The cultural and historical context behind the formation of the architectural image of Nakhichevan-on-Don (Late 18th — Early 20th Centuries)

Submitted on 27 February, 2018. Accepted on 21 June, 2018.Поступила в редакцию 27.02.2018. Принята к печати 21.06.2018.Архитектурный образ Нахичевани-на-Дону на протяжении всего изучаемого периода (конец XVIII — начало XX в.) формировался под влиянием идей и норм русской архитектуры Нового времени, выработанных в первую очередь Санкт-Петербургской архитектурной школой. Неудивительно, что столичная архитектура оказывала влияние на формы и стилистику архитектуры малых городов. О роли Петербурга в формировании архитектурных образов провинциальных русских городов написано немало научных работ. Однако в исследованиях, посвященных Нахичевани-на-Дону, эта роль оставалась практически незамеченной. Проведение подобного исследования представляется особо интересным в связи с тем, что Нахичевань-на-Дону не являлась собственно русским городом, а основана в 1779 г. армянами, переселенными из Крыма в пределы Российской империи. Анализ культурно-исторического контекста формирования архитектуры Нахичевани-на-Дону предпринят с целью выявления культурного дуализма, нашедшего отражение в архитектуре города и проявившегося, с одной стороны, в интеграции донских армян в русское культурное пространство, а с другой стороны – в их стремлении к национальной консолидации. В статье на примерах показано обращение армян к архитектуре Санкт-Петербурга и одновременные поиски национального стиля. Данная работа основана на комплексном изучении архивных материалов, исторических свидетельств современников и натурных историко-архитектурных обследованиях памятников. Ведущими методами исследования стали сравнительный, историко-генетический и стилистический анализы архитектуры Нахичевани-на-Дону. Авторы применяли системный подход, позволяющий учитывать различные аспекты культуры донских армян, и изучать архитектуру города в контексте его культурной среды в целом.This article focuses on the study of influence of Russian architecture of the Modern Age developed mostly under the influence of the St Petersburg architectural school on the artistic and spatial organisation of Nakhichevan-on-Don. It is not surprising that the architecture of the capital had a considerable influence on the forms and style of architecture of provincial cities. There are many scholarly works on the role of St Petersburg in the formation of the architectural image of provincial Russian cities. However, the role of the architecture of the capital of the Russian Empire remained virtually unnoticed in research devoted to Nakhichevan-on-Don. Hence, it is particularly interesting to examine the city’s architecture as Nakhichevan-on-Don was not a Russian city but one founded in 1779 by the Armenians who moved from Crimea to the Russian Empire. The analysis of the cultural and historical context of the formation of Nakhichevanon-Don’s architecture aims to reveal the cultural dualism reflected in the architecture of the city and manifesting itself in the integration of the Don Armenians into the Russian cultural space on the one hand, and in their desire for national consolidation on the other hand. The work is based on a comprehensive study of archival materials, historical evidence of contemporaries, and on-site historical and architectural surveys of monuments. The leading methods of the research are comparative analysis, historical-genetic analysis, and stylistic analysis of the architecture of Nakhichevan-on-Don. The authors use a system approach which allows them to consider various aspects of the culture of the Don Armenians and study the architecture of the city in the context of its cultural environment as a whole

Carbon ion acceleration from thin foil targets irradiated by ultrahigh-contrast, ultraintense laser pulses

In this study, ion acceleration from thin planar target foils irradiated by ultrahigh-contrast (10(10)), ultrashort (50 fs) laser pulses focused to intensities of 7 x 10(20) W cm(-2) is investigated experimentally. Target normal sheath acceleration (TNSA) is found to be the dominant ion acceleration mechanism when the target thickness is >= 50 nm and laser pulses are linearly polarized. Under these conditions, irradiation at normal incidence is found to produce higher energy ions than oblique incidence at 35 degrees with respect to the target normal. Simulations using one-dimensional (1D) boosted and 2D particle-in-cell codes support the result, showing increased energy coupling efficiency to fast electrons for normal incidence. The effects of target composition and thickness on the acceleration of carbon ions are reported and compared to calculations using analytical models of ion acceleration

Hypergravity effects on glide arc plasma

The behaviour of a special type of electric discharge – the gliding arc plasma – has been investigated in hypergravity (1g –18g) using the Large Diameter Centrifuge (LDC) at ESA/ESTEC. The discharge voltage and current together with the videosignal from a fast camera have been recorded during the experiment. The gliding of the arc is governed by hot gas buoyancy and by consequence, gravity. Increasing the centrifugal acceleration makes the glide arc movement substantially faster. Whereas at 1g the discharge was stationary, at 6g it glided with 7 Hz frequency and at 18g the gliding frequency was 11 Hz. We describe a simple model for the glide arc movement assuming low gas flow velocities, which is compared to our experimental results

Search for π⁰ decays to invisible particles

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Measurement of the very rare K + → π+νν¯ decay

The NA62 experiment reports the branching ratio measurement BR(K+→π+νν¯)=(10.6−3.4+4.0|stat±0.9syst)×10−11 at 68% CL, based on the observation of 20 signal candidates with an expected background of 7.0 events from the total data sample collected at the CERN SPS during 2016–2018. This provides evidence for the very rare K+→π+νν¯ decay, observed with a significance of 3.4σ. The experiment achieves a single event sensitivity of (0.839 ± 0.054) × 10−11, corresponding to 10.0 events assuming the Standard Model branching ratio of (8.4 ± 1.0) × 10−11. This measurement is also used to set limits on BR(K+→ π+X), where X is a scalar or pseudo-scalar particle. Details are given of the analysis of the 2018 data sample, which corresponds to about 80% of the total data sample

Search for heavy neutral lepton production in K+ decays to positrons

A search for heavy neutral lepton (N) production in K+→e+N decays using the data sample collected by the NA62 experiment at CERN in 2017-2018 is reported. Upper limits of the extended neutrino mixing matrix element |Ue4|^2 are established at the level of 10^−9 over most of the accessible heavy neutral lepton mass range 144-462 MeV/c^2, with the assumption that the lifetime exceeds 50 ns. These limits improve significantly upon those of previous production and decay searches. The |Ue4|^2 range favoured by Big Bang Nucleosynthesis is excluded up to a mass of about 340 MeV/c^2

An investigation of the very rare K+ → π+ vv¯ decay

The NA62 experiment reports an investigation of the K+→π+ν ̄ν mode from a sample of K+ decays collected in 2017 at the CERN SPS. The experiment has achieved a single event sensitivity of (0.389±0.024)×10−10, corresponding to 2.2 events assuming the Standard Model branching ratio of (8.4±1.0)×10−11. Two signal candidates are observed with an expected background of 1.5 events. Combined with the result of a similar analysis conducted by NA62 on a smaller data set recorded in 2016, the collaboration now reports an upper limit of 1.78×10−10 for the K+→π+ν ̄ν branching ratio at 90% CL. This, together with the corresponding 68% CL measurement of (0.48+0.72−0.48)×10−10, are currently the most precise results worldwide, and are able to constrain some New Physics models that predict large enhancements still allowed by previous measurements

New measurement of the radiative decay Ke3g at the NA62 experiment at CERN

The NA62 experiment at CERN reports new results from the study of the radiative kaon decay K+→π0e+νγ (Ke3γ ), using a data sample recorded in 2017 and 2018. Preliminary results with the most precise measurement of the Ke3γ branching ratio, and a T-asymmetry measurement in the Ke3γ decay, are presented

Search for lepton number and flavour violation in K+ and pi0 decays

The NA62 experiment at CERN collected a large sample of charged kaon decays into final states with multiple charged particles in 2016-2018. This sample provides sensitivities to rare decays with branching ratios as low as 10 −11 . Searches for the lepton number violating K + → π − µ + e+ decay and the lepton flavour violating K + → π + µ − e + and π 0 → µ − e + decays are reported. No evidence for these decays is found and upper limits of the branching ratios are obtained at 90% confidence level. These results improve by one order of magnitude over previous results for these decay modes

Search for K+ decays to a muon and invisible particles

The NA62 experiment at CERN reports searches for K+ → μ+N and K+ → μ+νX decays, where N and X are massive invisible particles, using the 2016–2018 data set. The N particle is assumed to be a heavy neutral lepton, and the results are expressed as upper limits of O(10−8) of the neutrino mixing parameter |Uμ4|2 for N masses in the range 200–384 MeV/c2 and lifetime exceeding 50 ns. The X particle is considered a scalar or vector hidden sector mediator decaying to an invisible final state, and upper limits of the decay branching fraction for X masses in the range 10–370 MeV/c2 are reported for the first time, ranging from O(10−5) to O(10−7). An improved upper limit of 1.0×10−6 is established at 90% CL on the K+ → μ+ννν¯ branching fraction