167,985 research outputs found
IceCube Sterile Neutrino Searches
Anomalies in short baseline experiments have been interpreted as evidence for
additional neutrino mass states with large mass splittings from the known,
active flavors. This explanation mandates a corresponding signature in the muon
neutrino disappearance channel, which has yet to be observed. Searches for muon
neutrino disappearance at the IceCube neutrino telescope presently provide the
strongest limits in the space of mixing angles for eV-scale sterile neutrinos.
This proceeding for the Very Large Volume Neutrino Telescopes (VLVnT) Workshop
summarizes the IceCube analyses that have searched for sterile neutrinos and
describes ongoing work toward enhanced, high-statistics sterile neutrino
searches.Comment: Proceeding for the VLVNT2018 Conferenc
Dynamical Pion Collapse and the Coherence of Conventional Neutrino Beams
In this paper we consider the coherence properties of neutrinos produced by
the decays of pions in conventional neutrino beams. Using a multi-particle
density matrix formalism we derive the oscillation probability for neutrinos
emitted by a decaying pion in an arbitrary quantum state. Then, using methods
from decoherence theory we calculate the pion state which evolves through
interaction with decay-pipe gases in a typical accelerator neutrino experiment.
These two ingredients are used to obtain the distance scales for neutrino beam
coherence loss. We find that for the known neutrino mass splittings, no
non-standard oscillation effects are expected on terrestrial baselines. Heavy
sterile neutrinos may experience terrestrial loss of coherence, and we
calculate both the distance over which this occurs and the energy resolution
required to observe the effect. By treating the pion-muon-neutrino-environment
system quantum mechanically, neutrino beam coherence properties are obtained
without assuming arbitrary spatial or temporal scales at the neutrino
production vertex.Comment: 13 pages, 10 figures. v2: Minor typographical corrections v3:
Accepted for publication in Phys.Rev.
Effect of Culture Environment Upon Sporangium and Zoospore Production of Three Species of Phytophthora
New meanings from old buildings
The three modest house projects described here are by three fellow travellers — the two authors and David Lea — interested in the Organic side of Modernism. Conversational partners who have worked together in various capacities over many years, they share a common conviction about ‘working with the given
Vibrational transfer functions for base excited systems
Computer program GD203 develops transfer functions to compute governing vibration environment for complex structures subjected to a base motion
Surface brightness measurements for APM galaxies
This paper considers some simple surface brightness (SB) estimates for
galaxies in the Automated Plate Measuring Machine (APM) catalogue in order to
derive homogeneous SB data for a very large sample of faint galaxies. The
isophotal magnitude and area are used to estimate the central surface
brightness and total magnitude based on the assumption of an exponential SB
profile. The surface brightness measurements are corrected for field effects on
each UK Schmidt plate and the zero-point of each plate is adjusted to give a
uniform sample of SB and total magnitude estimates over the whole survey.
Results are obtained for 2.4 million galaxies with blue photographic magnitudes
brighter than b_J = 20.5 covering 4300 deg^2 in the region of the south
galactic cap. Almost all galaxies in our sample have central surface brightness
in the range 20 to 24 b_J mag per arcsec^2. The SB measurements we obtain are
compared to previous SB measurements and we find an acceptable level of error
of +/- 0.2 b_J mag per arcsec^2. The distribution of SB profiles is considered
for different galaxy morphologies for the bright APM galaxies. We find that
early-type galaxies have more centrally concentrated profiles.Comment: 14 pages, 17 figures, accepted for publication in MNRA
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