We present a phenomenological extraction of transversity distribution
functions and Collins fragmentation functions by simultaneously fitting to
semi-inclusive deep inelastic scattering and electron-positron annihilation
data. The analysis is performed within the transverse momentum dependent
factorization formalism, and sea quark transversity distributions are taken
into account for the first time. We find the uˉ quark favors a negative
transversity distribution while that of the dˉ quark is consistent with
zero according to the current accuracy. In addition, based on a combined
analysis of world data and simulated data, we quantitatively demonstrate the
impact of the proposed Electron-ion Collider in China on precise determinations
of the transversity distributions, especially for sea quarks, and the Collins
fragmentation functions