41,756 research outputs found
Rotary target V-block
A device used in the optical alignment of machinery to maintain a measuring scale in the proper position for optical readings to be taken is described. The device consists of a block containing a notch in the shape of an inverted ""v'' and a rotatable plug positioned over the centerline of notch. The block is placed on the object to be aligned, the notch allows the block to be securely placed upon flat or curved surfaces. A weighted measuring scale is inserted through plug so that it contacts the object to be aligned. The scale and plug combination can be rotated so that the scale faces an optical aligning instrument. The instrument is then used in conjunction with the scale to measure the distance of the machinery from a reference plane
Testing the Equivalence Principle using Atomic Vacuum Energy Shifts
We consider possible tests of the Einstein Equivalence Principle for
quantum-mechanical vacuum energies by evaluating the Lamb shift transition in a
class of non-metric theories of gravity described by the \tmu formalism. We
compute to lowest order the associated red shift and time dilation parameters,
and discuss how (high-precision) measurements of these quantities could provide
new information on the validity of the equivalence principle.Comment: 4 pages, latex, epsf, 1 figur
Civic Engagement and Recent Immigrant Communities
Provides a step-by-step guide to developing strategies and planning efforts to strengthen immigrants' civic engagement , including suggested agendas, background materials, and discussion guides. Outlines considerations for planning and successful formats
Governing dynamics by squeezing in a system of cold trapped ions
We consider a system of laser-cooled ions in a linear harmonic trap and study
the phenomenon of squeezing exchange between their internal and motional
degrees of freedom. An interesting relation between the quantum noise reduction
(squeezing) and the dynamical evolution is found when the internal and motional
subsystems are prepared in properly squeezed (intelligent) states.
Specifically, the evolution of the system is fully governed by the relative
strengths of spectroscopic and motional squeezing, including the phenomenon of
total cancellation of the interaction when the initial squeezing parameters are
equal.Comment: REVTeX, 5 pages, 2 figures, to appear in Phys. Rev.
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