PoS(QCDEV2015)030 Constraints on the Collins Function from New e + e − → h 1 h 2 X Measurements in a Leading Order Analysis Mariaelena Boglione ∗ ab , Mauro Anselmino ab , Umberto D’Alesio cd , J.O. Gonzalez Hernandez ab , Stefano Melis a , Francesco Murgia d and Alexei Prokudin e a Dipartimento di Fisica, via Pietro Giuria 1, I-10125, Torino, Italy b INFN, Sezione di Torino, via Pietro Giuria 1, I-10125,Torino, Italy c Dipartimento di Fisica, Università di Cagliari, I-09042 Monserrato (CA), Italy d INFN, Sezione di Cagliari, C.P. 170, I-09042 Monserrato (CA), Italy e Division of Science, Penn State Berks, Reading, PA 19610, USA E-mail:boglione@to.infn.it, mauro.anselmino@to.infn.it, umberto.dalesio@ca.infn.it, joseosvaldo.gonzalez@to.infn.it, melis@to.infn.it, francesco.murgia@ca.infn.it, prokudin@jlab.org New data from the BaBar Collaborations, on azimuthal correlations measured for pairs of pions produced in e + e − annihilations, are analysed together with analogous, previous data from the BELLE Collaboration and with Semi-Inclusive Deep Inelastic scattering (SIDIS) data, for a si- multaneous extraction of transversity and the Collins function. Special attention is devoted to the p ⊥ dependence of the Collins favoured and disfavoured functions. A comparison with BESIII new measurements allows a preliminary study on the sensitivity of azimuthal asymmetries on TMD evolution effects. QCD Evolution 2015 -QCDEV2015- 26-30 May 2015 Jefferson Lab (JLAB), Newport News Virginia, USA ∗ Speaker. c  Copyright owned by the author(s) under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License (CC BY-NC-ND 4.0). http://pos.sissa.it/