Pulse shaping system for INR proton linac

The system for proton beam pulse shaping in the 400 keV injection line of the INR linac is developed, built and implemented. The use of a traveling wave fast deflector and the Behlke Electronic fast HV transistor switch with operation voltage up to 6 kV enables formation and adjustment of different macro- and micro-pulses of the accelerated beam thus expanding considerably accelerator possibilities. It is important for many accelerator applications, especially for time-of-flight neutron studies.Реализована система формирования импульсов протонного пучка с энергией 400 кэВ на канале инжекции ускорителя ИЯИ РАН. Эта система с использованием быстрого дефлектора на бегущей волне и быстрого высоковольтного полупроводникового ключа фирмы Behlke Electronic с рабочим напряжением до 6 кВ существенно расширяет возможности ускорителя, так как обеспечивает регулирование частоты следования макроимпульсов, а также формирование различных микроимпульсов пучка. Реализация этих режимов необходима для проведения различных физических экспериментов, в том числе для времяпролетных исследований на нейтронных источниках.Реалізовано систему формування імпульсів протонного пучку з енергією 400 кеВ на каналі інжекції прискорювача ІЯД РАН. Ця система з використанням швидкого дефлектора на хвилі, що біжить, і швидкого високовольтного напівпровідникового ключа фірми Behlke Electronіc з робочою напругою до 6 кВ істотно розширює можливості прискорювача, тому що забезпечує регулювання частоти проходження макроімпульсів, а також формування різних мікроімпульсів пучка. Реалізація цих режимів необхідна для проведення різних фізичних експериментів, у тому числі для часопролітних досліджень на нейтронних джерелах

The COMPASS Experiment at CERN

The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.Comment: 84 papes, 74 figure

The Deuteron Spin-dependent Structure Function g1d and its First Moment

We present a measurement of the deuteron spin-dependent structure function g1d based on the data collected by the COMPASS experiment at CERN during the years 2002-2004. The data provide an accurate evaluation for Gamma_1^d, the first moment of g1d(x), and for the matrix element of the singlet axial current, a0. The results of QCD fits in the next to leading order (NLO) on all g1 deep inelastic scattering data are also presented. They provide two solutions with the gluon spin distribution function Delta G positive or negative, which describe the data equally well. In both cases, at Q^2 = 3 (GeV/c)^2 the first moment of Delta G is found to be of the order of 0.2 - 0.3 in absolute value.Comment: fits redone using MRST2004 instead of MRSV1998 for G(x), correlation matrix adde

A new measurement of the Collins and Sivers asymmetries on a transversely polarised deuteron target

New high precision measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarised 6LiD target are presented. The data were taken in 2003 and 2004 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. Both the Collins and Sivers asymmetries turn out to be compatible with zero, within the present statistical errors, which are more than a factor of 2 smaller than those of the published COMPASS results from the 2002 data. The final results from the 2002, 2003 and 2004 runs are compared with naive expectations and with existing model calculations.Comment: 40 pages, 28 figure

Collins and Sivers asymmetries for pions and kaons in muon-deuteron DIS

The measurements of the Collins and Sivers asymmetries of identified hadrons produced in deep-inelastic scattering of 160 GeV/c muons on a transversely polarised 6LiD target at COMPASS are presented. The results for charged pions and charged and neutral kaons correspond to all data available, which were collected from 2002 to 2004. For all final state particles both the Collins and Sivers asymmetries turn out to be small, compatible with zero within the statistical errors, in line with the previously published results for not identified charged hadrons, and with the expected cancellation between the u- and d-quark contributions.Comment: 16 pages, 9 figures, added author Efremov, calculated pure kaon asymmetries instead of those for experimental kaon/pion mixture (mainly error affected

Double spin asymmetry in exclusive rho^0 muoproduction at COMPASS

The longitudinal double spin asymmetry A_1^rho for exclusive leptoproduction of rho^0 mesons, mu + N -> mu + N + rho, is studied using the COMPASS 2002 and 2003 data. The measured reaction is incoherent exclusive rho^0 production on polarised deuterons. The Q^2 and x dependence of A_1^rho is presented in a wide kinematical range: 3x10^-3 < Q^2 < 7 (GeV/c)^2 and 5x10^-5 < x < 0.05. The presented results are the first measurements of A_1^rho at small Q2 (Q2 < 0.1 (GeV/c)^2) and small x (x < 3x10^-3). The asymmetry is in general compatible with zero in the whole kinematical range.Comment: 6 Figures, 15 pages, version 2 with updated author list, technical latex problem fixe

Recent advances in the synthesis of bioactive quinoline-based 1,2,3-triazoles via cu-catalyzed huisgen 1,3-dipolar cycloaddition (“click reaction”)

Background: Quinoline and 1,2,3-triazoles have attracted increasing attention due to their significant biological activities. Combination of these two scaffolds in one single molecule, quinolinebased 1,2,3-triazoles, gives an excellent opportunity to create new structurally diverse drug-like molecules with potent biological properties. Synthesis of these molecular hybrids has become available from a recently developed copper-catalyzed azide-alkyne cycloaddition methodology. Objective: The aim of the present review is to summarize the recent developments in Cu-catalyzed azide- alkyne cycloaddition reactions for the synthesis of functionalized quinoline-based 1,2,3-triazoles. Method: The discussion was organized according to structural criteria and functional role of the triazole ring connected to quinoline derivatives. The quinoline-based 1,2,3-triazoles obtained through azidealkyne cycloaddition methodology were classified in two general groups: quinoline-based triazoles, in which 1,2,3-triazole ring acts as pharmacophore and triazoles containing quinoline and other heterocycles, in which 1,2,3-triazole ring acts as linker. Both of these groups are based on triazole structures of type 1 (1-(quinolinyl)-1,2,3-triazoles) and type 2 (4-(quinolinyl)-1,2,3-triazoles). Results: Recent studies (112 references) on the functionalization of quinoline derivatives by 1,2,3- triazole incorporation have been discussed providing reaction conditions of organoazides and alkyne derivatives and biological activity of the obtained quinoline-based 1,2,3-triazoles. Additionally, various recent advancements in the synthetic aspects of the copper-catalyzed azide-alkyne cycloaddition have been briefly analyzed. Conclusion: This information should furnish a fresh insight for organic chemists in the design of novel bioactive molecules that contain the triazole and quinoline skeletons. It can be expected that efficient, original preparative methods for new biological materials based on quinoline-triazole structures will be reported in the near future. © 2016 Bentham Science Publishers

An efficient synthesis of new C-2 aryl substituted quinolines based on three component imino Diels-Alder reaction

Astudillo, L. Instituto de Química de Recursos Naturales, Universidad de Talca, Casilla: 747, Talca, Chile.New effective approach to the synthesis of a wide variety of C-2 nitro or aminophenyl substituted quinolines was reported using diverse intermediate 4-(2-oxopyrrolinidyl-1)-tetrahydroquinolines that were prepared by a three component imino Diels-Alder reaction was reported. The key aromatisation process occurs cleanly with the loss of the 2-oxopyrrolinidyl-1 fragment

An efficient synthesis of isoindolo[2,1-a]quinoline derivatives via imino Diels-Alder and intramolecular Diels-Alder reactions with furan

The straightforward synthesis of new isoindolo[2,1-a]quinoline derivatives from 2,4-disubstituted 1,2,3,4-tetrahydroquinolines bearing a furan fragment via the intramolecular Diels-Alder reaction is reported. The synthesis of key precursors was realized with excellent levels of diastereoselectivity either by Povarov reaction or by a multicomponent condensation approach. © Georg Thieme Verlag Stuttgart