Recent results on the properties of two-phase argon avalanche detectors

The characteristic properties of two-phase Ar avalanche detectors, including those obtained with CsI photocathode, are further studied. Such detectors are relevant in the field of coherent neutrino-nucleus scattering and dark matter search experiments. The detectors investigated comprised a 1 cm thick liquid Ar layer followed by a triple-GEM multiplier. In these detectors, typical gains reaching 10000 were obtained with good reproducibility and a stable operation for at least one day was demonstrated. Amplitude and pulse-shape characteristics are presented under irradiation with X-rays, gamma-rays and neutrons from different radioactive sources. The detection of both primary scintillation and ionization signals at higher gains, at a deposited energy of 60 keV, has been demonstrated.Comment: 6 pages, 11 figures. Presented at Xth Int. Conf. for Collid. Beam Phys., Feb 28 - March 6, 2008, Novosibirsk, to be published in Nucl. Instr. Meth.

The training of verbal creativity with students of psychological speciality

The article defines the term verbal creativity, distinguishes its criteria, sheds light on its role in teaching a foreign language to future psychologists. It also suggests stages of verbal creativity training and a set of exercises in order to facilitate the development of students' communicative competence as a component of their professional competence

Хеджи в женском речевом поведении (на примере английского, русского и украинского языков)

The article sheds light on differences in quontitative and qualitative representation of hedges used by women-representatives of English, Russian and Ukrainian speech communities. The author demonstrated main functions of hedging in female speech and worked out the classification of means of expressing hedges in female speech behaviour in English, Russian and Ukrainian languages.В статье освещаются количественные и качественные различия репрезентации хеджей в речи женщин-представительниц английского, украинского и русского языковых сообществ. Автором выделены основные функции хеджей в женской речи и разработана классификация средств выражения хеджей в женском речевом поведении в английском, украинском и русском языках.В статті висвітлюються кількісні та якісні розбіжності репрезентації хеджів в мовленні жінок-представниць англійської, російської та української мовних спільнот. Автором виділені основні функції хеджів в жіночому мовленні та розроблено класифікацію засобів вираження хеджів на матеріалі жіночої мовленнєвої поведінки в англійській, українській та російській мовах

Сравнительная характеристика разделительных вопросов в женском речевом поведении (в английском, украинском и русском языках)

The article sheds light on isomorphic and allomorphic features of tags in female speech in English, Russian and Ukrainian languages. It also demonstrates the differences in functional distribution of tag questions in contrasted languages.Стаття висвітлює ізоморфні та аломорфні риси розділових питань у жіночій мовленнєвій поведінці в англійській, українській та російській мовах. Автор також демонструє відмінності у функціональній дистрибуції розділових питань у порівнюваних мовах.Статья освещает изоморфические и алломорфические черты разделительных вопросов в женском речевом поведении в английском, украинском и русском языках. Автор также демонстрирует отличия в функциональной дистрибуции разделительных вопросов в сравниваемых яхыках

GEM operation in helium and neon at low temperatures

We study the performance of Gas Electron Multipliers (GEMs) in gaseous He, Ne and Ne+H2 at temperatures in the range of 2.6-293 K. In He, at temperatures between 62 and 293 K, the triple-GEM structures often operate at rather high gains, exceeding 1000. There is an indication that this high gain is achieved by Penning effect in the gas impurities released by outgassing. At lower temperatures the gain-voltage characteristics are significantly modified probably due to the freeze-out of impurities. In particular, the double-GEM and single-GEM structures can operate down to 2.6 K at gains reaching only several tens at a gas density of about 0.5 g/l; at higher densities the maximum gain drops further. In Ne, the maximum gain also drops at cryogenic temperatures. The gain drop in Ne at low temperatures can be reestablished in Penning mixtures of Ne+H2: very high gains, exceeding 10000, have been obtained in these mixtures at 50-60 K, at a density of 9.2 g/l corresponding to that of saturated Ne vapor near 27 K. The results obtained are relevant in the fields of two-phase He and Ne detectors for solar neutrino detection and electron avalanching at low temperatures.Comment: 13 pages, 14 figures. Accepted for publishing in Nucl. Instr. and Meth.

The use of quantum-correlated D^0 decays for phi3 measurement

We report the results of the Monte-Carlo study of the method to determine the CKM angle phi3 using Dalitz plot analysis of D0 decay from B->DK process. Our main goal is to find the optimal strategy for a model-independent phi3 extraction. We find that the analysis using decays of CP-tagged D mesons only cannot provide a completely model-independent measurement in the case of limited data sample. The procedure involving binned analysis of B->DK and psi(3770)->(K0 pi+ pi-)_D (K0 pi+ pi-)_D decays is proposed, that allows to reach the phi3 precision comparable to unbinned model-dependent fit.Comment: Replaced by journal versio

Enhancement and suppression of tunneling by controlling symmetries of a potential barrier

We present a class of 2D systems which shows a counterintuitive property that contradicts a semi classical intuition: A 2D quantum particle "prefers" tunneling through a barrier rather than traveling above it. Viewing the one particle 2D system as the system of two 1D particles, it is demonstrated that this effect occurs due to a specific symmetry of the barrier that forces excitations of the interparticle degree of freedom that, in turn, leads to the appearance of an effective potential barrier even though there is no "real" barrier. This phenomenon cannot exist in 1D.Comment: 10 pages and 7 figure