4,798 research outputs found
Branching Fractions for chi_cJ -\u3e p p-bar pi^0, p p-bar eta, and p p-bar omega
Using a sample of 25.9 million psi(2S) decays acquired with the CLEO-c detector at the CESR e^+e^- collider, we report branching fractions for the decays chi_cJ -\u3e p p-bar pi^0, p p-bar eta, and p p-bar omega, with J=0,1,2. Our results for B(chi_cJ-\u3e p p-bar pi^0) and B(chi_cJ-\u3e p p-bar eta) are consistent with, but more precise than, previous measurements. Furthermore, we include the first measurement of B(chi_cJ-\u3e p p-bar omega)
A User\u27s Manual for: A Clear Sky Solar Radiation Generator for the Personal Computer
Occasional Papers in Geography Publication No. 3
This program is primarily designed as an interactive instructional aid for students concerned with select aspects of shortwave radiation climatology. On the basis of user supplied temporal and geographic information the algorithm will produce instantaneous values of diffuse, direct, global, reflected, net shortwave and extraterrestrial radiation. Daily totals are also generated by numerical approximation of the area under the curve as described by each of these quantities. In addition, an optional routine to compute the instantaneous values of solar elevations and azimuths is included to further define the nature of astronomical relationships for the site under investigation. The overall structure of the program is such that the appropriate variables can be easily and conveniently manipulated to provide an accurate estimate of the shortwave radiative balance at a given point with a minimal knowledge of the relevant mathematics and of FORTRAN computer programming. It is hoped that the interested student will investigate the range of possibilities offered by this routine and use it as a stepping stone to the understanding of the many fundamental concepts involved in shortwave radiative transfer and its geographical distribution.https://pdxscholar.library.pdx.edu/geog_occasionalpaper/1001/thumbnail.jp
Ground-based detection of a vibration-rotation line of HD in Orion
The v =1-0 R(5) line of HD at 2.46um has been detected at the position of
brightest line emission of shocked H2 in the Orion Molecular Cloud. The flux in
this HD line, when compared to that of the previously detected HD 0--0 R(5)
line at 19.43um, suggests that, like the v=1 levels of H2, the v=1 levels of HD
are populated in LTE, despite their much higher rates of spontaneous emission
compared to H2. The higher than expected population of vibrationally excited HD
may be due to chemical coupling of HD to H2 via the reactive collisions HD + H
H2 + D in the shocked gas. The deuterium abundance implied by the
strengths of these lines relative to those of H2 is (5.1 pm 1.9 x 10^-6.Comment: 9 pages, 2 figures, Proceedings of the Conference on "Deuterium in
the Universe," to be published in Planetary and Space Science
The Cleo III Ring Imaging Cherenkov Detector
The CLEO detector has been upgraded to include a state of the art particle
identification system, based on the Ring Imaging Cherenkov Detector (RICH)
technology, in order to take data at the upgraded CESR electron positron
collider. The expected performance is reviewed, as well as the preliminary
results from an engineering run during the first few months of operation of the
CLEO III detector.Comment: 5 pages, 2 Figures Talk given by M. Artuso at 8th Pisa Meeting on
Advanced Detectors, May 200
Performance of the CLEO III LiF-TEA Ring Imaging Cherenkov Detector in a High Energy Muon Beam
The CLEO III Ring Imaging Cherenkov detector uses LiF radiators to generate Cherenkov photons which are then detected by proportional wire chambers using a mixture of CH and TEA gases. The first two photon detector modules which were constructed, were taken to Fermilab and tested in a beam dump that provided high momentum muons. We report on results using both plane and sawtooth shaped radiators. Specifically, we discuss the number of photoelectrons observed per ring and the angular resolution. The particle separation ability is shown to be sufficient for the physics of CLEO III
Optimum Monte Carlo Simulations: Some Exact Results
We obtain exact results for the acceptance ratio and mean squared
displacement in Monte Carlo simulations of the simple harmonic oscillator in
dimensions. When the trial displacement is made uniformly in the radius, we
demonstrate that the results are independent of the dimensionality of the
space. We also study the dynamics of the process via a spectral analysis and we
obtain an accurate description for the relaxation time.Comment: 17 pages, 8 figures. submitted to J. Phys.
Unexpected Effect of Internal Degrees of Freedom on Transverse Phonons in Supercooled Liquids
We show experimentally that in a supercooled liquid composed of molecules
with internal degrees of freedom the internal modes contribute to the frequency
dependent shear viscosity and damping of transverse phonons, which results in
an additional broadening of the transverse Brillouin lines. Earlier, only the
effect of internal modes on the frequency dependent bulk viscosity and damping
of longitudinal phonons was observed and explained theoretically in the limit
of weak coupling of internal degrees of freedom to translational motion. A new
theory is needed to describe this new effect. We also demonstrate, that the
contributions of structural relaxation and internal processes to the width of
the Brillouin lines can be separated by measurements under high pressure
Construction, Pattern Recognition and Performance of the CLEO III LiF-TEA RICH Detector
We briefly describe the design, construction and performance of the LiF-Tea RICH detector built to identify charged particles in the CLEO III experiment. Excellent pion/kaon separation is demonstrated
The Cleo Rich Detector
We describe the design, construction and performance of a Ring Imaging Cherenkov Detector (RICH) constructed to identify charged particles in the CLEO experiment. Cherenkov radiation occurs in LiF crystals, both planar and ones with a novel ``sawtooth\u27\u27-shaped exit surface. Photons in the wavelength interval 135--165 nm are detected using multi-wire chambers filled with a mixture of methane gas and triethylamine vapor. Excellent pion/kaon separation is demonstrated
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