35 research outputs found
High Power Cyclotrons for the Neutrino Experiments DAEÎŽALUS and IsoDAR
DAEÎŽALUS (Decay At rest Experiment for ÎŽcp At a Laboratory for Underground Science) has been proposed to measure the value of the CP violating phase delta through the oscillation of low energy muon anti-neutrinos to electron antineutrinos. With a single large detector, three accelerators at different distances enable the oscillation to be measured with sufficient accuracy. We have proposed the superconducting multi-megawatt DAEÎŽALUS Supercinducting Ring Cyclotron (DSRC) as the means of producing the 800 MeV 12 mA protons required, through the acceleration of H2+, ions with highly efficient stripping extraction. The DSRC comprises twin ion sources and injector cyclotrons, followed by a booster. The injector cyclotron can also be used for a separate experiment, IsoDAR (Isotope Decay At Rest) in which low energy protons produce Lithium 8, and thus a very pure electron antineutrino source which can be used to measure, or rule out, short range oscillation to a sterile neutrino. We describe recent developments in the designs of the injector and the booster, and the prospects for the two experiments
On the role of the magnetic dipolar interaction in cold and ultracold collisions: Numerical and analytical results for NH() + NH()
We present a detailed analysis of the role of the magnetic dipole-dipole
interaction in cold and ultracold collisions. We focus on collisions between
magnetically trapped NH molecules, but the theory is general for any two
paramagnetic species for which the electronic spin and its space-fixed
projection are (approximately) good quantum numbers. It is shown that dipolar
spin relaxation is directly associated with magnetic-dipole induced avoided
crossings that occur between different adiabatic potential curves. For a given
collision energy and magnetic field strength, the cross-section contributions
from different scattering channels depend strongly on whether or not the
corresponding avoided crossings are energetically accessible. We find that the
crossings become lower in energy as the magnetic field decreases, so that
higher partial-wave scattering becomes increasingly important \textit{below} a
certain magnetic field strength. In addition, we derive analytical
cross-section expressions for dipolar spin relaxation based on the Born
approximation and distorted-wave Born approximation. The validity regions of
these analytical expressions are determined by comparison with the NH + NH
cross sections obtained from full coupled-channel calculations. We find that
the Born approximation is accurate over a wide range of energies and field
strengths, but breaks down at high energies and high magnetic fields. The
analytical distorted-wave Born approximation gives more accurate results in the
case of s-wave scattering, but shows some significant discrepancies for the
higher partial-wave channels. We thus conclude that the Born approximation
gives generally more meaningful results than the distorted-wave Born
approximation at the collision energies and fields considered in this work.Comment: Accepted by Eur. Phys. J. D for publication in Special Issue on Cold
Quantum Matter - Achievements and Prospects (2011
Fatty acid profile and composition of milk protein fraction in dairy cows fed long-chain unsaturated fatty acids during the transition period
Analysis of fish assemblages in sectors along a salinity gradient based on species, families and functional groups
Mouse Chromosome 11
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46996/1/335_2004_Article_BF00648429.pd
Long-Baseline Neutrino Facility (LBNF) and Deep Underground Neutrino Experiment (DUNE) Conceptual Design Report Volume 2: The Physics Program for DUNE at LBNF
The Physics Program for the Deep Underground Neutrino Experiment (DUNE) at the Fermilab Long-Baseline Neutrino Facility (LBNF) is described
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PEP-II Assymetric B Factory: Design Update and R&D Results
Cost-effective Design Options for IsoDAR
This whitepaper reviews design options for the IsoDAR electron antineutrino source. IsoDAR is designed to produce electron antineutrinos per year with an average energy of 6.4 MeV, using isotope decay-at-rest. Aspects which must be balanced for cost-effectiveness include: overall cost; rate and energy distribution of the electron antineutrino flux and backgrounds; low technical risk; compactness; simplicity of underground construction and operation; reliability; value to future neutrino physics programs; and value to industry. We show that the baseline design outlined here is the most cost effectiv