Enhancing the energy resolution of resonant coherent excitation using the cooled U 89+ beam extracted from the ESR

Synopsis We report on the resonant coherent excitation (RCE) of the 2 s -2 p 3/2 transition in Li-like U 89+ with an enhanced energy resolution, which was achieved by reducing the projectiles momentum spread. The kinetic temperature of the beam was decreased by electron cooling in the ESR, and the collisional momentum broadening in the target was suppressed by the use of thin crystal (1.0 and 2.5 μm-thick). The resonance width was observed to be ∼1.4 eV in FWHM, which is three-times narrower than that from the previous work

Structure and morphology of low mechanical loss TiO₂-doped Ta₂O₅

The exceptional stability required from high finesse optical cavities and high precision interferometers is fundamentally limited by Brownian motion noise in the interference coatings of the cavity mirrors. In amorphous oxide coatings these thermally driven fluctuations are dominant in the high index layer compared to those in the low index SiO₂ layer in the stack. We present a systematic study of the evolution of the structural and optical properties of ion beam sputtered TiO₂-doped Ta₂O₅ films with annealing temperature. We show that low mechanical loss in TiO₂-doped Ta₂O₅ with a Ti cation ratio = 0.27 is associated with a material that consists of a homogeneous titanium-tantalum-oxygen mixture containing a low density of nanometer sized Ar-filled voids. When the Ti cation ratio is 0.53, phase separation occurs leading to increased mechanical loss. These results suggest that amorphous mixed oxides with low mechanical loss could be identified by considering the thermodynamics of ternary phase formation

Structure and morphology of low mechanical loss TiO₂-doped Ta₂O₅

The exceptional stability required from high finesse optical cavities and high precision interferometers is fundamentally limited by Brownian motion noise in the interference coatings of the cavity mirrors. In amorphous oxide coatings these thermally driven fluctuations are dominant in the high index layer compared to those in the low index SiO₂ layer in the stack. We present a systematic study of the evolution of the structural and optical properties of ion beam sputtered TiO₂-doped Ta₂O₅ films with annealing temperature. We show that low mechanical loss in TiO₂-doped Ta₂O₅ with a Ti cation ratio = 0.27 is associated with a material that consists of a homogeneous titanium-tantalum-oxygen mixture containing a low density of nanometer sized Ar-filled voids. When the Ti cation ratio is 0.53, phase separation occurs leading to increased mechanical loss. These results suggest that amorphous mixed oxides with low mechanical loss could be identified by considering the thermodynamics of ternary phase formation

Approaching the motional ground state of a 10-kg object

The motion of a mechanical object— even a human-sized object— should be governed by the rules of quantum mechanics. Coaxing them into a quantum state is, however, difficult: the thermal environment effectively masks any quantum signature of the object’s motion. Indeed, it also masks effects of proposed modifications of quantum mechanics at large mass scales. We prepare the center-of-mass motion of a 10 kg mechanical oscillator in a state with an average phonon occupation of 10.8. The reduction in oscillator temperature, from room temperature to 77 nK, represents a 100-fold improvement in the reduction of temperature of a solid-state mechanical oscillator— commensurate with a 11 orders-of-magnitude suppression of quantum back-action by feedback — and a 10 orders-of-magnitude increase in the mass of an object prepared close to its motional ground state

Point absorbers in Advanced LIGO

Small, highly absorbing points are randomly present on the surfaces of the main interferometer optics in Advanced LIGO. The resulting nanometer scale thermo-elastic deformations and substrate lenses from these micronscale absorbers significantly reduce the sensitivity of the interferometer directly though a reduction in the power-recycling gain and indirect interactions with the feedback control system. We review the expected surface deformation from point absorbers and provide a pedagogical description of the impact on power buildup in second generation gravitational wave detectors (dual-recycled Fabry-Perot Michelson interferometers). This analysis predicts that the power-dependent reduction in interferometer performance will significantly degrade maximum stored power by up to 50% and, hence, limit GW sensitivity, but it suggests system wide corrections that can be implemented in current and future GW detectors. This is particularly pressing given that future GW detectors call for an order of magnitude more stored power than currently used in Advanced LIGO in Observing Run 3. We briefly review strategies to mitigate the effects of point absorbers in current and future GW wave detectors to maximize the success of these enterprises. (C) 2021 Optical Society of America

The level of stress regulation in psychologist students of different years of education

This article presents the results of a study of the level of stress regulation in students of different years of education majoring in Clinical Psychology. First, second and fourth year students have been comparedВ данной статье представлены результаты исследования уровня стрессовой регуляции у студентов разных курсов специальности «Клиническая психология». Сравниваются студенты первого, второго и четвертого курсо

Практика применения и особенности контроля олигосахаридов в производстве продуктов специализированного питания. Обзор

Functional oligosaccharides include various  groups  of carbohydrates with  the  biological activity — an  ability  to modulate gut microbiota due to the  prebiotic, anti-adhesive and anti-inflammatory activities. The unique properties of oligosaccharides explain a wide spectrum of their use in the dairy industry: from food ingredients for imitation  of the  prebiotic activity of human milk oligosaccharides in infant dry milk mixtures to structuring additives, replacers of sugar and fat. When choosing oligosaccharides for inclusion into dairy products, their biological activity and technological properties that depend on a source  and method for extraction of these compounds are assessed. Fructooligosaccharides, galactooligosaccharides, xylooligosaccharides and pectic  oligosaccharides have been  most widely used. When developing recipes of products with stated biological effectiveness, it is necessary to remember that consumption of large  amounts of substances with prebiotic properties can lead to the  gastrointestinal disorder, which requires introducing into  practice the control of the oligosaccharide quantitative content in the product composition. The aim of this  review is analysis of possibilities of using  oligosaccharides in production of specialized  milk-based food products and  methods for controlling quality, safety  and  effectiveness of inclusion of such products into  a diet. The review considers the  existing methods for quantitative identification of oligosaccharides included in the composition of dairy products as functional ingredients. The emphasis is made on the limitations of the introduction of the developed analytical methods into  routine practice of the oligosaccharide control, which is linked with the complexity and multicomponent nature of the food matrix under study. The necessity of the further improvement of methods for quantitative identification of functional oligosaccharides in foods is shown.К функциональным олигосахаридам относятся различные группы углеводов, обладающих биологической активностью — способностью модулировать кишечную микробиоту за  счет  пребиотического, антиадгезивного и  противовоспалительного  действий.  Уникальными  свойствами  олигосахаридов  объясняется широкий спектр их применения в молочной промышленности: от пищевых ингредиентов для имитации пребиотической активности олигосахаридов грудного молока в детских сухих молочных смесях  до структурирующих добавок, заменителей сахара  и жира.  При выборе олигосахаридов для  включения в молочные  продукты оценивают их биологическую активность и технологические свойства, которые зависят от источника и способа выделения этих  соединений. Наибольшее распространение получили фруктоолигосахариды, галактоолигосахариды, ксилоолигосахариды и олигосахариды пектинового ряда. Разрабатывая рецептуры продуктов с заявленной биологической эффективностью, нельзя забывать, что  потребление больших количеств веществ, обладающих пребиотическими  свойствами, может  привести к нарушениям работы желудочно-кишечного тракта, что требует внедрения в практику контроля количественного содержания  олигосахаридов в составе продуктов. Целью  данного обзора является анализ возможностей применения олигосахаридов в производстве специализированных продуктов питания на  молочной основе и методов контроля качества, безопасности, эффективности включения в рацион питания такой  продукции.  В обзоре рассматриваются существующие методы количественной идентификации олигосахаридов, включаемых в состав  молочных продуктов в качестве функциональных ингредиентов. Внимание акцентируется на  ограничениях внедрения разработанных аналитических методов анализа в повседневную практику контроля олигосахаридов, что  связано со сложностью и многокомпонентностью исследуемых пищевых матриц. Показана необходимость дальнейшего совершенствования методов количественной идентификации функциональных олигосахаридов в пищевых продуктах

A high throughput instrument to measure mechanical losses in thin film coatings

Brownian thermal noise generated by mechanical losses in thin film coatings limits the sensitivity of gravitational wave detectors, as well as several high precision metrology experiments. Improving the sensitivity of the next generation of gravitational wave detectors will require optical coatings with significantly reduced mechanical losses. In this paper, we describe a system that we developed to measure the mechanical loss angle of thin film coatings deposited on fused silica substrates. The novelty of this system resides in the capability of parallel measurement of up to four samples and the ability to simultaneously probe all the resonant modes of each sample. This high throughput measurement system allows the exploration of a large number of deposition and material parameters, which can be tuned to achieve low loss coatings

Sensitivity and performance of the Advanced LIGO detectors in the third observing run

On April 1st, 2019, the Advanced Laser Interferometer Gravitational-Wave Observatory (aLIGO), joined by the Advanced Virgo detector, began the third observing run, a year-long dedicated search for gravitational radiation. The LIGO detectors have achieved a higher duty cycle and greater sensitivity to gravitational waves than ever before, with LIGO Hanford achieving angle-averaged sensitivity to binary neutron star coalescences to a distance of 111 Mpc, and LIGO Livingston to 134 Mpc with duty factors of 74.6% and 77.0% respectively. The improvement in sensitivity and stability is a result of several upgrades to the detectors, including doubled intracavity power, the addition of an in-vacuum optical parametric oscillator for squeezed-light injection, replacement of core optics and end reaction masses, and installation of acoustic mode dampers. This paper explores the purposes behind these upgrades, and explains to the best of our knowledge the noise currently limiting the sensitivity of each detector. © 2020 authors. Published by the American Physical Society