8,035 research outputs found
Exclusive processes with a leading neutron in collisions
In this paper we extend the color dipole formalism to the study of exclusive
processes associated with a leading neutron in collisions at high
energies. The exclusive , and production, as well as the
Deeply Virtual Compton Scattering, are analysed assuming a diffractive
interaction between the color dipole and the pion emitted by the incident
proton. We compare our predictions with the HERA data on production and
estimate the magnitude of the absorption corrections. We show that the color
dipole formalism is able to describe the current data. Finally, we present our
estimate for the exclusive cross sections which can be studied at HERA and in
future electron-proton colliders.Comment: 11 pages, 9 figures. Version published in Physical Review
Diffractive production at small in future Electron - Ion Colliders
The future Electron - Ion () Collider is expected to probe the high
energy regime of the QCD dynamics, with the exclusive vector meson production
cross section being one of the most promising observables. In this paper we
complement previous studies of exclusive processes presenting a comprehensive
analysis of diffractive production at small . We compute the coherent
and incoherent cross sections taking into account non-linear QCD dynamical
effects and considering different models for the dipole - proton scattering
amplitude and for the vector meson wave function. The dependence of these cross
sections with the energy, photon virtuality, nuclear mass number and squared
momentum transfer is analysed in detail. Moreover, we compare the non-linear
predictions with those obtained in the linear regime. Finally, we also estimate
the exclusive photon, and production and compare with the
results obtained for production. Our results demonstrate that the
analysis of diffractive production in future electron - ion colliders
will be important to understand the non-linear QCD dynamics.Comment: 12 pages, 8 figures, 1 table. Enlarged and revised version to be
published in the Journal of Physics G. arXiv admin note: text overlap with
arXiv:1503.0064
Investigating the impact of the gluon saturation effects on the momentum transfer distributions for the exclusive vector meson photoproduction in hadronic collisions
The exclusive vector meson production cross section is one of the most
promising observables to probe the high energy regime of the QCD dynamics. In
particular, the squared momentum transfer () distributions are an important
source of information about the spatial distribution of the gluons in the
hadron and about fluctuations of the color fields. In this paper we complement
previous studies on exclusive vector meson photoproduction in hadronic
collisions presenting a comprehensive analysis of the - spectrum measured
in exclusive , and photoproduction in and
collisions at the LHC. We compute the differential cross sections taking into
account gluon saturation effects and compare the predictions with those
obtained in the linear regime of the QCD dynamics. Our results show that gluon
saturation suppresses the magnitude of the cross sections and shifts the
position of the dips towards smaller values of .Comment: 7 pages, 5 figures. arXiv admin note: text overlap with
arXiv:1612.0625
Double vector meson production in the International Linear Collider
In this paper we study double vector meson production in
interactions at high energies and, using the color dipole picture, estimate the
main observables which can be probed at the International Linear Collider
(ILC). The total
cross-sections for , , and are computed
and the energy and virtuality dependencies are studied in detail. Our results
demonstrate that the experimental analysis of this process is feasible at the
ILC and it can be useful to constrain the QCD dynamics at high energies.Comment: 11 pages, 8 figure
Double vector meson production in interactions at hadronic colliders
In this paper we revisit the double vector meson production in interactions at heavy ion collisions and present, by the first time,
predictions for the and production in proton --
nucleus and proton -- proton collisions. In order to obtain realistic
predictions for rapidity distributions and total cross sections for the double
vector production in ultra peripheral hadronic collisions we take into account
of the description of cross section at low
energies as well as its behaviour at large energies, associated to the gluonic
interaction between the color dipoles. Our results demonstrate that the double
production is dominated by the low energy behaviour of the cross section. In contrast, for the double
production, the contribution associated to the description of the QCD dynamics
at high energies contributes significantly, mainly in collisions.
Predictions for the RHIC, LHC, FCC and CEPC - SPPC energies are shown.Comment: 9 pages, 5 figures, 2 tables. arXiv admin note: text overlap with
arXiv:1504.0441
A Framework for Dynamic Web Services Composition
Dynamic composition of web services is a promising approach and at the same time a challenging research area for the dissemination of service-oriented applications. It is widely recognised that service semantics is a key element for the dynamic composition of Web services, since it allows the unambiguous descriptions of a service's capabilities and parameters. This paper introduces a framework for performing dynamic service composition by exploiting the semantic matchmaking between service parameters (i.e., outputs and inputs) to enable their interconnection and interaction. The basic assumption of the framework is that matchmaking enables finding semantic compatibilities among independently defined service descriptions. We also developed a composition algorithm that follows a semantic graph-based approach, in which a graph represents service compositions and the nodes of this graph represent semantic connections between services. Moreover, functional and non-functional properties of services are considered, to enable the computation of relevant and most suitable service compositions for some service request. The suggested end-to-end functional level service composition framework is illustrated with a realistic application scenario from the IST SPICE project
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