15,379 research outputs found
Maxwell's Equations in a Uniformly Rotating Dielectric Medium and the Wilson-Wilson Experiment
This note offers a conceptually straightforward and efficient way to
formulate and solve problems in the electromagnetics of moving media based on a
representation of Maxwell's equations in terms of differential forms on
spacetime together with junction conditions at moving interfaces. This
framework is used to address a number of issues that have been discussed
recently in this journal about the theoretical description underlying the
interpretation of the Wilson-Wilson experiment.Comment: 16 pages, 2 figure
Using White Dish CMB Anisotropy Data to Probe Open and Flat-Lambda CDM Cosmogonies
We use data from the White Dish experiment to set limits on cosmic microwave
background radiation anisotropies in open and spatially-flat-Lambda cold dark
matter cosmogonies. We account for the White Dish calibration uncertainty, and
marginalize over the offset and gradient removed from the data. Our 2-sigma
upper limits are larger than those derived previously. These upper limits are
consistent with those derived from the -DMR data for all models tested.Comment: 17 pages of latex. Uses aasms4.sty. 4 figures included. Submitted to
ApJ
Observational evidence for stochastic biasing
We show that the galaxy density in the Las Campanas Redshift Survey (LCRS)
cannot be perfectly correlated with the underlying mass distribution since
various galaxy subpopulations are not perfectly correlated with each other,
even taking shot noise into account. This rules out the hypothesis of simple
linear biasing, and suggests that the recently proposed stochastic biasing
framework is necessary for modeling actual data.Comment: 4 pages, with 2 figures included. Minor revisions to match accepted
ApJL version. Links and color fig at
http://www.sns.ias.edu/~max/r_frames.html or from [email protected]
Local u'g'r'i'z' Standard Stars in the Chandra Deep Field-South
Because several observing programs are underway in various spectral regimes
to explore the Chandra Deep Field South (CDF-S), the value of local photometric
standards is obvious. As part of an NOAO Surveys Program to establish
u'g'r'i'z' standard stars in the southern hemisphere, we have observed the
central region of the CDF-S to create local standards for use by other
investigators using these filters. As a courtesy, we present the CDF-S
standards to the public now, although the main program will not finish until
mid-2005.Comment: Accepted by AJ (scheduled for October 2003 issue). 26 pages, 5
tables, 5 figures. High resolution version of Figure 7 available at
http://home.fnal.gov/~dtucker/Southern_ugriz/index.htm
Spectrum of turbulence in a contracting stream
The spectrum concept is employed to study the selective effect of a stream contraction on the longitudinal and lateral turbulent velocity fluctuations of the stream. By a consideration of the effect of the stream contraction on a single plane sinusoidal disturbance wave, mathematically not dissimilar to a triply periodic disturbance treated by G. I. Taylor, the effect on the spectrum tensor of the turbulence and hence on the correlation tensor is determined
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