4,136 research outputs found
Sorption properties of radiation-cross-linked polymer hydrogels containing ion-exchange fibers
Polymer hydrogel modification for soft contact lenses by ion-exchange fibers was studied in this work. The obtained results showed that the ion-exchange fiber modifiers have a number of advantages as compared with ion-exchange resin modifiers
Ultimate parameters of the photon collider at the ILC
At linear colliders, the e+e- luminosity is limited by beam-collision
effects, which determine the required emittances of beams in damping rings
(DRs). While in gamma-gamma collisions at the photon collider, these effects
are absent, and so smaller emittances are desirable. In present damping rings
designs, nominal DR parameters correspond to those required for e+e-
collisions. In this note, I would like to stress once again that as soon as we
plan the photon-collider mode of ILC operation, the damping-ring emittances are
dictated by the photon-collider requirements--namely, they should be as small
as possible. This can be achieved by adding more wigglers to the DRs; the
incremental cost is easily justified by a considerable potential improvement of
the gamma-gamma luminosity. No expert analysis exists as of yet, but it seems
realistic to obtain a factor five increase of the gamma-gamma luminosity
compared to the ``nominal'' DR design.Comment: Talk at LCWS06, Bangalore, India, March 2006, to be published in
Indian Journal of Physics, 5 pp, Latex, 1 .eps figur
The Study of Radiolysis of Ba(NO[3])[2] by ESR
Irradiation of Ba(NO[3])[2] [gamma]-rays at 308 K at increasing absorbed dose creates several new PC: 1, 2, 3, X. All of these are characterized by almost isotropic g-factor. Comparison of the observed parameters with literature data allows us to identify the PC as follows: 1 - O[3]{-}, 2 -O{-}. PC 3 and X presumably attributed to the complex centers [NO[2]...O[2]] or [NO[2]{-}...O{-}...O[2]]and [O{-}...O[2]], respectively
Heavy-to-heavy quark decays at NNLO
Details of a recent calculation of O(alpha_s^2) corrections to the decay b ->
c,l,nu_l, taking into account the c-quark mass, are described. Construction of
the expansion in the mass ratio m_c/m_b as well as the evaluation of new
four-loop master integrals are presented. The same techniques are applicable to
the muon decay, mu -> e,nu_mu,anti-nu_e. Analytical results are presented, for
the physical cases as well as for a model with purely-vector couplings.Comment: 11 page
Coulomb effects on growth of instabilities in asymmetric nuclear matter
We study the effects of the Coulomb interaction on the growth of unstable
modes in asymmetric nuclear matter. In order to compare with previous
calculations we use a semiclassical approach based on the linearized Vlasov
equation. Moreover, a quantum calculation is performed within the R.P.A.. The
Coulomb effects are a slowing down of the growth and the occurrence of a
minimal wave vector for the onset of the instabilities. The quantum corrections
cause a further decrease of the growth rates.Comment: 10 pages, revtex, 4 ps figures, to appear in Phys. Rev. C e-mail:
[email protected], [email protected]
Conformer of the peroxynitrite ion formed under photolysis of crystalline alkali nitrates – cis or trans?
The optical and infrared reflectance spectra of the crystalline powders prepared by co-crystallization of caesium nitrate, nitrite, and peroxynitrite from alkali solution have been studied. We find that the trans conformer forms under photolysis of crystalline pure caesium nitrate. Under its dissolution the trans conformer transforms to the cis conformer
Top-mass effects in differential Higgs production through gluon fusion at order \alpha_s^4
Effects from a finite top quark mass on differential distributions in the
Higgs+jet production cross section through gluon fusion are studied at
next-to-leading order in the strong coupling, i.e. . Terms
formally subleading in are calculated, and their influence on the
transverse momentum and rapidity distribution of the Higgs boson are evaluated.
We find that, for the differential K-factor, the heavy-top limit is valid at
the 2-3% level as long as the transverse momentum of the Higgs remains below
about 150 GeV.Comment: 21 pages, 12 figure
Finite top quark mass effects in NNLO Higgs boson production at LHC
We present next-to-next-to-leading order corrections to the inclusive
production of the Higgs bosons at the CERN Large Hadron Collider (LHC)
including finite top quark mass effects. Expanding our analytic results for the
partonic cross section around the soft limit we find agreement with a very
recent publication by Harlander and Ozeren \cite{Harlander:2009mq}.Comment: 15 page
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