Por Catarina Quintans (LIP)  

Abstract: The COMPASS experiment is presently taking data at CERN, to improve our knowledge of the strong interactions between quarks and gluons -- collectively called partons. These are the fundamental building blocks of massive matter in our universe. Quantum Chromodynamics, the theory of strong interactions, in spite of huge successes, is still unable to answer a number of fundamental questions: why is the proton stable, why its mass is so large, why it has spin=1/2? These are some of the topics we ultimately try to contribute to in COMPASS.

This unique fixed-target experiment made the first ever polarized Drell-Yan measurements in 2015, to help characterize the proton internal dynamics. Some of the newly released results will be described in a pedagogical way, giving hints for their possible impact in the field.