A common library, TMDlib2, for Transverse-Momentum-Dependent distributions (TMDs) and unintegrated parton distributions (uPDFs) is described, which allows for easy access of commonly used TMDs and ...uPDFs, providing a three-dimensional (3D) picture of the partonic structure of hadrons. The tool TMDplotter allows for web-based plotting of distributions implemented in TMDlib2, together with collinear pdfs as available in LHAPDF.
The Parton Branching (PB) method describes the evolution of transverse momentum dependent (TMD) parton distributions, covering all kinematic regions from small to large transverse momenta
k
T
. The ...small
k
T
-region is very sensitive both to the contribution of the intrinsic motion of partons (intrinsic
k
T
) and to the resummation of soft gluons taken into account by the PB TMD evolution equations. We study the role of soft-gluon emissions in TMD as well as integrated parton distributions. We perform a detailed investigation of the PB TMD methodology at next-to-leading order (NLO) in Drell–Yan (DY) production for low transverse momenta. We present the extraction of the nonperturbative “intrinsic-
k
T
” distribution from recent measurements of DY transverse momentum distributions at the LHC across a wide range in DY masses, including a detailed treatment of statistical, correlated and uncorrelated uncertainties. We comment on the (in)dependence of intrinsic transverse momentum on DY mass and center-of-mass energy, and on the comparison with other approaches.
Abstract The Parton Branching (PB) method describes the evolution of transverse momentum dependent (TMD) parton distributions, covering all kinematic regions from small to large transverse momenta ...$$k_{\textrm{T}}$$ k T . The small $$k_{\textrm{T}}$$ k T -region is very sensitive both to the contribution of the intrinsic motion of partons (intrinsic $$k_{\textrm{T}}$$ k T ) and to the resummation of soft gluons taken into account by the PB TMD evolution equations. We study the role of soft-gluon emissions in TMD as well as integrated parton distributions. We perform a detailed investigation of the PB TMD methodology at next-to-leading order (NLO) in Drell–Yan (DY) production for low transverse momenta. We present the extraction of the nonperturbative “intrinsic- $$k_{\textrm{T}}$$ k T ” distribution from recent measurements of DY transverse momentum distributions at the LHC across a wide range in DY masses, including a detailed treatment of statistical, correlated and uncorrelated uncertainties. We comment on the (in)dependence of intrinsic transverse momentum on DY mass and center-of-mass energy, and on the comparison with other approaches.
Combined HERA data on charm production in deep-inelastic scattering have previously been used to determine the charm-quark running mass mc(mc) in the MS‾ renormalisation scheme. Here, the same data ...are used as a function of the photon virtuality Q2 to evaluate the charm-quark running mass at different scales to one-loop order, in the context of a next-to-leading order QCD analysis. The scale dependence of the mass is found to be consistent with QCD expectations.
The H1 very forward proton spectrometer at HERA Astvatsatourov, A.; Cerny, K.; Delvax, J. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2014, Letnik:
736
Journal Article
Recenzirano
The very forward proton spectrometer, VFPS, is a component of the H1 detector at the HERA collider. Scattered protons emitted with a polar angle less than 1mrad and carrying a fractional energy 1−xP, ...0.008<xP≤0.028 of the incident proton beam energy can be detected by scintillating fiber detectors which are read out by position sensitive photo-multipliers. These detectors are contained in Roman pot stations which are moved close to the circulating proton beam. The structure, operation and performance of the two Roman pot stations located at about 220m from the H1 interaction point in the cryogenic section of the proton ring are described.
A review is given of the measurements of the hard diffractive interactions in recent years from two high-energy colliders, the HERA
ep collider and the Tevatron
p
p
¯
collider. The structure of the ...diffractive exchange in terms of partons, the factorisation properties and the ratio of diffractive to non-diffractive cross sections are discussed.
Deeply virtual meson production on the nucleon Favart, L.; Guidal, M.; Horn, T. ...
The European physical journal. A, Hadrons and nuclei,
06/2016, Letnik:
52, Številka:
6
Journal Article
Recenzirano
Odprti dostop
.
We review the status of the data and phenomenology in the generalized parton distribution approach of deep virtual meson production.
We investigate the deeply virtual Compton scattering (DVCS) in the color dipole approach, implementing the dipole cross section through the saturation model, which interpolates successfully between ...soft and hard regimes. The imaginary and real part of the DVCS amplitude are obtained and the results are compared to the available data.
PDF
