47,863 research outputs found
Observations of Large Scale Sidereal Anisotropy in 1 and 11 TeV cosmic rays from the MINOS experiment
The MINOS Near and Far Detectors are two large, functionally-identical,
steel-scintillating sampling calorimeters located at depths of 220 mwe and 2100
mwe respectively. The detectors observe the muon component of hadronic showers
produced from cosmic ray interactions with nuclei in the earth's atmosphere.
From the arrival direction of these muons, the anisotropy in arrival direction
of the cosmic ray primaries can be determined. The MINOS Near and Far Detector
have observed anisotropy on the order of 0.1% at 1 and 11 TeV respectively. The
amplitude and phase of the first harmonic at 1 TeV are
8.21.7(stat.) and (8.912.1(stat.)), and at
11 TeV are 3.80.5(stat.) and
(27.27.2(stat.)).Comment: 32nd International Cosmic Ray Conference, August 201
Search for the magnetic field of the O7.5 III star xi Persei
Cyclical wind variability is an ubiquitous but as yet unexplained feature
among OB stars. The O7.5 III(n)((f)) star xi Persei is the brightest
representative of this class on the Northern hemisphere. As its prominent
cyclical wind properties vary on a rotational time scale (2 or 4 days) the star
has been already for a long time a serious magnetic candidate. As the cause of
this enigmatic behavior non-radial pulsations and/or a surface magnetic field
are suggested. We present a preliminary report on our attempts to detect a
magnetic field in this star with high-resolution measurements obtained with the
spectropolarimeter Narval at TBL, France during 2 observing runs of 5 nights in
2006 and 5 nights in 2007. Only upper limits could be obtained, even with the
longest possible exposure times. If the star hosts a magnetic field, its
surface strength should be less than about 300 G. This would still be enough to
disturb the stellar wind significantly. From our new data it seems that the
amplitude of the known non-radial pulsations has changed within less than a
year, which needs further investigation.Comment: 2 pages, 6 figures, contributed poster at IAU Symposium 259 "Cosmic
Magnetic Fields: from Planets, to Stars and Galaxies", Tenerife, Spain,
November 3-7, 200
Drell-Yan process in soft-collinear effective theory near end-point
The Drell-Yan process is analyzed in soft-collinear effective theory near the
end-point region. It is assumed that the relevant final-state hadron energy
where is the momentum fraction transferred to the virtual photon
is the typical hadronic scale , thus no intermediate scale exists.
It is shown that this setup successfully reproduces the full theory results. We
also discuss the factorized soft Wilson lines for the Drell-Yan process.Comment: 18 pages, 6 figures. More discussions, references added. PRD accepted
versio
Sub-Poissonian Shot Noise In A Diffusive Conductor
A review is given of the shot-noise properties of metallic, diffusive
conductors. The shot noise is one third of the Poisson noise, due to the
bimodal distribution of transmission eigenvalues. The same result can be
obtained from a semiclassical calculation. Starting from Oseledec's theorem it
is shown that the bimodal distribution is required by Ohm's law.Comment: 9 pages, LaTeX, including 2 figure
Feed additives : annual report 2009 of the National Reference Laboratory
This report of the National Reference Laboratory (NRL) for feed additives describes the activties employed in 2010. The main tasks of the NRL are: giving assistance to the European Union Reference Laboratort (EU-RL) on their request and advice and support the competent authority, the Dutch Ministry of Economic Affairs, Agriculture and Innovation - Department of Food, Animal and Consumer (EL&I-VDC
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