From Coulomb excitation cross sections to non-resonant astrophysical rates in three-body systems: 17^{17}Ne case

Coulomb and nuclear dissociation of $^{17}$Ne on light and heavy targets are studied theoretically. The dipole E1 strength function is determined in a broad energy range including energies of astrophysical interest. Dependence of the strength function on different parameters of the $^{17}$Ne ground state structure and continuum dynamics is analyzed in a three-body model. The discovered dependence plays an important role for studies of the strength functions for the three-body E1 dissociation and radiative capture. The constraints on the $[s^2]/[d^2]$ configuration mixing in $^{17}$Ne and on $p$-wave interaction in the $^{15}$O+$p$ channel are imposed based on experimental data for $^{17}$Ne Coulomb dissociation on heavy target.Comment: 12 pages, 13 figure

Calorimetry of the Inverse Ω→Α Phase Transformation in Zircony and Titanium

В работе с использованием метода дифференциальной сканирующей калориметрии было установлено, что в титане обратное фазовое превращение ω→α реализуется при более низких температурах и в более узком температурном интервале, чем в цирконии, независимо от величины предварительной деформации. Выявлено, что температура .>. превращения и величина выделившейся тепловой энергии в обоих металлах стабилизируются с увеличением степени деформации.In this work, using the method of differential scanning calorimetry, it was found that the reverse phase transformation ω → α in titanium occurs at lower temperatures and in a narrower temperature range than in zirconium, regardless of the amount of preliminary deformation. It was found that the transformation temperature ω → α and the value of the released thermal energy in both metals stabilize with an increase in the degree of deformationРабота выполнена в рамках государственного задания по теме «Структура» (№ АААА-А18-118020190116-6).The work was carried out within the framework of the state task on the topic “Structure” (no. AAAAA‑A18‑118020190116‑6)

INVESTIGATION OF STABILITY OF METASTABLE ω-PHASE IN PSEUDO-SINGLE CRYSTAL ZIRCONIUM FORMED DURING WARM DEFORMATION

The use of alloys of zirconium and titanium in nuclear energy and the space industry places high demands on the properties of these materials. It is known that the metastable baric ω-phase, which is formed in these materials under intense exposure, has increased hardness and brittleness. In this regard, there is a need for a detailed study of the stability of the metastable ω-phase.Использование сплавов циркония и титана в атомной энергетике, космической индустрии предъявляет к свойствам данных материалов повышенные требования. Известно, что метастабильная барическая ω-фаза, образующаяся в этих материалах при интенсивном воздействии, обладает повышенной твердостью и хрупкостью. В связи с этим возникает необходимость подробного исследования устойчивости метастабильной ω-фазы.Работа выполнена в рамках государственного задания по теме «Структура» (№ АААА-А18-118020190116-6)

Three-body correlations in direct reactions: Example of 6^{6}Be populated in (p,n)(p,n) reaction

The $^{6}$Be continuum states were populated in the charge-exchange reaction $^1$H($^{6}$Li,$^{6}$Be)$n$ collecting very high statistics data ($\sim 5 \times 10^6$ events) on the three-body $\alpha$+$p$+$p$ correlations. The $^{6}$Be excitation energy region below $\sim 3$ MeV is considered, where the data are dominated by contributions from the $0^+$ and $2^+$ states. It is demonstrated how the high-statistics few-body correlation data can be used to extract detailed information on the reaction mechanism. Such a derivation is based on the fact that highly spin-aligned states are typically populated in the direct reactions.Comment: submitted to Physical Review

The observation of long-range three-body Coloumb effects in the decay of 16Ne

The interaction of an $E/A$=57.6-MeV $^{17}$Ne beam with a Be target was used to populate levels in $^{16}$Ne following neutron knockout reactions. The decay of $^{16}$Ne states into the three-body $^{14}$O+$p$+$p$ continuum was observed in the High Resolution Array (HiRA). For the first time for a 2p emitter, correlations between the momenta of the three decay products were measured with sufficient resolution and statistics to allow for an unambiguous demonstration of their dependence on the long-range nature of the Coulomb interaction. Contrary to previous experiments, the intrinsic decay width of the $^{16}$Ne ground state was found to be narrow ($\Gamma<60$~keV), consistent with theoretical estimates.Comment: 6 pages, 5 figure

10He low-lying states structure uncovered by correlations

The 0+ ground state of the 10He nucleus produced in the 3H(8He,p)10He reaction was found at about $2.1\pm0.2$ MeV (\Gamma ~ 2 MeV) above the three-body 8He+n+n breakup threshold. Angular correlations observed for 10He decay products show prominent interference patterns allowing to draw conclusions about the structure of low-energy excited states. We interpret the observed correlations as a coherent superposition of the broad 1- state having a maximum at energy 4-6 MeV and the 2+ state above 6 MeV, setting both on top of the 0+ state "tail". This anomalous level ordering indicates that the breakdown of the N=8 shell known in 12Be thus extends also to the 10He system.Comment: 5 pages, 5 figure

Differential Diagnosis of New-Onset Pulmonary Ground Glass Changes During the COVID-19 Pandemic: a Case Report

The paper describes a clinical case of hypersensitivity pneumonitis in a young patient during the COVID-19 pandemic when the patient having complaints of dyspnea and interstitial lung changes as ground glass opacity was initially unambiguously diagnosed with viral COVID-related bilateral pneumonia. The chief computed tomography manifestations in the lung were infiltrative inflammatory changes as numerous areas of predominantly interstitial infiltration by the type of ground glass, with consolidation areas and reticular changes, varying in extent, peripheral localization, mainly in the lower lobes and with the 25–50% involvement of the right and left lung parenchyma. The diagnosis of hypersensitivity pneumonitis was confirmed by cytological and histological examinations of the biopsy material obtained during bronchoscopy using a set of biopsies and endobronchial cryobiopsy.This clinical case demonstrates that the chest computed tomography detection of pulmonary ground glasstype changes is a reason for further patient examinations and requires morphological verification of the diagnosis, since the cost of a diagnostic error is the life of a patient

Alkaloid content variability in the seeds of narrow-leafed lupine accessions from the VIR collection under the conditions of the Russian Northwest

Alkaloid content was assessed in the seeds of 59 narrow-leafed lupine (Lupinus angustifolius L.) accessions from the VIR collection in the environments of Leningrad Province. The selected set included accessions of different statuses (wild forms, landraces, and advanced cultivars) and different years of introduction to the collection. Alkaloids were analyzed using gas-liquid chromatography coupled with mass spectrometry. Concentrations of main alkaloids: lupanine, 13-hydroxylupanine, sparteine, angustifoline and isolupanine, and their total content were measured. The total alkaloid content variability identified in the seeds of the studied set of accessions was 0.0015 to 2.017 %. In most cases, the value of the character corresponded to the accession’s status: modern improved cultivars, with the exception of green manure ones, entered the group with the range of 0.0015–0.052 %, while landraces and wild forms showed values from 0.057 to 2.17 %. It is meaningful that the second group mainly included accessions that came to the collection before the 1950s, i. e., before the times when low-alkaloid cultivars were intensively developed. Strong variability of the character across the years was observed in the accessions grown under the same soil and climate conditions in both years. In 2019, the average content of alkaloids in the sampled set was 1.9 times higher than in 2020. An analysis of weather conditions suggested that the decrease in alkaloid content occurred due to a significant increase in total rainfall in 2020. Searching for links between the content of alkaloids and the type of pod (spontaneously non-dehiscent, or cultivated, spontaneously dehiscent, or wild, and intermediate) showed a tendency towards higher (approximately twofold in both years of research) total alkaloid content in the accessions with the wild pod type and the nearest intermediate one compared to those with the pod non-dehiscent without threshing. The correlation between the average total alkaloid content and seed color, reduced to three categories (dark, or wild, light, or cultivated, and intermediate), was significantly stronger in the group with dark seeds (5.2 times in 2019, and 3.7 times in 2020). There were no significant differences in the percentage of individual alkaloids within the total amount either between the years of research or among the groups with different pod types or the groups with different seed coat colors

Structural Features of Cast and Quenched Cobalt–Niobium Alloys

Методами металлографии и EBSD-анализа исследованы особенности формирования структуры при b>a (ГЦК>ГПУ)-полиморфном превращении в бинарном сплаве Co–3,5Nb. Показано, что при постепенном охлаждении закристаллизовавшегося слитка в каждом b-зерне сплава происходит зарождение кристаллов a-фазы нескольких ориентаций из 4 возможных в соответствии с ориентационными соотношениями Вассермана. Разориентация субструктуры по длине кристаллов в литом сплаве не превышает 1°. После закалки структура сплава Co–3,5Nb заметно измельчается. При этом в несколько раз возрастает разориентация элементов субструктуры по длине мартенситных кристаллов, что является следствием высокого уровня закалочных микронапряжений.Specific features of structure formation at the b>a (fcc>hcp) polymorphic transformation in Co–3.5Nb binary alloy have been investigated by metallography, scanning and transmission electron microscopies, and electron backscattering diffraction analysis. It is shown that gradual cooling of a crystallized ingot induces nucleation of .-phase crystals of several orientations (of the four ones that are possible in correspondence with the Wassermann orientation relationships) in each b-grain of the alloy. Misorientation of the substructure along the martensite-crystal length in the cast alloys does not exceed 1°. After subsequent quenching, the structure of Co–Nb alloy becomes significantly refined. In addition, misorientation of substructure elements along the martensite-crystal length increases several times, which is a consequence of the high level of quenching microstress in martensite.Исследование выполнено в рамках государственного задания по теме «Структура» (№ г. р. АААА-А18-118020190116-6).The study was carried out within the framework of the state task on the topic “Structure” (no. G. R. AAAA18-118020190116-6)

OBTAINING A SHARP CUBE TEXTURE DURING ROLLING AND ANNEALING IN THIN TAPES FROM A BINARY ALLOY OF COPPER AND YTTRIUM

Проведено исследование структуры и процесса текстурообразования в бинарном сплаве Cu-1%Y при холодной деформации прокаткой со степенью порядка 99 % и последующем рекристаллизационном отжиге. Показана принципиальная возможность реализации совершенной кубической текстуры в тонкой ленте из сплава меди с иттрием. Определены оптимальные режимы рекристаллизационного отжига, позволяющие получить биаксиальную текстуру с содержанием кубических зерен {001} ± 10° на поверхности текстурованной ленты более 95 %.The structure and texture formation are investigated in Cu-1%Y binary alloy subjected to 99 % cold rolling followed by recrystallization annealing. The possibility of obtaining a perfect cubic texture in a thin tape made of a binary alloy copper with yttrium is shown. Optimum annealing conditions are determined to form a perfect biaxial texture with more than 95% cubic grains {001}±10° on the surface of the textured tape in the Cu-1%Y alloy.Работа выполнена при поддержке проекта УрО РАН № 15-17-2-16 и гранта РФФИ № 16-03-00043