Accessing the nucleon transverse structure in inclusive deep inelastic scattering

Abstract

We revisit the standard analysis of inclusive Deep Inelastic Scattering off nucleons taking into account the fact that on-shell quarks cannot be present in the final state, but they rather decay into hadrons -a process that can be described in terms of suitable "jet" correlators. As a consequence, a spin-flip term associated with the invariant mass of the produced hadrons is generated nonperturbatively and couples to the target's transversity distribution function. In inclusive cross sections, this provides an hitherto neglected and large contribution to the twist-3 part of the g2 structure function, that can explain the discrepancy between recent calculations and fits of this quantity. It also provides an extension of the Burkhardt-Cottingham sum rule, providing new information on the transversity function, as well as an extension of the Efremov-Teryaev-Leader sum rule, suggesting a novel way to measure the tensor charge of the proton. II. THE QUARK-QUARK JET CORRELATORMotivated by mass corrections to inclusive DIS structure functions at large values of the Bjorken invariant x B , Accardi and Qiu [23] have introduced in the LO handbag diagram a "jet correlator", also called "jet factor" by

Transversity in inclusive DIS and novel TMD sum rules

“…For later use, we also define the average (chiral-odd) jet mass 6) or, in other words, the mass acquired by the quark interacting with vacuum fluctuations. In general, M q > m q , and for light quarks we estimate M q = O(100 MeV) [3].…”

“…The sum rule for E was introduced in Ref. [3], the others are new. Note that l 2 T ≡ ∑ h,S h dz d 2 P h⊥ (P 2 h⊥ /z 2 )D 1 (z, P h⊥ ) can be interpreted as the average squared transverse momentum of the quark in the hadron frame.…”

First extraction of transversity from data on lepton-hadron scattering and hadronic collisions

“…According to Ref. [20], the more stringent condition A q +a q > 1 is required to avoid a violation of the Burkardt-Cottingham sum rule by an infinite amount. Recently, Kovchegov and Sievert calculated the transversely polarized dipole scattering amplitude in the large-N c limit [21] (with N c the number of colors) and obtained that at very small x the transversity behaves as if A q + a q ≈ 1.…”

Quark fragmentation as a probe of dynamical mass generation

“…(9) The TMD inclusive jet correlator. It is useful to consider the cut quark propagator integrated over the plus component of the partonic momentum [14],…”

“…The sum rule (27) was first introduced in Ref. [14], but it is proven here for the first time in field theory. It generalizes the sum rule proposed in Ref.…”