46,027 research outputs found
Probation training: the experience of teachers and learners
Original article can be found at: http://www.informaworld.com/ Copyright Informa / Taylor and Francis GroupQualifying training in probation is under review and likely to be substantially changed. This article draws on a small scale study of current training arrangements designed to explore the views of trainee probation officers, practice development assessors and university tutors regarding which elements of the current Diploma in Probation Studies framework most support learning. Their comments focus on the organisational ownership of training, time and learning, the teacher-learner relationship, teaching methods and equality of access. It is argued that probation training is best supported by a series of linked qualifications across grades, integrating practice-based and academic learning delivered through a 'blended learning' model.Peer reviewe
An unusual pi* shape resonance in the near-threshold photoionization of S(1) para-difluorobenzene
Previously reported dramatic changes in photoelectron angular distributions (PADs) as a function of photoelectron kinetic energy following the ionization of S1 p-difluorobenzene are shown to be explained by a shape resonance in the b(2g) symmetry continuum. The characteristics of this resonance are clearly demonstrated by a theoretical multiple-scattering treatment of the photoionization dynamics. New experimental data are presented which demonstrate an apparent insensitivity of the PADs to both vibrational motion and prepared molecular alignment, however, the calculations suggest that strong alignment effects may nevertheless be recognized in the detail of the comparison with experimental data. The apparent, but unexpected, indifference to vibrational excitation is rationalized by considering the nature of the resonance. The correlation of this shape resonance in the continuum with a virtual pi* antibonding orbital is considered. Because this orbital is characteristic of the benzene ring, the existence of similar resonances in related substituted benzenes is discussed.Bellm, SM: Davies, JA: Whiteside, PT; Guo, J: Powis, I; and Reid KL
A combined theoretical and experimental study of the low temperature properties of BaZrO3
Low temperature properties of BaZrO3 are revealed by combining experimental
techniques (X-ray diffraction, neutron scattering and dielectric measurements)
with theoretical first-principles-based methods (total energy and linear
response calculations within density functional theory, and effective
Hamiltonian approaches incorporating/neglecting zero-point phonon vibrations).
Unlike most of the perovskite systems, BaZrO3 does not undergo any
(long-range-order) structural phase transition and thus remains cubic and
paraelectric down to 2 K, even when neglecting zero-point phonon vibrations. On
the other hand, these latter pure quantum effects lead to a negligible thermal
dependency of the cubic lattice parameter below ~ 40 K. They also affect the
dielectricity of BaZrO3 by inducing an overall saturation of the real part of
the dielectric response, for temperatures below ~ 40 K. Two fine structures in
the real part, as well as in the imaginary part, of dielectric response are
further observed around 50-65 K and 15 K, respectively. Microscopic origins
(e.g., unavoidable defects and oxygen octahedra rotation occurring at a local
scale) of such anomalies are suggested. Finally, possible reasons for the facts
that some of these dielectric anomalies have not been previously reported in
the better studied KTaO3 and SrTiO3 incipient ferroelectrics are also
discussed.Comment: 8 pages, 5 figures, submitted to Physical Review
Spin-Excitation Mechanisms in Skyrme-Force Time-Dependent Hartree-Fock
We investigate the role of odd-odd (with respect to time inversion) couplings
in the Skyrme force on collisions of light nuclei, employing a fully
three-dimensional numerical treatment without any symmetry restrictions and
with modern Skyrme functionals. We demonstrate the necessity of these couplings
to suppress spurious spin excitations owing to the spin-orbit force in free
translational motion of a nucleus but show that in a collision situation there
is a strong spin excitation even in spin-saturated systems which persists in
the departing fragments. The energy loss is considerably increased by the
odd-odd terms
Heavy meson masses and decay constants from relativistic heavy quarks in full lattice QCD
We determine masses and decay constants of heavy-heavy and heavy-charm
pseudoscalar mesons as a function of heavy quark mass using a fully
relativistic formalism known as Highly Improved Staggered Quarks for the heavy
quark. We are able to cover the region from the charm quark mass to the bottom
quark mass using MILC ensembles with lattice spacing values from 0.15 fm down
to 0.044 fm. We obtain f_{B_c} = 0.427(6) GeV; m_{B_c} = 6.285(10) GeV and
f_{\eta_b} = 0.667(6) GeV. Our value for f_{\eta_b} is within a few percent of
f_{\Upsilon} confirming that spin effects are surprisingly small for heavyonium
decay constants. Our value for f_{B_c} is significantly lower than potential
model values being used to estimate production rates at the LHC. We discuss the
changing physical heavy-quark mass dependence of decay constants from
heavy-heavy through heavy-charm to heavy-strange mesons. A comparison between
the three different systems confirms that the B_c system behaves in some ways
more like a heavy-light system than a heavy-heavy one. Finally we summarise
current results on decay constants of gold-plated mesons.Comment: 16 pages, 12 figure
Boost-invariant mean field approximation and the nuclear Landau-Zener effect
We investigate the relation between time-dependent Hartree-Fock (TDHF) states
and the adiabatic eigenstates by constructing a boost-invariant single-particle
Hamiltonian. The method is numerically realized within a full three-dimensional
TDHF which includes all the terms of the Skyrme energy functional and without
any symmetry restrictions. The study of a free translational motion of a
nucleus demonstrates the validity of the concept of boost-invariant and
adiabatic TDHF states. The interpretation is further corroborated by the test
case of fusion of +. As a first
application, we present a study of the nuclear Landau-Zener effect on a
collision of +.Comment: 8 pages, 3 figure
Highly Improved Staggered Quarks on the Lattice, with Applications to Charm Physics
We use perturbative Symanzik improvement to create a new staggered-quark
action (HISQ) that has greatly reduced one-loop taste-exchange errors, no
tree-level order a^2 errors, and no tree-level order (am)^4 errors to leading
order in the quark's velocity v/c. We demonstrate with simulations that the
resulting action has taste-exchange interactions that are at least 3--4 times
smaller than the widely used ASQTAD action. We show how to estimate errors due
to taste exchange by comparing ASQTAD and HISQ simulations, and demonstrate
with simulations that such errors are no more than 1% when HISQ is used for
light quarks at lattice spacings of 1/10 fm or less. The suppression of (am)^4
errors also makes HISQ the most accurate discretization currently available for
simulating c quarks. We demonstrate this in a new analysis of the psi-eta_c
mass splitting using the HISQ action on lattices where a m_c=0.43 and 0.66,
with full-QCD gluon configurations (from MILC). We obtain a result of~111(5)
MeV which compares well with experiment. We discuss applications of this
formalism to D physics and present our first high-precision results for D_s
mesons.Comment: 21 pages, 8 figures, 5 table
Conceptual design of an airborne laser Doppler velocimeter system for studying wind fields associated with severe local storms
An airborne laser Doppler velocimeter was evaluated for diagnostics of the wind field associated with an isolated severe thunderstorm. Two scanning configurations were identified, one a long-range (out to 10-20 km) roughly horizontal plane mode intended to allow probing of the velocity field around the storm at the higher altitudes (4-10 km). The other is a shorter range (out to 1-3 km) mode in which a vertical or horizontal plane is scanned for velocity (and possibly turbulence), and is intended for diagnostics of the lower altitude region below the storm and in the out-flow region. It was concluded that aircraft flight velocities are high enough and severe storm lifetimes are long enough that a single airborne Doppler system, operating at a range of less than about 20 km, can view the storm area from two or more different aspects before the storm characteristics change appreciably
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