Study of Characteristics of the Quasi-spherical Measurement Modules of the Cherenkov Water Calorimeter NEVOD

AbstractThe use of quasi-spherical modules with several PMTs with flat photocathodes in Cherenkov water detectors is discussed. Properties of the response of such modules are examined. The characteristics of the quasi-spherical module with six PMTs that is used in the Cherenkov water calorimeter NEVOD are considered. The results of studying the isotropy of the amplitude response of this module and the quality of reconstruction of light direction with a single module and with a group of modules are demonstrated

Statistique mensuelle de la viande. 1968 N° 4 APRIL-AVRIL = Monthly statistiques of meat. 1968 No. 4 April

In high energy experiments such as active beam dump searches for rare decays and missing energy events, the beam purity is a crucial parameter. In this paper we present a technique to reject heavy charged particle contamination in the 100 GeV electron beam of the H4 beam line at CERN SPS. The method is based on the detection with BGO scintillators of the synchrotron radiation emitted by the electrons passing through a bending dipole magnet. A 100 GeV pi- beam is used to test the method in the NA64 experiment resulting in a suppression factor of 10−5 while the efficiency for electron detection is 95%. The spectra and the rejection factors are in very good agreement with the Monte Carlo simulation. The reported suppression factors are significantly better than previously achieved.ISSN:0168-9002ISSN:1872-957

Typical emergencies and estimation risk of their rise on flak antiaircraft complex C-300П

Формулюються типові нештатні ситуації, яки виникають внаслідок некерованого руху зенітних керованих ракет із-за можливих відмов в бортовый або в наземної апаратурі при стрільбах ЗРК С-300П, та що необхідні при розрахунках зон небезпеки. Наводяться формули для розрахунку ризиків (імовірностей) виникнення нештатних ситуацій.Формулируются типовые нештатные ситуации, которые возникают вследствие неуправляемого движения зенитных управляемых ракет из-за возможных отказов в бортовой или наземной аппаратуре при стрельбах ЗРК С-300П, и которые необходимы при расчетах зоны опасности. Приводятся формулы для расчетов рисков (вероятностей) возникновения нештатных ситуаций.Typical emergencies which rise as a result of noncontrol move of antiaircraft missile due to possible failure on-board or ground-based apparatus on flak antiaircraft complex С-300П and necessary for computation peril zone are formulated. Formulas for computation risk (probability) rise on emergencies are given

MEASURING OF GROUP TARGETS GEOMETRICAL SIZES BY MONOIMPULSE ACCOMPANIMENT RADAR

На основі аналізу сигналів в приймальних каналах моноімпульсного пеленгатора РЛС супроводження запропонований метод вимірювання кутових розмірів групової цілі в горизонтальній та вертикальній площинах, та перетворення їх у геометричні розмірі, що дозволяє відрізняти групову ціль від одиночної та тим самим забезпечувати бойову обслугу ЗРК достовірною інформацією про складність цілі, що підлягає обстрілу.На основе анализа сигналов в приемных каналах моноимпульсного пеленгатора РЛС сопровождение предложен метод измерения угловых размеров групповой цели в горизонтальной и вертикальной плоскостях, и превращение их в геометрических размере, что позволяет отличать групповую цель от одиночной и тем самым обеспечивать боевое обслуживание ЗРК достоверной информацией о сложности цели, которая подлежит обстрелу.On the basis of analysis of signals in the receiving channels of monoimpulse accompaniment radar the offered method of measuring of angular sizes of group purpose in horizontal and vertical planes, and converting of them into geometrical size, that allows to distinguish a group purpose from single and to provide battle service of ЗРК by reliable information about complication of target, which is subject to the fire

Confinement of discrete breathers in inhomogeneously profiled nonlinear chains

We investigate numerically the scattering of a moving discrete breather on a pair of junctions in a Fermi-Pasta-Ulam chain. These junctions delimit an extended region with different masses of the particles. We consider (i) a rectangular trap, (ii) a wedge shaped trap, and (iii) a smoothly varying convex or concave mass profile. All three cases lead to DB confinement, with the ease of trapping depending on the profile of the trap. We also study the collision and trapping of two DBs within the profile as a function of trap width, shape, and approach time at the two junctions. The latter controls whether one or both DBs are trapped

Performance of Multiplexed XY Resistive Micromegas detectors in a high intensity beam

We present the performance of multiplexed XY resistive Micromegas detectors tested in the CERN SPS 100 GeV/c electron beam at intensities up to 3.3×105e−∕(s⋅cm2) . So far, all studies with multiplexed Micromegas have only been reported for tests with radioactive sources and cosmic rays. The use of multiplexed modules in high intensity environments was not explored due to the effect of ambiguities in the reconstruction of the hit point caused by the multiplexing feature. For the specific mapping and beam intensities analyzed in this work with a multiplexing factor of five, more than 50% level of ambiguity is introduced due to particle pile-up as well as fake clusters due to the mapping feature. Our results prove that by using the additional information of cluster size and integrated charge from the signal clusters induced on the XY strips, the ambiguities can be reduced to a level below 2%. The tested detectors are used in the CERN NA64 experiment for tracking the incoming particles bending in a magnetic field in order to reconstruct their momentum. The average hit detection efficiency of each module was found to be ∼ 96% at the highest beam intensities. By using four modules a tracking resolution of 1.1% was obtained with ∼ 85% combined tracking efficiency.We present the performance of multiplexed XY resistive Micromegas detectors tested in the CERN SPS 100 GeV/c electron beam at intensities up to 3.3 $\times$ 10$^5$ e$^-$/(s$\cdot$cm$^2$). So far, all studies with multiplexed Micromegas have only been reported for tests with radioactive sources and cosmic rays. The use of multiplexed modules in high intensity environments was not explored due to the effect of ambiguities in the reconstruction of the hit point caused by the multiplexing feature. At the beam intensities analysed in this work and with a multiplexing factor of 5, more than 50% level of ambiguity is introduced. Our results prove that by using the additional information of cluster size and integrated charge from the signal clusters induced on the XY strips, the ambiguities can be reduced to a level below 2%. The tested detectors are used in the CERN NA64 experiment for tracking the incoming particles bending in a magnetic field in order to reconstruct their momentum. The average hit detection efficiency of each module was found to be $\sim$ 96% at the highest beam intensities. By using four modules a tracking resolution of 1.1% was obtained with $\sim$ 85% combined tracking efficiency

Performance of Multiplexed XY Resistive Micromegas detectors in a high intensity beam

We present the performance of multiplexed XY resistive Micromegas detectors tested in the CERN SPS 100 GeV/c electron beam at intensities up to 3.3 × 10 5e−/(s-cm2). So far, all studies with multiplexed Micromegas have only been reported for tests with radioactive sources and cosmic rays. The use of multiplexed modules in high intensity environments was not explored due to the effect of ambiguities in the reconstruction of the hit point caused by the multiplexing feature. For the specific mapping and beam intensities analyzed in this work with a multiplexing factor of five, more than 50% level of ambiguity is introduced due to particle pile-up as well as fake clusters due to the mapping feature. Our results prove that by using the additional information of cluster size and integrated charge from the signal clusters induced on the XY strips, the ambiguities can be reduced to a level below 2%. The tested detectors are used in the CERN NA64 experiment for tracking the incoming particles bending in a magnetic field in order to reconstruct their momentum. The average hit detection efficiency of each module was found to be 96% at the highest beam intensities. By using four modules a tracking resolution of 1.1% was obtained with 85% combined tracking efficiency.ISSN:0168-9002ISSN:1872-957