8,384 research outputs found
Considering Teaching Excellence in Higher Education: 2007-2013: A Literature Review Since the CHERI Report 2007
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The acceleration of energetic particles in the interplanetary medium by transit-time damping
Transit time damping is examined as a possible means for accelerating low energy particles in co-rotating streams and interstellar ions. Data show that: the protons in co-rotating streams may be accelerated by transient-time damping the small-scale variations in the field magnitude that are observed at a low level in the inner solar system. The interstellar ions may be accelerated by transit time damping large-scale field variations in the outer solar system
Solar modulation of galactic cosmic rays 4: Latitude dependent modulation
A numerical method is outlined for solving the equation which describes the solar modulation of cosmic rays in models where interplanetary conditions can vary with heliocentric latitude. As an illustration of the use of this method, it is shown how variations in the modulation with latitude could produce the small radial gradients in the intensity that were observed from the Pioneers 10 and 11 spacecraft
Muon ID- Taking Care of Lower Momenta Muons
In the Muon package under study, the tracks are extrapolated using an
algorithm which accounts for the magnetic field and the ionization (dE/dx). We
improved the calculation of the field dependent term to increase the muon
detection efficiency at lower momenta using a Runge-Kutta method. The muon
identification and hadron separation in b-bbar jets is reported with the
improved software. In the same framework, the utilization of the Kalman filter
is introduced. The principle of the Kalman filter is described in some detail
with the propagation matrix, with the Runge-Kutta term included, and the effect
on low momenta single muons particles is described.Comment: PDF,5pages,2 Figures,1 Table,Presented at the 2005 International
Linear Collider Physics and Detectors Workshop,Snowmass,Colorado,14-27 Aug.
2005, PSN1011 in the proceedin
Quiet-time electron increases, a measure of conditions in the outer solar system
One possible explanation for quiet-time electron increases, increases in the intensity of 3-12 MeV interplanetary electrons that have been reported by McDonald, Cline and Simnett, is discussed. It is argued that the electrons in quiet-time increases are galactic in origin, but that the observed increases are not the result of any variation in the modulation of these particles in the inner solar system. It is suggested instead that quiet-time increases may occur when more electrons than normal penetrate a modulating region that lies far beyond the orbit of earth. The number of electrons penetrating this region may increase when field lines that have experienced an unusually large random walk in the photosphere are carried by the solar wind out to the region. As evidence for this increased random walk, it is shown that five solar rotations before most of the quiet-time increases there is an extended period when the amplitude of the diurnal anisotropy, as is measured by the Deep River neutron monitor, is relatively low. Five rotations delay time implies that the proposed modulating region lies at approximately 30 AU from the Sun, assuming that the average solar wind speed is constant over this distance at approximately 400 km/sec
Radial gradients and anisotropies of cosmic rays in the interplanetary medium
Radial gradients and anisotropies of cosmic rays in interplanetary mediu
Electronic phase separation due to magnetic polaron formation in the semimetallic ferromagnet EuB - A weakly-nonlinear-transport study
We report measurements of weakly nonlinear electronic transport, as measured
by third-harmonic voltage generation , in the low-carrier density
semimetallic ferromagnet EuB, which exhibits an unusual magnetic ordering
with two consecutive transitions at \,K and \,K. Upon cooling in zero magnetic field through the ferromagnetic
transition, the dramatic drop in the linear resistivity at the upper transition
coincides with the onset of nonlinearity, and upon further cooling is
followed by a pronounced peak in at the lower transition
. Likewise, in the paramagnetic regime, a drop of the material's
magnetoresistance precedes a magnetic-field-induced peak in nonlinear
transport. A striking observation is a linear temperature dependence of
. We suggest a picture where at the upper transition
the coalescing MP form a conducting path giving rise to a strong
decrease in the resistance. The MP formation sets in at around \,K below which these entities are isolated and strongly fluctuating, while
growing in number. The MP then start to form links at , where
percolative electronic transport is observed. The MP merge and start forming a
continuum at the threshold . In the paramagnetic temperature regime
, MP percolation is induced by a magnetic field, and the
threshold accompanied by charge carrier delocalization occurs at a single
critical magnetization.Comment: to appear in J. Kor. Phys. Soc (ICM2012 conference contribution
Damping of high frequency waves in the solar wind
Cyclotron damping by suprathermal fluxes of protons and electrons in the interplanetary medium will greatly attenuate high frequency Alfven waves and whistler waves within distances 1 AU of the sun. Electrons with energies between 50 eV to 2 KeV are heated as a result of damping interplanetary whistler waves with frequencies 2 omega meson/2 pion 30 Hz in the frame of the solar wind. This heating may account, in part, for the observed suprathermal tail of solar wind electrons. Protons with energies approximately 50 KeV damp Alfven waves with frequencies .001 omega meson/2 pion .01 Hz. This damping mechanism may explain several features of a scatter free solar electron events and high intensity, anisotropic solar proton streams
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Methods and compositions for stimulating T-lymphocytes
Disclosed are methods, compositions, antibodies, and therapeutic kits for use in stimulating cytotoxic T-lymphocytes and generating immune responses against epitopes of protooncogenes. Novel peptides are described which have been shown to stimulate cytotoxic T-lymphocytes, and act as antigens in generation of oncogenic epitope-recognizing antibodies. Methods are disclosed for use in treating various proliferative disorders, and diagnosing HER-2/neu-containing cells; also disclosed are therapeutic kits useful in the treatment of cancer and production of potential anti-cancer vaccines.Board of Regents, University of Texas Syste
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