43,249 research outputs found
Construction of a cosmic ray air shower telescope
The telescope under construction is mainly for the purpose of locating the arrival directions of energetic particles and quanta which generate air showers of sizes 10 to the 5th power to 10 to the 6th power. Both fast timing method and visual track method are incorporated in determining the arrival directions. The telescope is composed of four stations using scintillators and neon flash tubes as detectors. The system directional resolution is better than 1.5 deg
Hamiltonian approach to slip-stacking dynamics
Hamiltonian dynamics has been applied to study the slip-stacking dynamics.
The canonical-perturbation method is employed to obtain the second-harmonic
correction term in the slip-stacking Hamiltonian. The Hamiltonian approach
provides a clear optimal method for choosing the slip-stacking parameter and
improving stacking efficiency. The dynamics are applied specifically to the
Fermilab Booster-Recycler complex. The dynamics can also be applied to other
accelerator complexes.Comment: 10 p
Measurement of shower electrons and muons using a small air shower array
A small air shower array has been used to measure the size spectrum of air showers at sea level in the size range 6.10 to the 3rd power to 10 to the 6th power. The result fitted with the power law gives an index 2.79 + or - 0.11 for the differential spectrum. Lateral distribution of electrons fitted with the well known NKG function results in an age parameter s = 1.35 for core distances less than 30m and s = 0.8 for longer core distances. Lateral distribution of muons follows the general shape of Greisen's relation but is much higher in intensity. Muon and electron densities at the same observation point are also compared
Improved Dark Energy Detection through the Polarization-assisted WMAP-NVSS ISW Correlation
Integrated Sachs-Wolfe (ISW) effect can be estimated by cross-correlating
Cosmic Microwave Background (CMB) sky with tracers of the local matter
distribution. At late cosmic time, the dark energy induced decay of gravitation
potential generates a cross-correlation signal on large angular scales. The
dominant noise are the intrinsic CMB anisotropies from the inflationary epoch.
In this Letter we use CMB polarization to reduce this intrinsic noise. We
cross-correlate the microwave sky observed by Wilkinson Microwave Anisotropy
Probe (WMAP) with the radio source catalog compiled by NRAO VLA Sky Survey
(NVSS) to study the efficiency of the noise suppression . We find that the
error bars are reduced about 5-12 %, improving the statistical power.Comment: 10 pages, 2 figure
Factor structure and psychometric properties of the body appreciation scale-2 in university students in Hong Kong
Previous studies have suggested that there may not be cross-cultural equivalence in the factor structure of body appreciation. Here, we examine the conceptual equivalence of a Chinese (Cantonese) translation of the Body Appreciation Scale-2 (BAS-2; Tylka & Wood-Barcalow, 2015b), a newly-developed measure of body appreciation. Participants were 457 women and 417 men from a university in Hong Kong. The results of exploratory factor analyses showed that, like its English version, the Chinese BAS-2 had a one-dimensional structure. Body appreciation scores had good internal consistency and were also significantly associated with respondent body mass index, self-esteem, life satisfaction, and (in women) actual-ideal weight discrepancy. Men had significantly higher scores than women, while comparisons with data from Tylka and Wood-Barcalow (2015b) suggest that cross-cultural differences are small-to-moderate at best. The present findings suggest that the BAS-2 may prove to be a useful tool for the assessment of body appreciation across cultures
A mini-array for large air showers
A mini-array that utilizes the Linsley effect is proposed for the measurement of large air showers. An estimate of the detectable shower rates for various shower sizes is made. Details of the detection and data collection systems are also described
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