Role of the cascade interactions on the multiplicity distribution in hadron-nucleus collisions

Multiplicity distribution in proton-nucleus (p-A) collisions are investigated by the use of the Monte Carlo event generator MCMHA which has been developed based on the multi-chain model. The comparisons between the calculational results of MCMHA and the data are made through the parameters of negative binomial distributions. We can find nice agreement between them. The interpretation for the difference in the behaviour of 1/k in the backward hemisphere between \(p(\bar p) - p\) andp-A collisions is presented. In this connection, we also discuss the multiplicity ration 〈N〉 _pA /〈N〉 _pN .     

How Should the Distance of Probability Assignments Be Judged?

It is shown that the l ₁-distance in the space of probability assignments on a finite set Ω provides a criterion to judge whether two assignments are too close to each other to be distinguished by a statistical test. The criterion is independent of the number of elements of Ω. Other notions of distance are also discussed.     

Spectroscopic characterization of a molecule with a weak bond: the BrOO radical

Pure rotational spectra of the BrOO radical for the 79Br and 81Br isotopomers have been observed using a Fourier transform microwave spectrometer. The radical was produced in a supersonic jet by discharging a mixture gas containing bromine and oxygen diluted in argon. A-type rotational transitions are observed for N" = 1-5, K(a) = 0 with spin doublings and hyperfine splittings due to the nuclear spin of the bromine atom. High-level ab initio calculations by RCCSD(T) and MRCI have also been performed, and results are compared with the experimental data. Molecular structure of BrOO has been discussed based on the present experimental data, supplemented by the tendency among the halogen peroxide series and the results of the ab initio calculations; the Br-O bond is found to be anomalously long and weak. Systematic comparisons with other halogen peroxides have revealed anomalous nature of the X-O (X = halogen atom) bonds for this series of radicals.     

Tunable mid-infrared,high-energy femtosecond laser source for glyco-protein structure analysis

We have developed a 6–12 μm mid-infrared (MIR) femtosecond laser source for glyco-protein structure analysis. The MIR femtosecond laser pulses are generated by a differential frequency generation (DFG) configuration with a combination of Ti:sapphire based regeneratively amplified femtosecond laser pulses (780 nm, 160 fs, 1 mJ) and a β-BaB₂O₄ (BBO) based optical parametric amplifier (OPA). The MIR pulse energy exceeds 4.5 μJ, where a glyco-protein molecule has resonant absorption lines due to the vibrational–rotational transitions. The pulse width is estimated to be less than 1 ps according to the cross correlation measurement between the two OPA output pulses. Using the MIR femtosecond laser pulses, we demonstrated photo-dissociation of the sialyl Lewis X (sLeX) proton added ion, which is the first time to the best of our knowledge. PACS 42.65.Re; 42.62.-b; 42.60.-b; 42.65.-k; 87.50     

Fokker–Planck Theory of Nonequilibrium Systems Governed by Hierarchical Dynamics

Dynamics of complex systems is often hierarchically organized on different time scales. To understand the physics of such hierarchy, here Brownian motion of a particle moving through a fluctuating medium with slowly varying temperature is studied as an analytically tractable example, and a kinetic theory is formulated for describing the states of the particle. What is peculiar here is that the (inverse) temperature is treated as a dynamical variable. Dynamical hierarchy is introduced in conformity with the adiabatic scheme. Then, a new analytical method is developed to show how the Fokker–Planck equation admits as a stationary solution the Maxwellian distribution modulated by the temperature fluctuations, the distribution of which turns out to be determined by the drift term. A careful comment is also made on so-called superstatistics.     

A two dimensional liquid crystal simulation for thin film transistor liquid crystal displays

Abstract

A two-dimensional liquid crystal simulation, whose electrode configuration corresponds to that in a thin film transistor liquid crystal display (TFT-LCD), was carried out. Simulation results show that the lateral field between buslines and pixel electrode forms a reverse tilt domain. This reverse tilt domain leads to the disclination on the pixel electrode. The distance from the pixel electrode edge to this disclination location depends on the dielectric anisotropy and elastic constant for the liquid crystal. A small dielectric anisotropy or large elastic constant makes this distance small.     

Experimental and computational study of intermolecular migration of N,N-dimethylcarbamoyl group from N(7) to N(1) on a 7-azaindoline derivative

N,N-Dimethylcarbamoylation of the anilinic nitrogen atom N(1) on the spiro 7-azaindoline consists of two steps. The first step is N,N-dimethylcarbamoylation of the pyridyl nitrogen atom N(7), leading to the formation of an isolable intermediate. The second step is intermolecular migration of the N,N-dimethylcarbamoyl group from the pyridyl nitrogen atom N(7) to the anilinic nitrogen atom N(1). We accomplished optimization of the reaction conditions based on the revealed reaction mechanism and a large scale synthesis of compound 3 in quantitative yield.