Multi-wavelength study of the star-formation in the S237 H II region

We present a detailed multi-wavelength study of observations from X-ray, near-infrared to centimeter wavelengths to probe the star formation processes in the S237 region. Multi-wavelength images trace an almost sphere-like shell morphology of the region, which is filled with the 0.5--2 keV X-ray emission. The region contains two distinct environments - a bell-shaped cavity-like structure containing the peak of 1.4 GHz emission at center, and elongated filamentary features without any radio detection at edges of the sphere-like shell - where {\it Herschel} clumps are detected. Using the 1.4 GHz continuum and $^{12}$CO line data, the S237 region is found to be excited by a radio spectral type of B0.5V star and is associated with an expanding H{\sc ii} region. The photoionized gas appears to be responsible for the origin of the bell-shaped structure. The majority of molecular gas is distributed toward a massive {\it Herschel} clump (M$_{clump}$ $\sim$260 M$_{\odot}$), which contains the filamentary features and has a noticeable velocity gradient. The photometric analysis traces the clusters of young stellar objects (YSOs) mainly toward the bell-shaped structure and the filamentary features. Considering the lower dynamical age of the H\,{\sc ii} region (i.e. 0.2-0.8 Myr), these clusters are unlikely to be formed by the expansion of the H\,{\sc ii} region. Our results also show the existence of a cluster of YSOs and a massive clump at the intersection of filamentary features, indicating that the collisions of these features may have triggered cluster formation, similar to those found in Serpens South region.Comment: 21 pages, 14 figures, 1 table, Accepted for publication in The Astrophysical Journa

A Search for Small-Scale Clumpiness in Dense Cores of Molecular Clouds

We have analyzed HCN(1-0) and CS(2-1) line profiles obtained with high signal-to-noise ratios toward distinct positions in three selected objects in order to search for small-scale structure in molecular cloud cores associated with regions of high-mass star formation. In some cases, ripples were detected in the line profiles, which could be due to the presence of a large number of unresolved small clumps in the telescope beam. The number of clumps for regions with linear scales of ~0.2-0.5 pc is determined using an analytical model and detailed calculations for a clumpy cloud model; this number varies in the range: ~2 10^4-3 10^5, depending on the source. The clump densities range from ~3 10^5-10^6 cm^{-3}, and the sizes and volume filling factors of the clumps are ~(1-3) 10^{-3} pc and ~0.03-0.12. The clumps are surrounded by inter-clump gas with densities not lower than ~(2-7) 10^4 cm^{-3}. The internal thermal energy of the gas in the model clumps is much higher than their gravitational energy. Their mean lifetimes can depend on the inter-clump collisional rates, and vary in the range ~10^4-10^5 yr. These structures are probably connected with density fluctuations due to turbulence in high-mass star-forming regions.Comment: 23 pages including 4 figures and 4 table

Study of the filamentary infrared dark cloud G192.76+00.10 in the S254-S258 OB complex

We present results of a high resolution study of the filamentary infrared dark cloud G192.76+00.10 in the S254-S258 OB complex in several molecular species tracing different physical conditions. These include three isotopologues of carbon monoxide (CO), ammonia (NH$_3$), carbon monosulfide (CS). The aim of this work is to study the general structure and kinematics of the filamentary cloud, its fragmentation and physical parameters. The gas temperature is derived from the NH$_3$ $(J,K) = (1,1), (2,2)$ and $^{12}$CO(2--1) lines and the $^{13}$CO(1--0), $^{13}$CO(2--1) emission is used to investigate the overall gas distribution and kinematics. Several dense clumps are identified from the CS(2--1) data. Values of the gas temperature lie in the ranges $10-35$ K, column density $N(\mathrm{H}_2)$ reaches the value 5.1 10$^{22}$ cm$^{-2}$. The width of the filament is of order 1 pc. The masses of the dense clumps range from $\sim 30$ M$_\odot$ to $\sim 160$ M$_\odot$. They appear to be gravitationally unstable. The molecular emission shows a gas dynamical coherence along the filament. The velocity pattern may indicate longitudinal collapse.Comment: 10 pages, 9 figures, accepted for publication in Research in Astronomy and Astrophysic

Providing tire stiffness tests in LMS Virtual.Lab-Imagine.Lab AMESim co-simulation

Tire stretched string model creating and stiffness tests performance are discussed. Main emphasis is put on the possibility of using data of string modal decomposition (string eigen forms and eigen frequencies) obtained from ABAQUS and co-simulation with Imagine.Lab AMESim which provide tuning of represented model. Also comparison of virtual simulated tests with real tests is performed.Рассмотрено создание струнной модели растяжения шины и проведено ее испытание на жесткость. Главный акцент сделан на возможности использования данных для струнной модели из программы ABAQUS и на проведении совместного моделирования с помощью программы Imagine.Lab AMESim, которая обеспечивает настройку представленную модель. Выполнено сравнение результатов проведенного моделирования с результатами реальных тестов

NGC 7538 : Multiwavelength Study of Stellar Cluster Regions associated with IRS 1-3 and IRS 9 sources

We present deep and high-resolution (FWHM ~ 0.4 arcsec) near-infrared (NIR) imaging observations of the NGC 7538 IRS 1-3 region (in JHK bands), and IRS 9 region (in HK bands) using the 8.2m Subaru telescope. The NIR analysis is complemented with GMRT low-frequency observations at 325, 610, and 1280 MHz, molecular line observations of H13CO+ (J=1-0), and archival Chandra X-ray observations. Using the 'J-H/H-K' diagram, 144 Class II and 24 Class I young stellar object (YSO) candidates are identified in the IRS 1-3 region. Further analysis using 'K/H-K' diagram yields 145 and 96 red sources in the IRS 1-3 and IRS 9 regions, respectively. A total of 27 sources are found to have X-ray counterparts. The YSO mass function (MF), constructed using a theoretical mass-luminosity relation, shows peaks at substellar (~0.08-0.18 Msolar) and intermediate (~1-1.78 Msolar) mass ranges for the IRS 1-3 region. The MF can be fitted by a power law in the low mass regime with a slope of Gamma ~ 0.54-0.75, which is much shallower than the Salpeter value of 1.35. An upper limit of 10.2 is obtained for the star to brown dwarf ratio in the IRS 1-3 region. GMRT maps show a compact HII region associated with the IRS 1-3 sources, whose spectral index of 0.87+-0.11 suggests optical thickness. This compact region is resolved into three separate peaks in higher resolution 1280 MHz map, and the 'East' sub-peak coincides with the IRS 2 source. H13CO+ (J=1-0) emission reveals peaks in both IRS 1-3 and IRS 9 regions, none of which are coincident with visible nebular emission, suggesting the presence of dense cloud nearby. The virial masses are approximately of the order of 1000 Msolar and 500 Msolar for the clumps in IRS 1-3 and IRS 9 regions, respectively.Comment: 27 pages, 18 figures, 5 tables. Accepted for publication in MNRA

Договір про неконкуренцію (заборону конкуренції): актуальні проблеми українського законодавства

Ця стаття присвячена дослідженню догово­рів про неконкуренцію (заборону конкуренції) в українському законодавстві, їхньому правовому регулюванню. Цей механізм використовується для регулювання відносин між роботодавцем та працівником з метою захисту законних інтере­сів першого. Розглянуто найпоширеніші науко­ві підходи щодо визначення правової природи в доктрині права договорів про неконкуренцію, надано їм оцінку. Авторами встановлено, що за своєю суттю договори про неконкуренцію - зо­бов'язання із негативним змістом, незважаючи на те, що вони не передбачені Цивільним кодек­сом України. В статті проведено аналіз законодавства за­хідних країн про договори про неконкуренцію, зокрема Франції, Італії та США. Автори прихо­дять до висновку, що положення законодавств цих країн подібні і встановлюють такі вимоги до договорів цього типу: 1) письмова форма; 2) ви­нагорода для працівника; 3) строк дії зобов'я­зання, який становить в основному кілька років, територія дії та діяльність, яку заборонено вико­нувати. Якщо бракує якоїсь умови, то це підстава для визнання договору недійсним. Проаналізовано українське законодавство, зо­крема Закон України «Про стимулювання розвит­ку цифрової економіки в Україні», який передба­чає укладання договорів про неконкуренцію для резидентів Дія Сіті. Автори доходять висновку, що в цілому українське трудове та цивільне законодавства не допускають укладання договорів про неконкуренцію, крім винятку, передбачено­го вказаним Законом, оскільки порушують права людини на працю та підприємницьку діяльність, а законів, які можуть обмежити ці права не існує. Проводиться аналіз судової практики, яка є діаметрально протилежною, в деякій мірі супере­чливою, оскільки перебуває на стадії формуван­ня. Оскільки договори про неконкуренцію мають місце на практиці, то автори доходять висновку, що ця тематика підлягає подальшому досліджен­ню

The disk-outflow system in the S255IR area of high mass star formation

We report the results of our observations of the S255IR area with the SMA at 1.3 mm in the very extended configuration and at 0.8 mm in the compact configuration as well as with the IRAM-30m at 0.8 mm. The best achieved angular resolution is about 0.4 arcsec. The dust continuum emission and several tens of molecular spectral lines are observed. The majority of the lines is detected only towards the S255IR-SMA1 clump, which represents a rotating structure (probably disk) around the young massive star. The achieved angular resolution is still insufficient for conclusions about Keplerian or non-Keplerian character of the rotation. The temperature of the molecular gas reaches 130-180 K. The size of the clump is about 500 AU. The clump is strongly fragmented as follows from the low beam filling factor. The mass of the hot gas is significantly lower than the mass of the central star. A strong DCN emission near the center of the hot core most probably indicates a presence of a relatively cold ($\lesssim 80$ K) and rather massive clump there. High velocity emission is observed in the CO line as well as in lines of high density tracers HCN, HCO+, CS and other molecules. The outflow morphology obtained from combination of the SMA and IRAM-30m data is significantly different from that derived from the SMA data alone. The CO emission detected with the SMA traces only one boundary of the outflow. The outflow is most probably driven by jet bow shocks created by episodic ejections from the center. We detected a dense high velocity clump associated apparently with one of the bow shocks. The outflow strongly affects the chemical composition of the surrounding medium.Comment: 19 pages, 23 figures, accepted by The Astrophysical Journa

The BM@N Experiment at JINR: Status and Physics Program

BM@N (Baryonic Matter at Nuclotron) is the first experiment to be realized at the accelerator complex of NICA-Nuclotron at JINR (Dubna, Russia). The aim of the experiment is to study interactions of relativistic heavy ion beams with energy up to of strange mesons, multi-strange hyperons and light hyper-nuclei which are produced in nucleus-nucleus collisions close to the kinematic threshold. The BM@N set-up, the experimental program and first results of technical runs are presented