СТЕКЛОКЕРАМИЧЕСКИЕ МАТЕРИАЛЫ ДЛЯ РЕГИСТРАЦИИ НЕЙТРОНОВ

In the present article we discuss a new class of scintillation materials that are prospective for application in high energy physics experiments and for detection of neutrons in a wide energy range. Обсуждается новый класс сцинтилляционных материалов, перспективных для применения в экспериментах в физике высоких энергий и измерении нейтронов в широком диапазоне энергий.

Transient Absorption Phenomena in Synthetic HPHT and CVD Diamonds for a Fast Timing in Nuclear Instrumentation

In this study, we investigate  transient phenomena in synthetic diamonds  obtained by High Pressure High Temperature and Chemical Vapor Deposition methods. Study was aimed at searching for inorganic crystalline media combining ionizing radiation detecting properties and non-linear absorption of ultra-short laser pulses. The nonlinear pump-and-probe optical absorption technique with of 140 fs laser pulses was used to study the effects

Development of an advanced modular setup for the on beam characterization of oriented crystals

Recently, the particle physics community has put an increasing effort in developing radiation detectors and equipment based on oriented crystals. A key feature that distinguishes an oriented crystal from the ordinary matter is the reduc-tion of the radiation length (X0) seen by electrons, positrons and photons crossing the lattice along one of its symmetry axes. This effect has been experimentally ob-served only in the last few decades and with samples limited in number, composition and length. In order to characterize a variety of oriented crystals with a standardized procedure, the STORM Collaboration has developed an advanced modular setup, which allows to study the features of any crystal sample with both electron (or positron) and photon beams. This contribution describes the key elements of this setup, namely silicon strip tracking detectors, plastic scintillators, Silicon Photo -Multipliers (SiPMs) coupled to the crystal under test, a photon calorimeter and an electromagnetic spectrometer

Development of an advanced modular setup for the on beam characterization of oriented crystals

Recently, the particle physics community has put an increasing effort in developing radiation detectors and equipment based on oriented crystals. A key feature that distinguishes an oriented crystal from the ordinary matter is the reduction of the radiation length (X0) seen by electrons, positrons and photons crossing the lattice along one of its symmetry axes. This effect has been experimentally observed only in the last few decades and with samples limited in number, composition and length. In order to characterize a variety of oriented crystals with a standardized procedure, the STORM Collaboration has developed an advanced modular setup, which allows to study the features of any crystal sample with both electron (or positron) and photon beams. This contribution describes the key elements of this setup, namely silicon strip tracking detectors, plastic scintillators, Silicon Photo-Multipliers (SiPMs) coupled to the crystal under test, a photon calorimeter and an electromagnetic spectrometer

Luminescence Spectroscopy of Quaternary Garnets Doped with Trivalent Rare-Earth Ions

Spectroscopy and energy transport in multi–ion ceramics with garnet structure (GYAGG) doped with rare–earth ions (Ce3+, Tb3+, Eu3+) were studied by photoluminescence (PL), cathodoluminescence (CL) and X–ray luminescence (XRL) methods.The work was partially supported by the Ministry of Science and Higher Education of the Russian Federation (through the basic part of the government mandate, project No. FEUZ-2020-0060)

Radiation hardness qualification of PbWO4 scintillation crystals for the CMS Electromagnetic Calorimeter

This is the Pre-print version of the Article. The official published version can be accessed from the link below - Copyright @ 2010 IOPEnsuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN. The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers. The present article reviews the related scientific and technological problems encountered

Feasibility studies of time-like proton electromagnetic form factors at PANDA at FAIR

Simulation results for future measurements of electromagnetic proton form factors at \PANDA (FAIR) within the PandaRoot software framework are reported. The statistical precision with which the proton form factors can be determined is estimated. The signal channel $\bar p p \to e^+ e^-$ is studied on the basis of two different but consistent procedures. The suppression of the main background channel, $\textit{i.e.}$ $\bar p p \to \pi^+ \pi^-$, is studied. Furthermore, the background versus signal efficiency, statistical and systematical uncertainties on the extracted proton form factors are evaluated using two different procedures. The results are consistent with those of a previous simulation study using an older, simplified framework. However, a slightly better precision is achieved in the PandaRoot study in a large range of momentum transfer, assuming the nominal beam conditions and detector performance

Lanthanoid-doped quaternary garnets as phosphors for high brightness cathodoluminescence-based light sources

Gadolinium-yttrium- aluminum-gallium garnets (GYAGG) doped and codoped with Eu, Tb, and Ce were manufactured as ceramics to develop long-wavelength phosphors for high-brightness white light sources based on cathodoluminescence (CL). The CL light yield (LY) of Tb-doped ceramics at high-intensity electron beam excitation is shown to be more than twice as high as that of the conventional phosphor YAG:Ce, whereas codoping with Eu to redshift the chromaticity results in reducing the LY approximately to the level of YAG:Ce. The LY might be substantially improved by using a mix of Tb- and Eu-doped GYGAG powders instead of a single codoped GYGAG to produce ceramic phosphor. The high LY is explained by favorable contribution of Gd sublattice in excitation transfer to activator ions. Chromaticity of phosphors GYGAG:Tb, Eu can be tuned in a wide range by varying the ratio of Tb to Eu concentration. They are radiation resistant and stabile in the temperature range from 300 to 450 K. © 2022 The Author(s)Ministry of Education and Science of the Russian Federation, Minobrnauka: 075-11-2021-070, 075-15-2021-1353, FEUZ-2020-0060This work was supported by the Ministry of Science and Higher Education of the Russian Federation (FEUZ-2020-0060, No. 075-15-2021-1353 & 075-11-2021-070)

ИСПОЛЬЗОВАНИЕ ДВУХФОТОННОГО ПОГЛОЩЕНИЯ В НЕОРГАНИЧЕСКИХ СЦИНТИЛЛЯЦИОННЫХ МАТЕРИАЛАХ ДЛЯ ФОРМИРОВАНИЯ СУБПИКОСЕКУНДНЫХ ВРЕМЕННЫХ МЕТОК ВЗАИМОДЕЙСТВИЯ С ИОНИЗИРУЮЩИМ ИЗЛУЧЕНИЕМ

The features of the two-photon absorption signal in lead tungstate crystals (PbWO4) in the “pump – probe” experiment are considered. The differences in the spectral dependences of the recorded two-photon absorption effect in the presence of ionizing radiation of a crystal and without it are discovered. The method of utilizing the effect to generate a time stamp of interaction of ionizing radiation with a scintillator is proposed. Рассмотрены особенности сигнала двухфотонного поглощения в кристалле вольфрамата свинца (PbWO4) в эксперименте типа «накачка – зондирование». Обнаружены различия в спектральных зависимостях регистрируемого эффекта двухфотонного поглощения при наличии ионизирующего облучения кристалла и без него. Предложен метод использования эффекта для формирования временной метки взаимодействия ионизирующего излучения с сцинтиллятором.

ДИНАМИКА СВОБОДНЫХ НОСИТЕЛЕЙ В ТЯЖЕЛЫХ СКИНТИЛЯЦИОННЫХ МАТЕРИАЛАХ СО СТРУКТУРОЙ ГРАНАТА

Ce-doped Lu3 Al5 O12 (LuAG), and Gd3 Al2 Ga3 O12 (GAGG) crystals with and without codoping by Mg2+ ions have been studied by the nonlinear absorption spectroscopy method. A faster rise time of transient optical absorption has been observed in all crystals codoped with Mg in comparison to Mg-free samples. A significant difference in the time evolution of the differential optical density in GAGG in comparison to LuAG crystals is revealed. in gadolinium garnets an absorption band peaked in the blue-green range and decaying with characteristic time of ~2 ps is observed. This band is considered to be due to absorption of free electrons before their trapping by Ce3+doping ions. A broad transient absorption band in the yellowred region is attributed to absorption from the Ce3+ excited states. Легированные ионами Се кристаллы Lu3 Al5 O12 (LuAG) и Gd3 Al2 Ga3 O12 (GAGG) с и без кодопирования ионами Mg2+ исследованы методом нелинейной абсорбционной спектроскопии. Ускорение времени нарастания переходного оптического поглощения наблюдалось в кристаллах, кодопированных ионами Mg, по сравнению с образцами без Mg. Выявлено существенное различие во временной эволюции дифференциальной оптической плотности в GAGG в сравнении с кристаллом LuAG. В гадолиниевых гранатах наблюдается полоса поглощения в сине- зеленом диапазоне с затуханием с характерным временем ~2 пс. Эта полоса соотнесена поглощению свободными электронами до их захвата примесными ионами Ce3+. Широкая полоса переходного поглощения в желто-красной области обусловлена поглощением из возбужденных состояний ионов Ce3+.