Abstract
Unpolarised semi-inclusive DIS is receiving a growing interest as a powerful tool to access poorly known universal functions that play a key role in many processes, in particular in the study of the spin structure of the nucleon. These functions can be investigated through experimental observables such as hadron multiplicities in the collinear and transverse framework, the dihadron multiplicities, the azimuthal asymmetries and some others. New results on these observables by the COMPASS experiment at CERN will be shown and discussed.
Highlights
Over the last few decades, a major effort has been dedicated, both on experimental and theoretical sides, to the study of the nucleon spin structure by determining the parton helicity and transversity distributions, considering that the internal 2−D partonic structure of the nucleon is precisely known except the strange quark density which still carries a large uncertainty
A considerable effort is being dedicated to achieve a good level of understanding of the internal 3−D partonic structure of the nucleon
In addition to the many advantages that SIDIS offers as flavour and charge separation, its relevance for spin physics and its accessibility to large hadron energy fraction, it covers a wide range in the energy scale allowing to improve the scale coverage in the Q2 evolution, essential to determine gluon contribution
Summary
Over the last few decades, a major effort has been dedicated, both on experimental and theoretical sides, to the study of the nucleon spin structure by determining the parton helicity and transversity distributions, considering that the internal 2−D partonic structure of the nucleon is precisely known except the strange quark density which still carries a large uncertainty. A considerable effort is being dedicated to achieve a good level of understanding of the internal 3−D partonic structure of the nucleon. We present recent measurements of experimental observables which encode details of the transverse momentum effects in SIDIS, using data samples collected by the COMPASS collaboration at CERN. Among these observables are the p2T -dependent multiplicities and the azimuthal asymmetries of unidentified hadrons, both measured in unpolarised semi-inclusive DIS. In sec. 2, the experimental setup is briefly described, the hadrons multiplicities (analysis and results) are presented in sec. 3 and the azimuthal asymmetries are presented in sec. 5
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
