Spin asymmetries in electron-jet production at the future electron ion collider

Abstract

We study all the possible spin asymmetries that can arise in back-to-back electron-jet production, ep → e + jet + X, as well as the associated jet fragmentation process, ep → e+jet(h)+X, in electron-proton collisions. We derive the factorization formalism for these spin asymmetries and perform the corresponding phenomenology for the kinematics relevant to the future electron ion collider. In the case of unpolarized electron-proton scattering, we also give predictions for azimuthal asymmetries for the HERA experiment. This demonstrates that electron-jet production is an outstanding process for probing unpolarized and polarized transverse momentum dependent parton distribution functions and fragmentation functions.

Longitudinal and transverse polarizations of $Λ$ hyperon in unpolarized SIDIS and $e^+e^-$ annihilation

“…Inserting Eqs. (31) and (32) into Eq. ( 30), carrying out traces, and making Lorentz contractions with the leptonic tensor, we obtain expressions of the structure functions at the leading twist.…”

“…and ΞΛ q (z Λ , p T ) has exactly the same form as Eq. (32). A sum over quark flavors and an exchange between q and q are also implicit.…”

“…Recently, Belle collaboration has measured the transverse polarization of Λ hyperons produced in e + e − annihilation [26] and has inspired immediate parameterizations [27][28][29] and model calculations [30] of the D ⊥Λ 1T q (z Λ , p T ). Efforts have also been made towards predicting the transverse polarization of Λ hyperon in SIDIS [31][32][33][34]. We note in particular that the parameterization in [29] emphasizes on the isospin symmetry while those in [27,28] include quite significant isospin symmetry violations.…”

Transverse Lambda production at the future Electron-Ion Collider

“…Furthermore, in Refs. [34][35][36] the authors discuss that by measuring the distribution of hadrons relative to the jet axis, one de-correlates the TMD FF in the TMD fragmenting jet function and the other TMDs in the process. As a result, in Ref.…”

“…As a result, in Ref. [36,37], it was proposed to measure the distribution of hadrons in a jet in back-to-back electron-jet production as a probe of TMD FFs.…”