We present a brief report on our ongoing efforts to calculate the transverse single-nucleon spin asymmetry of single-inclusive jet production in lepton-nucleon collisions at NLO accuracy within the collinear twist-3 factorization framework. This observable can very well be measured at a future Electron-Ion Collider (EIC). Such data will give new insight into both the partonic structure of the...
We present our results on transverse momentum dependent factorization and resummation at sub-leading power in Drell-Yan and semi-inclusive deep inelastic scattering. In these processes the sub-leading power contributions to the cross section enter as a kinematic power correction to the leptonic tensor, and the kinematic, intrinsic, and dynamic sub-leading contributions to the hadronic tensor....
We present results for the nucleon axial and pseudoscalar form factors extrapolated at the continuum limit using three $N_f = 2 + 1 + 1$ twisted mass fermion ensembles with all quark masses tuned to their physical values. Convergence to the ground state matrix elements is assessed using multi-state fits. We study the momentum dependence of the three form factors and check the partially...
In global extractions of Transverse momentum dependent (TMD) distributions, the limit of small transverse distances is constrained using the matching to collinear parton density functions (PDF). Naturally, the TMDPDFs depend on the baseline PDF set used certain features of the former might be due to the latter, rather than genuinely due to TMD behaviour f the partons. To shed light on the...
We review the current status of the nucleon's helicity PDFs. We describe
recent progress on "global" analysis of the distributions, highlighting
advances on the theoretical side especially in terms of higher-order
perturbative calculations. We discuss the relevance of these advances
for the spin program at the future EIC.
We present results for the axial, tensor, and scalar charges of the nucleon using lattice QCD simulations of twisted mass fermions with two degenerate light, a strange, and a charm quark, with masses tuned to their physical values (physical point simulations). The axial charge is well known experimentally and therefore provides for an important benchmark of our methodology, while the scalar...
The gravitational form factors (GFFs) of hadrons are related to the matrix elements of the energy-momentum tensor of QCD. In recent years, the proton and pion GFFs have been constrained for the first time from experimental measurements. We compute the quark and gluon GFFs of the pion and the nucleon in the kinematic region $0 < -t < 2~\text{GeV}^2$ on a clover improved lattice QCD ensemble...
The theory of the strong force, Quantum Chromodynamics, describes the proton in terms of quarks and gluons. The proton is a bound state of two up and one down quark, but quantum theory predicts that in addition there is an infinite number of quark-antiquark pairs. Both light and heavy quarks, whose mass is respectively smaller or bigger than the proton’s, are revealed inside the proton in...
In this contribution, I will present a recomputation of the evolution kernels of generalised parton distributions (GPDs) at one-loop accuracy for all of the three possible leading-twist polarisations: unpolarised, longitudinally polarised, and transversely/linearly polarised.
I will discuss the analytic and numerical properties of these kernels presenting a number of numerical results for...
We present the first direct lattice QCD calculation of the x-dependent pion distribution amplitudes on domain wall gauge ensembles at physical pion mass. We use the large momentum effective theory to directly calculate the x-dependence of meson DAs with several recently developed self-consistent precision control methods. We perform a leading renormalon resummation to remove linear...
In this presentation, we delve into the calculation of perturbative corrections for the Deeply Virtual Compton Scattering process within a unique kinematic domain, specifically where $t \gg \Lambda^2_{\rm QCD}$, with $t$ representing the change in nucleon momentum following scattering. Working within this unconventional domain necessitated a distinctive approach, particularly dealing with...
In this talk I present our work on the calculation of exclusive single jet and dijet production cross sections in polarized DIS. The NLO accuracy results are obtained with our extension of the dipole subtraction method to account for initial state polarized processes. In the case of single jet production, we also reach NNLO accuracy by applying the projection-to-Born (P2B) subtraction method....
Charged-current quasielastic neutrino scattering is the signal process in neutrino oscillation experiments and requires precise theoretical prediction for the analysis of modern and future experimental data, starting with the nucleon axial-vector form factor. In this talk, I compare a new MINERvA measurement of this form factor with lattice-QCD calculations and deuterium bubble-chamber data,...
A deeper understanding of the nucleon structure can be achieved through the study of Generalized Parton Distributions (GPDs).
The particularity of GPDs is that they convey an image of the nucleon structure where the longitudinal momentum and the
transverse spatial position of the partons inside the nucleon are correlated. Moreover, GPDs allow the quantification,
via Ji's sum rule, of the...
I will present some recent lattice QCD results on parton distribution functions, generalized parton distribution functions and distribution amplitudes. I will focus on results obtained using perturbative matching coefficients computed beyond the next-to-leading order in the strong coupling, specifically using next-to-next-to-leading order matching coefficients as well as incorporating various...
Generalized parton distributions (GPDs) are important quantities that characterize the 3-D structure of hadrons and complement the information extracted from TMDs. They provide information about the partons’ momentum distribution and also on their distribution in position space. The non-perturbative part of the cross-section of high-energy processes may be expanded in terms of the process's...
In this presentation we would like to determine the properties of the lightest resonance in
the baryonic sector of QCD: the Delta(1232) resonance. Using two-hadron operators we calculate the finite volume QCD energy spectrum of $\pi-N$ in the $p$-wave. Using Luescher formalism we can predict the mass and the width of the delta resonance. In our analysis we probe the Luescher formula by...
We investigate contributions of excited states to nucleon matrix elements by studying the two- and three-point functions using nucleon and pion-nucleon interpolating fields. This study is made using twisted mass fermion ensembles with pion masses 346 MeV and 131 MeV. We construct an improved nucleon interpolating field with the generalized eigenvalue problem of two-point functions, and use it...
