Thermodynamics of 2D string theory

We calculate the free energy, energy and entropy in the matrix quantum mechanical formulation of 2D string theory in a background strongly perturbed by tachyons with the imaginary Minkowskian momentum $\pm i/R$ (``Sine-Liouville'' theory). The system shows a thermodynamical behaviour corresponding to the temperature $T=1/(2\pi R)$. We show that the microscopically calculated energy of the system satisfies the usual thermodynamical relations and leads to a non-zero entropy.Comment: 13 pages, lanlmac; typos correcte

Photosensitive AlGaAs / GaAs Structures Grown by Molecular Beam Epitaxy

AlGaAs / GaAs photosensitive structures were grown by molecular beam epitaxy and photodetector de-vices were fabricated. The structures were characterized by reflection high-energy electron diffraction (RHEED), reflectance anisotropy spectroscopy (RAS) and atomic force microscopy (AFM). Spectral charac-teristics of p-i-n structures were calculated. It is shown that obtained structures have atomically smooth surface and abrupt heterointerfaces. Room-temperature I-V measurements of fabricated photodetectors showed low dark current Id=3.38 nA at reverse bias Urev=5 V. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3613

Status of “Siberia-2” SR sourse preinjector

Improvements made in linac systems have significantly increased the reliability of its operation. At present time the linac injects an electron beam with an energy of 75 MeV, beam current of 65 mA (DE/E=1%), with a pulse duration of 18 ns at a repetition rate of 1 pps