Predictions on the Transverse Single-Spin Asymmetries at Subleading Twist of Pion Production in Semi-Inclusive DIS

2016 ◽  
Vol 40 ◽  
pp. 1660030
Author(s):  
Wenjuan Mao ◽  
Zhun Lu ◽  
Bo-Qiang Ma

We estimate the single-spin asymmetries with [Formula: see text] and [Formula: see text] angular dependencies for electroproduction of pions in transversely polarized semi-inclusive DIS process. We consider the effect of the twist-3 transverse momentum dependent distributions which convoluted with twist-2 fragmentation functions. We calculate these distributions in a spectator-diquark model, and predict the corresponding single-spin asymmetries at the kinematics of HERMES, JLab and COMPASS. We find that the numerical estimates show that the asymmetries are sizable, and the T-odd twist-3 TMDs play an important role in these asymmetries.

2014 ◽  
Vol 89 (11) ◽  
Author(s):  
M. Anselmino ◽  
M. Boglione ◽  
U. D’Alesio ◽  
S. Melis ◽  
F. Murgia ◽  
...  

2014 ◽  
Vol 25 ◽  
pp. 1460002 ◽  
Author(s):  
DENNIS SIVERS

This article presents a summary of overlapping presentations by the author to the QCD Evolution 2013 Workshop (Jefferson Lab, May 6-10, 2013) and to the Opportunities for Polarized Physics at Fermilab workshop (Fermilab, May 20-22, 2013). It contains an introduction to the concept of Kane-Pumplin-Repko (KPR) factorization and describes how this concept can be used in the analysis of high precision measurements of parity-conserving transverse single-spin asymmetries. The discussion demonstrates that such measurements can not only probe directly for specific mechanisms that enhance our fundamental understanding of nonperturbative QCD dynamics but, because transverse spin asymmetries are unambiguously parameterized by a spin-directed momentum shift, 〈δkTN (x, μ2)〉 such measurements can also be used to calibrate other phenomenological applications of transverse momentum dependent distributions (TMDs) and of TMD evolution. The calibration supplied by these measurements can thus enable the use of TMD factorization for the exploration of a broad range of other aspects of hadronic structure. KPR factorization ensures that 〈δkTN (x, μ2)〉 remains invariant under TMD evolution and this invariance can be used in the precision comparison of transverse single-spin asymmetries in the Drell-Yan process with those in Semi-inclusive deep inelastic scattering.


2016 ◽  
Vol 40 ◽  
pp. 1660045 ◽  
Author(s):  
Zhun Lu ◽  
Wenjuan Mao

The single-spin asymmetry [Formula: see text] of charged and neutral pion production in semi-inclusive deep-inelastic scattering on longitudinally polarized nucleon targets is studied. We particularly consider the effects of the twist-3 transverse-momentum dependent distribution functions [Formula: see text] and [Formula: see text], which are calculated in two different spectator-diquark models. We estimate the asymmetry for [Formula: see text], [Formula: see text] and [Formula: see text] produced off the proton target at HERMES and compare the results with the HERMES measurements. We also predict the same asymmetric moment for different pions at the kinematics of CLAS 5.5 GeV on a proton target, as well as at COMPASS on a deuteron target for comparison.


2015 ◽  
Vol 37 ◽  
pp. 1560033
Author(s):  
Daniel Pitonyak ◽  
Koichi Kanazawa ◽  
Yuji Koike ◽  
Andreas Metz

We provide a new analysis within collinear factorization of transverse single-spin asymmetries (TSSAs) in high transverse momentum charged and neutral pion production in pp collisions at the Relativistic Heavy Ion Collider (RHIC). This study incorporates the so-called twist-3 fragmentation term and shows that one can describe RHIC data through this mechanism. Moreover, by fixing other non-perturbative inputs through extractions of transverse momentum dependent functions in e+e- → h1h2X and semi-inclusive deep-inelastic scattering (SIDIS), we provide for the first time a consistency between certain spin/azimuthal asymmetries in all three reactions (i.e., pp, e+e-, and SIDIS).


2014 ◽  
Vol 25 ◽  
pp. 1460022 ◽  
Author(s):  
◽  
L. C. BLAND

We present first measurements of forward jet production from p↑ + p collisions at [Formula: see text] GeV, including transverse single spin asymmetries. These asymmetries are expected to be sensitive to spin-correlated transverse momentum in the initial state, which is particularly interesting because it is related to orbital angular momentum in the proton.


2019 ◽  
Vol 2019 ◽  
pp. 1-15 ◽  
Author(s):  
Hongxi Xing ◽  
Shinsuke Yoshida

The twist-3 collinear factorization framework has drawn much attention in recent decades as a successful approach in describing the data for single spin asymmetries (SSAs). Many SSAs data have been experimentally accumulated in a variety of energies since the first measurement was done in the late 1970s and it is expected that the future experiments like Electron-Ion-Collider will provide us with more data. In order to perform a consistent and precise description of the data taken in different kinematic regimes, the scale evolution of the collinear twist-3 functions and the perturbative higher-order hard part coefficients are mandatory. In this paper, we introduce the techniques for next-to-leading order (NLO) calculation of transverse-momentum-weighted SSAs, which can be served as a useful tool to derive the QCD evolution equation for twist-3 functions and to verify the QCD collinear factorization for twist-3 observables at NLO, as well as obtain the finite NLO hard part coefficients.


1999 ◽  
Vol 11 (4) ◽  
pp. 703-708 ◽  
Author(s):  
A. Ahmedov ◽  
I.V. Akushevich ◽  
E.A. Kuraev ◽  
P.G. Ratcliffe

Sign in / Sign up

Export Citation Format

Share Document