26,265 research outputs found
Development and evaluation of infrared sensitive image sensors for space astronomy
The experimental development and evaluation of infrared vidicons for use in solving high precision high flux broadband astronomical problems are discussed. Data cover the EOS, silicon, and doped germanium vidicons. Results are graphed and problems encountered using the vidicons in electrical cameras are reported
Effect of regression to the mean on decision making in health care
Knowledge of regression to the mean can help with everything from interpreting test results to improving your career prospects. All healthcare professionals should be aware of its implication
Obliquities of Kepler Stars: Comparison of Single- and Multiple-Transit Systems
The stellar obliquity of a transiting planetary system can be constrained by
combining measurements of the star's rotation period, radius, and projected
rotational velocity. Here we present a hierarchical Bayesian technique for
recovering the obliquity distribution of a population of transiting planetary
systems, and apply it to a sample of 70 Kepler Objects of Interest. With ~95%
confidence we find that the obliquities of stars with only a single detected
transiting planet are systematically larger than those with multiple detected
transiting planets. This suggests that a substantial fraction of Kepler's
single-transiting systems represent dynamically hotter, less orderly systems
than the "pancake-flat" multiple-transiting systems.Comment: 8 pages, 7 figures, accepted to Ap
Velocity dispersions in galaxies: 1: The SO galaxy NGC 7332
A Coude spectrum of the SO galaxy NGC 7332 with 0.9 A resolution from 4186 to 4364 A was obtained with the SEC vidicon television camera and the Hale telescope. Comparisons with spectra of G and K giant stars, numerically broadened for various Maxwellian velocity distributions, give a dispersion velocity in the line of sight of 160 + or - 20 km/sec with the best fit at G8III. The dispersion appears to be constant within + or - 35 km/sec out to 1.4 kpc (H = 100 km/sec/mpc). After correction for projection, the rotation curve has a slope of 0.16 km/sec/pc at the center and a velocity of 130 km/sec at 1.4 kpc where it is still increasing. For an estimated effective radius of 3.5 kpc enclosing half the light, the virial theorem gives a mass of 1.4 x 10 to the 11th power solar masses if the mass-to-light ratio is constant throughout the galaxy. The photographic luminosity is 8.3 x 10 to the 9th power solar luminosities so that the M/L ratio is 17
Deligne-Beilinson cohomology and abelian link invariants: torsion case
For the abelian Chern-Simons field theory, we consider the quantum functional
integration over the Deligne-Beilinson cohomology classes and present an
explicit path-integral non-perturbative computation of the Chern-Simons link
invariants in , a toy example of 3-manifold with
torsion
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