1,482 research outputs found
Establishing a Review Process to Evaluate Research Guides
Springshare\u27s LibGuide platform has become synonymous with online library pathfinders or research guides and instruction support. However, without oversight of the collection of guides and standards for their creation, unwieldy numbers and lack of uniformity prevail. The McGoogan Library of Medicine at the University of Nebraska Medical Center created a review process that not only governed the creation and approval of guides, but analyzed the usage and scope of guides that had already been created. This paper will outline the creation of standards and application of a review process to increase the value and relevance of guides
Duality between Electric and Magnetic Black Holes
A number of attempts have recently been made to extend the conjectured
duality of Yang Mills theory to gravity. Central to these speculations has been
the belief that electrically and magnetically charged black holes, the solitons
of quantum gravity, have identical quantum properties. This is not obvious,
because although duality is a symmetry of the classical equations of motion, it
changes the sign of the Maxwell action. Nevertheless, we show that the chemical
potential and charge projection that one has to introduce for electric but not
magnetic black holes exactly compensate for the difference in action in the
semi-classical approximation. In particular, we show that the pair production
of electric black holes is not a runaway process, as one might think if one
just went by the action of the relevant instanton. We also comment on the
definition of the entropy in cosmological situations, and show that we need to
be more careful when defining the entropy than we are in an asymptotically-flat
case.Comment: 23 pages, revtex, no figures. Major revision: two sections on the
electric Ernst solution adde
Radiative Capture of Tensor Polarized Deuterons on Hydrogen Isotopes
This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440
Effect of continuum couplings in fusion of halo Be on Pb around the Coulomb barrier
The effect of continuum couplings in the fusion of the halo nucleus Be
on Pb around the Coulomb barrier is studied using a three-body model
within a coupled discretised continuum channels (CDCC) formalism. We
investigate in particular the role of continuum-continuum couplings. These are
found to hinder total, complete and incomplete fusion processes. Couplings to
the projectile bound excited state redistribute the complete and
incomplete fusion cross sections, but the total fusion cross section remains
nearly constant. Results show that continuum-continuum couplings enhance the
irreversibility of breakup and reduce the flux that penetrates the Coulomb
barrier. Converged total fusion cross sections agree with the experimental ones
for energies around the Coulomb barrier, but underestimate those for energies
well above the Coulomb barrier.Comment: 15 pages, 7 figures, accepted in Phys. Rev.
On Modular Homology of Simplicial Complexes: Saturation
... homology, and these are the so-called saturated complexes. We show that certain conditions on the links of the complex imply saturation. We prove that Coxeter complexes and buildings are saturated
Tensor Polarized Deuteron Capture by the Hydrogen Isotopes
This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440
Tensor Polarized Deuteron Capture by the Hydrogen Isotopes
This research was sponsored by the National Science Foundation Grant NSF PHY 87-1440
Review article: MHD wave propagation near coronal null points of magnetic fields
We present a comprehensive review of MHD wave behaviour in the neighbourhood
of coronal null points: locations where the magnetic field, and hence the local
Alfven speed, is zero. The behaviour of all three MHD wave modes, i.e. the
Alfven wave and the fast and slow magnetoacoustic waves, has been investigated
in the neighbourhood of 2D, 2.5D and (to a certain extent) 3D magnetic null
points, for a variety of assumptions, configurations and geometries. In
general, it is found that the fast magnetoacoustic wave behaviour is dictated
by the Alfven-speed profile. In a plasma, the fast wave is focused
towards the null point by a refraction effect and all the wave energy, and thus
current density, accumulates close to the null point. Thus, null points will be
locations for preferential heating by fast waves. Independently, the Alfven
wave is found to propagate along magnetic fieldlines and is confined to the
fieldlines it is generated on. As the wave approaches the null point, it
spreads out due to the diverging fieldlines. Eventually, the Alfven wave
accumulates along the separatrices (in 2D) or along the spine or fan-plane (in
3D). Hence, Alfven wave energy will be preferentially dissipated at these
locations. It is clear that the magnetic field plays a fundamental role in the
propagation and properties of MHD waves in the neighbourhood of coronal null
points. This topic is a fundamental plasma process and results so far have also
lead to critical insights into reconnection, mode-coupling, quasi-periodic
pulsations and phase-mixing.Comment: 34 pages, 5 figures, invited review in Space Science Reviews => Note
this is a 2011 paper, not a 2010 pape
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