717 research outputs found
EHR-Based Care Coordination Performance Measures in Ambulatory Care
Describes electronic health record-based measures for assessing coordination in referrals, including information communicated with referral, communication to patient, and specialist report to primary care physician. Offers preliminary evaluation findings
An Imaging Fabry-Perot System for the Robert Stobie Spectrograph on the Southern African Large Telescope
We present the design of the Fabry-Perot system of the Robert Stobie
Spectrograph on the 10-meter class Southern African Large Telescope and its
characterization as measured in the laboratory. This system provides
spectroscopic imaging at any desired wavelength spanning a bandpass 430 - 860
nm, at four different spectral resolving powers ranging from 300 to 9000. Our
laboratory tests revealed a wavelength dependence of the etalon gap and
parallelism with a maximum variation between 600 - 720 nm that arises because
of the complex structure of the broadband multi-layer dielectric coatings. We
also report an unanticipated optical effect of this multi-layer coating
structure that produces a significant, and wavelength dependent, change in the
apparent shape of the etalon plates. This change is caused by two effects: the
physical non-uniformities or thickness variations in the coating layers, and
the wavelength dependence of the phase change upon refection that can amplify
these non-uniformities. We discuss the impact of these coating effects on the
resolving power, finesse, and throughput of the system. This Fabry-Perot system
will provide a powerful tool for imaging spectroscopy on one of the world's
largest telescopes.Comment: 17 pages, 14 figures, accepted for publication in The Astronomical
Journa
Riccati parameter modes from Newtonian free damping motion by supersymmetry
We determine the class of damped modes \tilde{y} which are related to the
common free damping modes y by supersymmetry. They are obtained by employing
the factorization of Newton's differential equation of motion for the free
damped oscillator by means of the general solution of the corresponding Riccati
equation together with Witten's method of constructing the supersymmetric
partner operator. This procedure leads to one-parameter families of (transient)
modes for each of the three types of free damping, corresponding to a
particular type of %time-dependent angular frequency. %time-dependent,
antirestoring acceleration (adding up to the usual Hooke restoring
acceleration) of the form a(t)=\frac{2\gamma ^2}{(\gamma t+1)^{2}}\tilde{y},
where \gamma is the family parameter that has been chosen as the inverse of the
Riccati integration constant. In supersymmetric terms, they represent all those
one Riccati parameter damping modes having the same Newtonian free damping
partner modeComment: 6 pages, twocolumn, 6 figures, only first 3 publishe
Optical analog of Rabi oscillation suppression due to atomic motion
The Rabi oscillations of a two-level atom illuminated by a laser on resonance
with the atomic transition may be suppressed by the atomic motion through
averaging or filtering mechanisms. The optical analogs of these velocity
effects are described. The two atomic levels correspond in the optical analogy
to orthogonal polarizations of light and the Rabi oscillations to polarization
oscillations in a medium which is optically active, naturally or due to a
magnetic field. In the later case, the two orthogonal polarizations could be
selected by choosing the orientation of the magnetic field, and one of them be
filtered out. It is argued that the time-dependent optical polarization
oscillations or their suppression are observable with current technology.Comment: 10 pages, 10 figure
Atom laser dynamics in a tight-waveguide
We study the transient dynamics that arise during the formation of an atom
laser beam in a tight waveguide. During the time evolution the density profile
develops a series of wiggles which are related to the diffraction in time
phenomenon. The apodization of matter waves, which relies on the use of smooth
aperture functions, allows to suppress such oscillations in a time interval,
after which there is a revival of the diffraction in time. The revival time
scale is directly related to the inverse of the harmonic trap frequency for the
atom reservoir.Comment: 6 pages, 5 figures, to be published in the Proceedings of the 395th
WE-Heraeus Seminar on "Time Dependent Phenomena in Quantum Mechanics ",
organized by T. Kramer and M. Kleber (Blaubeuren, Germany, September 2007
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