COMPASS collaboration (199 authors)Bordalo, P.Franco, C.Nunes, A.S.Quaresma, M.Quintans, C.Ramos, S.Silva, L.Stolarski, M.2019-02-032019-02-032012-06-18http://dx.doi.org/10.1016/j.physletb.2012.05.015http://hdl.handle.net/10400.26/26113First 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 2007 with the COMPASS spectrometer using a muon beam of 160 GeV/c at the CERN SPS. The asymmetries provide access to the transversity distribution functions, without involving the Collins effect as in single hadron production. The sizeable asymmetries measured on the NH_ target indicate non-vanishing u-quark transversity and two-hadron interference fragmentation functions. The small asymmetries measured on the ^6LiD target can be interpreted as indication for a cancellation of u- and d-quark transversities.engjournal article2019-02-03