1,373 research outputs found
Physics reach of -beams and -factories: the problem of degeneracies
We discuss the physics reach of -Beams and -Factories from a
theoretical perspective, having as a guideline the problem of degeneracies. The
presence of degenerate solutions in the measure of the neutrino oscillation
parameters and is, in fact, the main problem that have
to be addressed in planning future neutrino oscillation experiments. If
degeneracies are not (at least partially) solved, it will be almost impossible
to perform, at any future facility, precise measurements of
and/or . After a pedagogical introduction on why degenerate solutions
arise and how we can get rid of them, we analyze the physics reach of current
-beam and -factory configurations. The physics reach of the
"standard" \BB is severely affected by degeneracies while a better result can
be obtained by higher- setups. At the \NF the combination of Golden and
Silver channels can solve the eightfold degeneracy down to Comment: 5 pages, 6 epsfig; NUFACT'05, 21-26 June 2005, Frascat
The functionalization of carbon nanotubes using a batch oscillatory flow reactor
This paper describes an efficient method for the functionalizing of multi-walled carbon nanotubes (MWCNT) using oscillatory flow mixing (OFM). A 3. l batch oscillatory flow reactor (OFR) was designed and constructed for pilot scale functionalization of MWCNT in order to potentially improve their compatibility within a thermoplastic polyphenylene sulphide (PPS) matrix. The OFM batch reactor consisted of a jacketed cylindrical vessel with a vertical axial oscillator that contained a series of baffled mixing plates. MWCNTs dispersed in dimethylformamide (DMF) were introduced into the reactor and a two stage reaction for functionalizing MWCNTs with PPS compatible groups was carried out under oscillation of baffles at elevated temperatures. Fluid mixing observations in the reactor showed that MWCNTs formed a uniform dispersion of aggregated flocs before and during the functionalization reaction. On completion of the reaction and cessation of the oscillation, the aggregated flocs of MWCNT rapidly sedimented at the bottom of the reactor; hence could be collected as a concentrated mass thereby facilitating the separation of functionalized MWCNTs from the solvent. The functionalized MWCNTs were dried and then characterized by transmission electron microscopy, infrared spectroscopy as well as thermal gravimetric analysis in order to investigate the extent of MWCNT functionalization. The characterization results confirmed the effective and relatively uniform functionalization of the MWCNTs despite formation of aggregates, indicating that OFM provides a viable approach for functionalizing MWCNTs
Untangling CP Violation and the Mass Hierarchy in Long Baseline Experiments
In the overlap region, for the normal and inverted hierarchies, of the
neutrino-antineutrino bi-probability space for appearance,
we derive a simple identity between the solutions in the (, ) plane for the different hierarchies. The
parameter sets the scale of the
appearance probabilities at the atmospheric eV whereas controls the amount of CP
violation in the lepton sector. The identity between the solutions is that the
difference in the values of for the two hierarchies equals twice
the value of divided by the {\it critical} value
of . We apply this identity to the two proposed
long baseline experiments, T2K and NOA, and we show how it can be used to
provide a simple understanding of when and why fake solutions are excluded when
two or more experiments are combined. The identity demonstrates the true
complimentarity of T2K and NOA.Comment: 15 pages, Latex, 4 postscript figures. Submitted to New Journal of
Physics, ``Focus on Neutrino Physics'' issu
Degeneracies at a beta-Beam and a Super-Beam Facility
The presence of degeneracies can considerably worsen the measure of the
neutrino oscillation parameters and . We study the
physics reach of a specific ``CERN'' setup, using a standard -Beam and
Super-Beam facility. These facilities have a similar sensitivity in both
parameters. Their combination does not provide any dramatic improvement as
expected due to their almost identical L/E ratio. We analyse if adding the
correspondent disappearance channels can help in reducing the effect of
degeneracies in the measure.Comment: 5 pages, 7 eps figure
Study of the eightfold degeneracy with a standard -Beam and a Super-Beam facility
The study of the eightfold degeneracy at a neutrino complex that includes a
standard -Beam and a Super-Beam facility is presented for the first time
in this paper. The scenario where the neutrinos are sent toward a Megaton water
Cerenkov detector located at the Fr\'{e}jus laboratory (baseline 130 Km) is
exploited. The performance in terms of sensitivity for measuring the continuous
( and ) and discrete ( and
) oscillation parameters for the -Beam
and Super-Beam alone, and for their combination has been studied. A brief
review of the present uncertainties on the neutrino and antineutrino
cross-sections is also reported and their impact on the discovery potential
discussed
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