The all-particle spectrum of primary cosmic rays in the wide energy range from 10^14 eV to 10^17 eV observed with the Tibet-III air-shower array

We present an updated all-particle energy spectrum of primary cosmic rays in a wide range from 10^14 eV to 10^17 eV using 5.5 times 10^7 events collected in the period from 2000 November through 2004 October by the Tibet-III air-shower array located at 4300 m above sea level (atmospheric depth of 606 g/cm^2). The size spectrum exhibits a sharp knee at a corresponding primary energy around 4 PeV. This work uses increased statistics and new simulation calculations for the analysis. We performed extensive Monte Carlo calculations and discuss the model dependences involved in the final result assuming interaction models of QGSJET01c and SIBYLL2.1 and primary composition models of heavy dominant (HD) and proton dominant (PD) ones. Pure proton and pure iron primary models are also examined as extreme cases. The detector simulation was also made to improve the accuracy of determining the size of the air showers and the energy of the primary particle. We confirmed that the all-particle energy spectra obtained under various plausible model parameters are not significantly different from each other as expected from the characteristics of the experiment at the high altitude, where the air showers of the primary energy around the knee reaches near maximum development and their features are dominated by electromagnetic components leading to the weak dependence on the interaction model or the primary mass. This is the highest-statistical and the best systematics-controlled measurement covering the widest energy range around the knee energy region.Comment: 19 pages, 20 figures, accepted by Ap

Calculation method for computer-generated holograms with cylindrical basic object light by using a graphics processing unit

It takes an enormous amount of time to calculate a computer-generated hologram (CGH). A fast calculation method for a CGH using precalculated object light has been proposed in which the light waves of an arbitrary object are calculated using transform calculations of the precalculated object light. However, this method requires a huge amount of memory. This paper proposes the use of a method that uses a cylindrical basic object light to reduce the memory requirement. Furthermore, it is accelerated by using a graphics processing unit (GPU). Experimental results show that the calculation speed on a GPU is about 65 times faster than that on a CPU. (C) 2011 Optical Society of Americ

Electrochemically Controlled 2D Assembly of Paddle-Wheel Diruthenium Complexes on the Au(111) Surface and Identification of Their Redox States

The 2D molecular assemblies of chloride-coordinated mixed-valence diruthenium complexes, each possessing phenyl, naphtyl, or anthracenyl moieties, were examined on an Au(111) at electrochemical interface. In situ scanning tunneling microscopy images revealed a clear dependence of the molecular assembly on both the nature of the aryl functional groups and on the redox state of the dinuclear ruthenium complex, either chloride-coordinated Ru^II/Ru^III or noncoordinated Ru^II/Ru^II. At potentials where the Ru^II/Ru^III and Ru^II/Ru^II redox states were in equilibrium, two distinct redox states were clearly identified at the single-molecular level. We found that manipulating both the electrochemical potential and the aryl functional group substitution was important for controlling the 2D molecular assembly of a chloride-coordinated diruthenium complex on an Au(111) surface