1,029 research outputs found
Limits on Electron Neutrino Disappearance from the KARMEN and LSND electron neutrino - Carbon Cross Section Data
This paper presents a combined analysis of the KARMEN and LSND nu_e-carbon
cross section measurements within the context of a search for nu_e
disappearance at high Delta m^2. KARMEN and LSND were located at 17.7 m and
29.8 m respectively from the neutrino source, so the consistency of the two
measurements, as a function of antineutrino energy, sets strong limits on
neutrino oscillations. Most of the allowed region from the nu_e disappearance
analysis of the Gallium calibration data is excluded at >95% CL and the best
fit point is excluded at 3.6. Assuming CPT conservation, comparisons
are also made to the oscillation analyses of reactor antineutrino data.Comment: Published versio
Using Reactors to Measure
A next-generation neutrino oscillation experiment using reactor neutrinos
could give important information on the size of mixing angle . The
motivation and goals for a new reactor measurement are discussed in the context
of other measurements using off-axis accelerator neutrino beams. The reactor
measurements give a clean measure of the mixing angle without ambiguities
associated with the size of the other mixing angles, matter effects, and
effects due to CP violation. The key question is whether a next-generation
experiment can reach the needed sensitivity goals to make a measurement for
at the 0.01 level. The limiting factors associated with
a reactor disappearance measurement are described with some ideas of how
sensitivities can be improved. Examples of possible experimental setups are
presented and compared with respect to cost and sensitivity
Predictability and hierarchy in Drosophila behavior
Even the simplest of animals exhibit behavioral sequences with complex
temporal dynamics. Prominent amongst the proposed organizing principles for
these dynamics has been the idea of a hierarchy, wherein the movements an
animal makes can be understood as a set of nested sub-clusters. Although this
type of organization holds potential advantages in terms of motion control and
neural circuitry, measurements demonstrating this for an animal's entire
behavioral repertoire have been limited in scope and temporal complexity. Here,
we use a recently developed unsupervised technique to discover and track the
occurrence of all stereotyped behaviors performed by fruit flies moving in a
shallow arena. Calculating the optimally predictive representation of the fly's
future behaviors, we show that fly behavior exhibits multiple time scales and
is organized into a hierarchical structure that is indicative of its underlying
behavioral programs and its changing internal states
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