Detection of a new methanol maser line with ALMA

Aims. We aimed at investigating the structure and kinematics of the gaseous disk and outflows around the massive YSO S255 NIRS3 in the S255IR-SMA1 dense clump. Methods. Observations of the S255IR region were carried out with ALMA at two epochs in the compact and extended configurations. Results. We serendipitously detected a new, never predicted, bright maser line at about 349.1 GHz, which most probably represents the CH$_3$OH $14_{1} - 14_{0}$ A$^{- +}$ transition. The emission covers most of the 6.7 GHz methanol maser emission area of almost 1$^{\prime\prime}$ in size and shows a velocity gradient in the same sense as the disk rotation. No variability was found on the time interval of several months. It is classified as Class II maser and probably originates in a ring at a distance of several hundreds AU from the central star.Comment: 4 pages, 4 figures, accepted by Astronomy and Astrophysic

On additive binary problems with semiprime numbers of a specific form

The paper is devoted to methods of solution of binary additive problems with semiprime numbers, which form sufficiently "rare" subsequences of the natural series. Additional conditions are imposed on these numbers; the main condition is belonging to so-called Vinogradov interval

The distribution density of square value probabilities functionality from trajectories of wiener process

In the article authors develop an approach to calculating the statistic development probability for composite functions of square values in Gaussian casual process trajectories. Calculating distribution density for additive composite functions is based on standard Wiener process trajectories. Authors have developed a density formula for uniformly convergent decomposition, with x = 0. The convergence is exponentially fas

Risk process with stochastic premiums

The Cramer-Lundberg model with stochastic premiums which is natural generalization of classical dynamic risk model is considered. Using martingale technique the Lundberg inequality for ruin probability is proved and characteristic equations for Lundberg coefficients are presented for certain classes of stochastic premiums and claims. The simple diffusion and de Vylder approximations for the ruin probability are introduced and investigated similarly to classical Cramer-Lundberg set-up. The weak and strong invariance principles for risk processes with stochastic premiums are discussed. Certain variants of the strong invariance principle for risk process are proved under various assumptions on claim size distributions. Obtained results are used for investigation the rate of growth of the risk process and its increments. Various modifications of the LIL and Erdos-Renyi-type SSLN are proved both for the cases of small and large claims

RESEARCH OF THE MAIN DIRECTIONS OF FORECASTING OF COST INDICATORS OF DEVELOPMENT OF AVIATION ENGINEERING

Authors have analysed features of cost forecasting on development of aviation engineering of new generation. It is shown that modeling of both the process of development, and its technical and economic indicators presents certain difficulties. The factors influencing reducing cost of development of perspective aviation engineering are revealed and also the main directions of cost reduction on its development are offered

RESEARCH OF THE MAIN DIRECTIONS OF FORECASTING OF COST INDICATORS OF DEVELOPMENT OF AVIATION ENGINEERING

Authors have analysed features of cost forecasting on development of aviation engineering of new generation. It is shown that modeling of both the process of development, and its technical and economic indicators presents certain difficulties. The factors influencing reducing cost of development of perspective aviation engineering are revealed and also the main directions of cost reduction on its development are offered

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