9,107 research outputs found
Ferromagnetic resonance imaging of Co films using magnetic resonance force microscopy
Lateral one-dimensional imaging of cobalt (Co) films by means of microscopic ferromagnetic resonance (FMR) detected using the magnetic resonance force microscope (MRFM) is demonstrated. A novel approach involving scanning a localized magnetic probe is shown to enable FMR imaging in spite of the broad resonance linewidth. We introduce a spatially selective local field by means of a small, magnetically polarized spherical crystallite of yttrium iron garnet (YIG). Using MRFM-detected FMR signals from a sample consisting of two Co films, we can resolve the ∼20 μm lateral separation between the films. The results can be qualitatively understood by consideration of the calculated spatial profiles of the magnetic field generated by the YIG sphere
Fracture toughness and crack-resistance curve behavior in metallic glass-matrix composites
Nonlinear-elastic fracture mechanics methods are used to assess the fracture toughness of bulk metallic glass (BMG) composites; results are compared with similar measurements for other monolithic and composite BMG alloys. Mechanistically, plastic shielding gives rise to characteristic resistance-curve behavior where the fracture resistance increases with crack extension. Specifically, confinement of damage by second-phase dendrites is shown to result in enhancement of the toughness by nearly an order of magnitude relative to unreinforced glass
Inhomogeneous Low Frequency Spin Dynamics in La_{1.65}Eu_{0.2}Sr_{0.15}CuO_4
We report Cu and La nuclear magnetic resonance (NMR) measurements in the
title compound that reveal an inhomogeneous glassy behavior of the spin
dynamics. A low temperature peak in the La spin lattice relaxation rate and the
``wipeout'' of Cu intensity both arise from these slow electronic spin
fluctuations that reveal a distribution of activation energies. Inhomogeneous
slowing of spin fluctuations appears to be a general feature of doped lanthanum
cuprate.Comment: 4 pages, 2 figures. Very slight modifications to figure
Gust-Load Alleviation of a Flexible Aircraft using a Disturbance Observer
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143016/1/6.2017-1718.pd
A Calculation of Baryon Diffusion Constant in Hot and Dense Hadronic Matter Based on an Event Generator URASiMA
We evaluate thermodynamical quantities and transport coefficients of a dense
and hot hadronic matter based on an event generator URASiMA (Ultra-Relativistic
AA collision Simulator based on Multiple Scattering Algorithm). The statistical
ensembles in equilibrium with fixed temperature and chemical potential are
generated by imposing periodic boundary condition to the simulation of URASiMA,
where energy density and baryon number density is conserved. Achievement of the
thermal equilibrium and the chemical equilibrium are confirmed by the common
value of slope parameter in the energy distributions and the saturation of the
numbers of contained particles, respectively. By using the generated ensembles,
we investigate the temperature dependence and the chemical potential dependence
of the baryon diffusion constant of a dense and hot hadronic matter.Comment: 15 pages, 5 figures, LaTeX2
From product dispensing to patient care: The role of the pharmacist in providing pharmaceutical care as part of an integrated disease management approach
During the past decade, the profession of pharmacy has changed dramatically. The Doctor of Pharmacy degree has replaced the Bachelor of Science degree as the first professional degree offered at most accredited U.S. pharmacy schools. Advanced clinical training is now a mainstay of pharmacy training, and this has enabled pharmacists to contribute to disease management efforts. In addition, technological improvements in prescription processing have afforded pharmacists more time to participate in disease management activities. This paper describes how the role of the pharmacist has changed and reviews the results of programs involving pharmacists as disease management providers in the areas of asthma, hypertension, diabetes, and hyperlipidemia. Pharmacists\u27 contributions in various practice settings are also discussed
An extreme [OIII] emitter at : a low metallicity Lyman continuum source
[Abridged] We investigate the physical properties of a Lyman continuum
emitter candidate at with photometric coverage from to MIPS
24m band and VIMOS/VLT and MOSFIRE/Keck spectroscopy. Investigation of the
UV spectrum confirms a direct spectroscopic detection of the Lyman continuum
emission with . Non-zero Ly flux at the systemic redshift and
high Lyman- escape fraction suggest a low HI column density. The weak C
and Si low-ionization absorption lines are also consistent with a low covering
fraction along the line of sight. The
[OIII] equivalent width is one of the
largest reported for a galaxy at
(, rest-frame) and the NIR spectrum shows that this is mainly due to an
extremely strong [OIII] emission. The large observed [OIII]/[OII] ratio ()
and high ionization parameter are consistent with prediction from
photoionization models in case of a density-bounded nebula scenario.
Furthermore, the
is
comparable to recent measurements reported at , in the reionization
epoch. We also investigate the possibility of an AGN contribution to explain
the ionizing emission but most of the AGN identification diagnostics suggest
that stellar emission dominates instead. This source is currently the first
high- example of a Lyman continuum emitter exhibiting indirect and direct
evidences of a Lyman continuum leakage and having physical properties
consistent with theoretical expectation from Lyman continuum emission from a
density-bounded nebula.Comment: 14 pages, 11 figures, accepted for publication in A&A. Minor
modifications, Figure 2 updated, Figure 9 adde
Hubble imaging of the ionizing radiation from a star-forming galaxy at z=3.2 with fesc>50%
Star-forming galaxies are considered to be the leading candidate sources that
dominate the cosmic reionization at z>7, and the search for analogs at moderate
redshift showing Lyman continuum (LyC) leakage is currently a active line of
research. We have observed a star-forming galaxy at z=3.2 with Hubble/WFC3 in
the F336W filter, corresponding to the 730-890A rest-frame, and detect LyC
emission. This galaxy is very compact and also has large Oxygen ratio
[OIII]5007/[OII]3727 (>=10). No nuclear activity is revealed from
optical/near-infrared spectroscopy and deep multi-band photometry (including
the 6Ms X-ray, Chandra). The measured escape fraction of ionizing radiation
spans the range 50-100\%, depending on the IGM attenuation. The LyC emission is
detected at S/N=10 with m(F336W)=27.57+/-0.11 and it is spatially unresolved,
with effective radius R_e<200pc. Predictions from photoionization and radiative
transfer models are in line with the properties reported here, indicating that
stellar winds and supernova explosions in a nucleated star-forming region can
blow cavities generating density-bounded conditions compatible with optically
thin media. Irrespective to the nature of the ionizing radiation, spectral
signatures of these sources over the entire electromagnetic spectrum are of
central importance for their identification during the epoch of reionization,
when the LyC is unobservable. Intriguingly, the Spitzer/IRAC photometric
signature of intense rest-frame optical emissions ([OIII]+Hbeta) observed
recently at z~7.5-8.5 is similar to what is observed in this galaxy. Only the
James Webb Space Telescope will measure optical line ratios at z>7 allowing a
direct comparison with lower redshift LyC emitters, as reported here.Comment: 6 pages, 5 figures, ApJ submitted (comments welcome
A New Scintillator Tile/Fiber Preshower Detector for the CDF Central Calorimeter
A detector designed to measure early particle showers has been installed in
front of the central CDF calorimeter at the Tevatron. This new preshower
detector is based on scintillator tiles coupled to wavelength-shifting fibers
read out by multi-anode photomultipliers and has a total of 3,072 readout
channels. The replacement of the old gas detector was required due to an
expected increase in instantaneous luminosity of the Tevatron collider in the
next few years. Calorimeter coverage, jet energy resolution, and electron and
photon identification are among the expected improvements. The final detector
design, together with the R&D studies that led to the choice of scintillator
and fiber, mechanical assembly, and quality control are presented. The detector
was installed in the fall 2004 Tevatron shutdown and started collecting
colliding beam data by the end of the same year. First measurements indicate a
light yield of 12 photoelectrons/MIP, a more than two-fold increase over the
design goals.Comment: 5 pages, 10 figures (changes are minor; this is the final version
published in IEEE-Trans.Nucl.Sci.
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