Status of NSLS-II booster

The National Synchrotron Light Source II is a third generation light source under construction at Brookhaven National Laboratory. The project includes a highly optimized 3 GeV electron storage ring, linac pre-injector and full-energy booster-synchrotron. Budker Institute of Nuclear Physics builds booster for NSLS-II. The booster should accelerate the electron beam continuously and reliably from minimal 170 MeV injection energy to maximal energy of 3.15 GeV and average beam current of 20 mA. The booster shall be capable of multi-bunch and single bunch operation. This paper summarizes the status of NSLS-II booster.Национальный источник синхротронного излучения II является синхротроном третьего поколения, созданным в Брукхевенской национальной лаборатории. Проект включает: высокооптимизированное накопительное кольцо на 3 ГэВ, линейный ускоритель и бустерный синхротрон на полную энергию. Институт ядерной физики им. Г.И. Будкера создает бустер для NSLS-II. Бустер должен надежно и непрерывно ускорять пучок электронов от минимальной энергии инжекции 170 МэВ до максимальной энергии 3,15 ГэВ с током пучка 20 мА. Бустер должен быть способен работать в односгустковом и многосгустковом режимах. Эта статья суммирует состояние дел по бустеру для NSLS-II.Національне джерело синхротронного випромінювання II є синхротроном третього покоління, створеним у Брукхевенській національній лабораторії. Проект включає: високооптимізоване накопичувальне кільце на 3 ГеВ, лінійний прискорювач і бустерний синхротрон на повну енергію. Інститут ядерної фізики ім. Г.І. Будкера створює бустер для NSLS-II. Бустер повинен надійно і безперервно прискорювати пучок електронів від мінімальної енергії інжекції 170 МеВ до максимальної енергії 3,15 ГеВ зі струмом пучка 20 мА. Бустер повинен бути здатний працювати в односгустковому і багатосгустковому режимах. Ця стаття підсумовує стан справ по бустеру для NSLS-II

Molecular dynamics simulation of high velocity deposition of metal nanoclusters

In the present study molecular dynamics simulations were performed for collisions of nanoclusters with the substrate for determining the mechanism of formation of bound states depending on the cluster size, impact velocity and angle of incidence. A highly efficient parallel code for three-dimensional molecular dynamics was developed

Planar and Ferroelectric Antennas: Perspectives of Use in Space Industry

This paper is devoted to the new technologies of antenna system miniaturization and those technology implementation in space telecommunication and Earth remote sensing systems - for spacecraft, ground terminals and stations. Nowadays, an ability to transmit data bulks, generated by onboard equipment, becomes one of the essential performance of satellite system specifications. The conventional ways to solve the said problem result in increase of the weight and sizes of an antenna system, increase of the requirements to a power supply system, decrease of the width of antenna pattern, etc. The backlog in the technology of planar (flat) phased antenna arrays is a good basis for development of small-sized antenna systems. The authors managed to avoid a series of conventional disadvantages of the planar phased antenna arrays. The small-sized ferroelectric antennas technology is among advanced directions of antenna system development. The weight and sizes of ferroelectric antennas are smaller than those of the conventional ones in some an order of magnitude. This technology implementation in spaceborne planar phased antenna arrays would rise their efficiency. The possible applications of both planar and ferroelectric antennas in onboard and ground systems of space information transmitting/receiving have been considered

Investigations of the Dynamic Strength Variations in Metals

A line-imaging laser Doppler velocimeter has been employed to investigate the uniformity of strength properties of materials at load duration of ≈10-7 sec or less. The shock load puises were generated by a pulsed high-power proton beam facility. More or less noticeable spatial variations of the spall strength were found in such different materials as coarse-grain cast magnesium and molybdenum single crystals. In the case of magnesium, the variations of the tensile strength are governed by grain boundaries. In the single crystals, small reductions of the spall strength were accompanied by a decreasing acceleration of the fracture process.Un vélocimetre laser à résolution spatiale monodimensionelle a été utilisé pour l'étude des variations locales des propriétés mécaniques des matériaux auxquels sont appliquées des charges d'une durée de 10-7 s ou moins. Les charges impulsives sont générées par un faisceau de protons puisé à haute puissance. Des différences plus ou moins notables de la résistance mécanique ont été constatées sur des échantillons aussi différents que du magnésium moulé à gros grains et du molybdène monocristallin. Dans le cas du magnésium, les variations de la résistance sont gouvernées par les joints de grains. Dans les monocristaux, de petites réductions de la résistance furent accompagnées d'une évolution initiale des fractures plus lente