A new extraction of the Boer-Mulders function

We extract the valence part of the nucleón Boer-Mulder (BM) function from the new COMPASS data on the unpolarized cosϕ h and cos 2 ϕ h asymmetries in SIDIS on deuteron for producing the hadron h and its antiparticle h ¯ at azimuthal angle ϕ h . Our results, obtained with only standard assumption of factorization of the x B ( z h ) and transverse momentum dependences, differ significantly from the presently published data on the BM function, obtained using a model assumption of proportionality to the better known Sivers function. This suggests that the published results on the BM function should be reconsidered.