892,402 research outputs found
Neutrino Event Rates from Gamma Ray Bursts
We recalculate the diffuse flux of high energy neutrinos produced by Gamma
Ray Bursts (GRB) in the relativistic fireball model. Although we confirm that
the average single burst produces only ~10^{-2} high energy neutrino events in
a detector with 1 km^2 effective area, i.e. about 10 events per year, we show
that the observed rate is dominated by burst-to-burst fluctuations which are
very large. We find event rates that are expected to be larger by one order of
magnitude, likely more, which are dominated by a few very bright bursts. This
greatly simplifies their detection.Comment: 14 pages, Latex2.09, uses aastex4.0 and epsf.sty, 3 postscript files.
Minor revisions. To be published in ApJ Letter
The university-related science institute as a technology transfer agency
University science center for government and industrial user
Two-dimensional anyons and the temperature dependence of commutator anomalies
The temperature dependence of commutator anomalies is discussed on the
explicit example of particular (anyonic) field operators in two dimensions. The
correlation functions obtained show that effects of the non-zero temperature
might manifest themselves not only globally but also locally.Comment: 11 pages, LaTe
Radio frequency coaxial high pass filter Patent
Radio frequency coaxial filter to provide dc isolation and low frequency signal rejection in audio rang
Measurements of surface-pressure and wake-flow fluctuations in the flow field of a whitcomb supercritical airfoil
Measurements of surface pressure and wake flow fluctuations were made as part of a transonic wind tunnel investigation into the nature of a supercritical airfoil flow field. Emphasis was on a range of high subsonic Mach numbers and moderate lift coefficients corresponding to the development of drag divergence and buffeting. Fluctuation data were analyzed statistically for intensity, frequency content, and spatial coherence. Variations in these parameters were correlated with changes in the mean airfoil flow field
Handbook explaining the fundamentals of nuclear and atomic physics
Indoctrination document presents nuclear, reactor, and atomic physics in an easy, straightforward manner. The entire subject of nuclear physics including atomic structure ionization, isotopes, radioactivity, and reactor dynamics is discussed
PP-waves with torsion and metric-affine gravity
A classical pp-wave is a 4-dimensional Lorentzian spacetime which admits a
nonvanishing parallel spinor field; here the connection is assumed to be
Levi-Civita. We generalise this definition to metric compatible spacetimes with
torsion and describe basic properties of such spacetimes. We use our
generalised pp-waves for constructing new explicit vacuum solutions of
quadratic metric-affine gravity.Comment: 17 pages, LaTeX2
Aerodynamic characteristics of an F-8 aircraft configuration with a variable camber wing at Mach numbers from 0.70 to 1.15
A 0.1-scale model of an F-8 aircraft was tested in the Ames 14-Foot Transonic Wind Tunnel at Mach numbers from 0.7 to 1.15. Angle of attack was varied from -2 deg. to 22 deg. at sideslip angles of 0 deg and -5 deg. Reynolds number, dictated by the atmospheric stagnation pressure, varied with Mach number from 3.4 to 4.0 million based on mean aerodynamic chord. The model was configured with a wing designed to simulate the downward deflection of the leading and trailing edges of an advanced-technology-conformal-variable camber wing. This wing was also equipped with conventional (simple hinge) flaps. In addition, the model was tested with the basic F-8 wing to provide a reference for extrapolating to flight data. In general, at all Mach numbers the use of conformal flap deflections at both the leading edge and trailing edge resulted in slightly higher maximum lift coefficients and lower drag coefficients than with the use of simple hinge flaps. There were also found to be small improvements in the pitching-moment characteristics with the use of conformal flaps
On the Interaction Between Cosmic Rays and Dark Matter Molecular Clouds - II. The Age Distribution of Cosmic Ray Electrons
We explore further the proposal in paper I of this series that the
confinement time of cosmic ray nuclei in the Milky Way is determined by their
interaction with dark matter molecular clouds rather than by their escape from
the halo, as is assumed in conventional models of cosmic ray propagation. The
same proposal can be made for cosmic ray electrons. This proposal leads to a
specific age distribution for the electrons which is in agreement with Tang's
(1984) observations of the electron spectrum at high energies but not with
Nishimura et al's (1980) earlier data, which lead to a flatter spectrum.
However, the simplest leaky box and diffusion models disagree with both sets of
data so that our trapping model is supported if Tang's data are correct.Comment: 7 pages, no figures, using MNRAS latex styl
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