-Universität Bonn in Germany.