6,541 research outputs found
Diffractive vector meson production at large- in coherent hadronic interactions at CERN LHC
The diffractive vector meson photoproduction with hadron dissociation in
coherent hadron-hadron interactions at LHC energies is studied assuming that
the color singlet -channel exchange carries large momentum transfer. We
estimate the rapidity distribution and total cross section for the processes
and ( or )
considering the non-forward solution of the BFKL equation at high energy and
large momentum transfer. Our results indicate that the experimental
identification of these processes can be feasible at the LHC.Comment: 11 pages, 3 figures, 1 table. Version to be published in European
Physical Journal
Probing the BFKL dynamics in the Vector Meson Photoproduction at large -- in collisions at the CERN LHC
The photoproduction of vector mesons in collisions at LHC energies is
investigated assuming that the color singlet -channel exchange carries a
large momentum transfer . The rapidity distributions and total cross
sections for the process ,
with and representing a rapidity gap in the
final state, are estimated considering the non-forward solution of the BFKL
equation at high energy and large -- . A comparison with the predictions
obtained at the Born level also is presented. We predict a large enhancement of
the cross sections associated to the BFKL dynamics in the kinematical range
probed by the LHCb Collaboration. Moreover, our results indicate that the
experimental identification can be feasible at the LHC and that this process
can be used to probe the BFKL dynamics.Comment: 7 pages, 4 figures, 1 table. Improved version to be published in
Physics Letters B. arXiv admin note: text overlap with arXiv:0911.563
Probing the gluon density of the proton in the exclusive photoproduction of vector mesons at the LHC: A phenomenological analysis
The current uncertainty on the gluon density extracted from the global parton
analysis is large in the kinematical range of small values of the Bjorken -
variable and low values of the hard scale . An alternative to reduces this
uncertainty is the analysis of the exclusive vector meson photoproduction in
photon - hadron and hadron - hadron collisions. This process offers a unique
opportunity to constrain the gluon density of the proton, since its cross
section is proportional to the gluon density squared. In this paper we consider
current parametrizations for the gluon distribution and estimate the exclusive
vector meson photoproduction cross section at HERA and LHC using the leading
logarithmic formalism. We perform a fit of the normalization of the
cross section and the value of the hard scale for the process and demonstrate
that the current LHCb experimental data are better described by models that
assume a slow increasing of the gluon distribution at small - and low
.Comment: 8 pages, 6 figures, 1 table. Version published in European Physical
Journal
Meson production in two-photon interactions at energies available at CERN Large Hadron Collider
The meson production cross sections are estimated considering photon-photon
interactions in hadron - hadron collisions at CERN LHC energies. We consider a
large number of mesons with photon-photon partial decay width well constrained
by the experiment and some mesons which are currently considered as hadronic
molecule and glueball candidates. Our results demonstrate that the experimental
analysis of these states is feasible at CERN - LHC.Comment: 5 pages, 1 figure, 4 tables. Version published in Physical Review
Properties improvement of poly(o-methoxyaniline) based supercapacitors : experimental and theoretical behaviour study of self-doping effect
The support of this research by FAPESP (2011/10897-2, 2013/07296-2), CsF-PVE (99999.007708/2015-07), CAPES and CNPq is gratefully acknowledged. We also thank the University of Aberdeen for providing computational time on MaxwellPeer reviewedPostprin
Monitoring techniques for the manufacture of tapered optical fibers
The use of a range of optical techniques to monitor the process of fabricating optical fiber tapers is investigated. Thermal imaging was used to optimize the alignment of the optical system; the transmission spectrum of the fiber was monitored to confirm that the tapers had the required optical properties and the strain induced in the fiber during tapering was monitored using in-line optical fiber Bragg gratings. Tapers were fabricated with diameters down to 5 μm and with waist lengths of 20 mm using single-mode SMF-28 fiber
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