1,501 research outputs found
A ray mode parabolic equation for shallow water acoustics propagation problems
Ray mode parabolic equations which are suitable for shallow water acoustics
propagation problems are derived by the multiple-scale method.Comment: 7 pp., 0 fi
Optimal control over geomorphological systems
The method presented can be used for the planning of shore protection measures without seawalls or other cliff-protecting structures; it is particularly appropriate in cases where the system is eventually to control itself by adjustment to a dynamic equilibrium regim
LHCb trigger streams optimization
The LHCb experiment stores around collision events per year. A
typical physics analysis deals with a final sample of up to events.
Event preselection algorithms (lines) are used for data reduction. Since the
data are stored in a format that requires sequential access, the lines are
grouped into several output file streams, in order to increase the efficiency
of user analysis jobs that read these data. The scheme efficiency heavily
depends on the stream composition. By putting similar lines together and
balancing the stream sizes it is possible to reduce the overhead. We present a
method for finding an optimal stream composition. The method is applied to a
part of the LHCb data (Turbo stream) on the stage where it is prepared for user
physics analysis. This results in an expected improvement of 15% in the speed
of user analysis jobs, and will be applied on data to be recorded in 2017.Comment: Submitted to CHEP-2016 proceeding
Integrable relativistic systems given by Hamiltonians with momentum-spin-orbit coupling
In the paper we investigate the evolution of the relativistic particle
(massive and massless) with spin defined by Hamiltonian containing the terms
with momentum-spin-orbit coupling. We integrate the corresponding Hamiltonian
equations in quadratures and express their solutions in terms of elliptic
functions.Comment: 18 page
Probing Low Energy Neutrino Backgrounds with Neutrino Capture on Beta Decaying Nuclei
We study the interaction of low energy neutrinos on nuclei that spontaneously
undergo beta decay showing that the product of the cross section times neutrino
velocity takes values as high as 10^{-42} cm^2 c for some specific nuclei that
decay via allowed transitions. The absence of energy threshold and the value of
the cross section single out these processes as a promising though very
demanding approach for future experiments aimed at a direct detection of low
energy neutrino backgrounds such as the cosmological relic neutrinos.Comment: Includes a discussion of local relic neutrino density effect on
neutrino capture rate. Accepted for publication in JCA
Scattering of neutrinos on a polarized electron target as a test for new physics beyond the Standard Model
In this paper, we analyze the scattering of the neutrino beam on the
polarized electron target, and predict the effects of two theoretically
possible scenarios beyond the Standard Model. In both scenarios, Dirac
neutrinos are assumed to be massive.
First, we consider how the existence of CP violation phase between the
complex vector V and axial A couplings of the Left-handed neutrinos affects the
azimuthal dependence of the differential cross section. The future superbeam
and neutrino factory experiments will provide the unique opportunity for the
leptonic CP violation studies, if the large magnetized sampling calorimeters
with good event reconstruction capabilities are build.
Next, we take into account a scenario with the participation of the exotic
scalar S coupling of the Right-handed neutrinos in addition to the standard
vector V and axial A couplings of the Left-handed neutrinos. The main goal is
to show how the presence of the R-handed neutrinos, in the above process
changes the spectrum of recoil electrons in relation to the expected Standard
Model prediction, using the current limits on the non-standard couplings. The
interference terms between the standard and exotic couplings in the
differential cross section depend on the angle between the transverse
incoming neutrino polarization and the transverse electron polarization of the
target, and do not vanish in the limit of massless neutrino. The detection of
the dependence on this angle in the energy spectrum of recoil electrons would
be a signature of the presence of the R-handed neutrinos in the
neutrino-electron scattering. To make this test feasible, the polarized
artificial neutrino source needs to be identified.Comment: 11 pages, 3 eps figures, revtex, submitted to publicatio
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