Related papers: Transverse spin azimuthal asymmetries in SIDIS at …
The COMPASS experiment at the CERN SPS investigates the structure and spectrum of hadrons by scattering high energetic hadrons and polarised muons off various fixed targets. During the years 2002-2007, COMPASS focused on nucleon spin…
We investigate the transverse momentum weighted Sivers asymmetries in the processes with transversely polarized proton target, including the $\frac{P_{hT}}{zM_p}\sin (\phi_h-\phi_S)$ weighted asymmetry in charged hadron production in…
The azimuthal angle ($\phi_h$) distribution of hadrons produced in deep inelastic scattering serves as a powerful tool for probing the nucleon structure in terms of transverse momentum dependent parton distribution functions and…
The COMPASS Collaboration is measuring the asymmetries in the azimuthal distributions of positive and negative hadrons produced in Deep Inelastic Scattering (DIS) on unpolarized protons. The data have been collected in 2016 and 2017 with a…
Azimuthal Asymmetries in unpolarized SIDIS can be used to probe the transverse momentum of quarks inside the nucleon. Furthermore, they give access to the so-far unmeasured Boer-Mulders function. We report on the first measurement of…
Measuring single spin asymmetries in semi-inclusive deep-inelastic scattering (SIDIS) on a transversely polarized target gives a handle to investigate the transversity distribution and transverse momentum dependent distribution functions.…
In order to illustrate the capabilities of COMPASS using a hadronic beam, I review some of the azimuthal asymmetries in hadronic collisions, that allow for the extraction of transversity, Sivers and Boer-Mulders functions, necessary to…
In semi-inclusive DIS of polarized leptons on a transversely polarized target eight azimuthal modulations appear in the cross-section. Within QCD parton model four azimuthal asymmetries can be interpreted at leading order, two of them being…
Large transverse single spin asymmetries (SSA) were measured for pions produced in pp-collisions up to RHIC energies. Sizeable SSA were also found in semi-inclusive deep inelastic scattering (SIDIS). Theory can explain such spin effects by…
New results on single spin asymmetries of identified charged pion and kaon pairs produced in deep-inelastic scattering of muons on a transversely polarized 6LiD target are presented. The data were taken in the years 2003 and 2004 with the…
One of the main aims of the COMPASS experiment at CERN is the study of the spin structure of the nucleon and in particular the determination of the gluon polarization in the nucleon. We present some new results of 2002-2003 data analysis.…
In this review a first comprehensive study of azimuthal asymmetries in semi-inclusive deep inelastic muoproduction of hadron pairs off longitudinally polarized protons at COMPASS is presented. The study is based on data taken in 2007 and…
In a previous publication [Beni\' c et al., Phys. Rev. D104 (2021) 094027], we have computed the perturbative QCD contribution to transverse single spin asymmetries (SSAs) in semi-inclusive Deep Inelastic Scattering (SIDIS) involving the…
We perform global fit to the quark Sivers function within the transverse momentum dependent (TMD) factorization formalism in QCD. We simultaneously fit Sivers asymmetry data from Semi-Inclusive Deep Inelastic Scattering (SIDIS) at COMPASS,…
In 2022, the COMPASS collaboration performed semi-inclusive measurements of deep-inelastic muon-scattering on a transversely polarised deuteron (6LiD) target. From these data, transverse-spin-dependent dihadron asymmetries are extracted…
We investigate the energy evolution of the azimuthal spin asymmetries in semi-inclusive hadron production in deep inelastic scattering (SIDIS) and Drell-Yan lepton pair production in pp collisions. The scale dependence is evaluated by…
First measurements of azimuthal asymmetries in hadron-pair production in deep-inelastic scattering of muons on transversely polarised ^6LiD (deuteron) and NH_3 (proton) targets are presented. The data were taken in the years 2002-2004 and…
The inclusive A_1,p and hadron double-spin asymmetries A_p^pi+, A_p^pi-, A_p^K+, A_p^K- measured at COMPASS (CERN SPS) in deep-inelastic scattering of a polarized muon beam off a polarized NH_3 solid target are presented. The results have…
In 2016 and 2017 COMPASS has collected a considerable amount of deep inelastic scattering events with a 160 GeV/c muon beam and a liquid hydrogen target. An analysis of 4 % of these data has allowed to extract preliminary results on the…
We study single-spin asymmetries in semi-inclusive deep inelastic scattering with transversely polarized target. Based on the QCD factorization approach, we consider Sivers and Collins contributions to the asymmetries. We fit simple…