Using the semiclassical perturbation approach, we have calculated electron-, proton- and He II-impact line widths and shifts for 32 Zn I multiplets as a function of temperature and perturber density. Obtained results have been compared with the existing theoretical and experimental data
Using a semiclassical approach, we have calculated electron-, proton-, and ionized helium-impact line widths and shifts for 33 Sr I multiplets for perturber densities 10^13^cm^-3^ (for stellar plasma research) and 10^15^-10^18^cm^-3^ (for laboratory plasma research) and temperatures T=2500-50000K.
Using a semiclassical approach, we have calculated electron-, proton-, and ionized helium-impact line widths and shifts for 12 Be III and 27 B III multiplets. The obtained results have been compared with available experimental and theoretical data.
1214 individual measurements of radial velocities made with CORAVEL-type spectrometer (Tokovinin, 1987AZh....64..196T) are presented for 1134 stars in 19 northern Kapteyn's areas. Precise coordinates are given for all these stars. Proper motions of stars are taken from NLTT (Luyten, 1979, Cat. <I/98>), PPM (Roser, Bastian, 1991, Cat. <I/146> and <I/193>), NPM1 (Klemola, Hanson, Jones, 1987, Cat. <I/200>) and Four-million catalog (Kuimov, 1992, In: On the four-million catalog of stars, eds. Izd. MGU, Moscow, P.27.; Glushkova et al., 1996PAZh...22..850G). A list of suspected binary stars and stars with variable radial velocities is also given. Two-dimensional spectral classification for these area is available (Bartaya, 1979AbaOB..51....1B).
The Stark widths of singly ionized iron lines from a^6^D--z^6^D^o^ and a^6^D--z^6^F^o^ have been measured and compared with the predictions obtained on the basis of the Stark broadening regularities within similar spectra. The measurements were performed using a linear arc discharge plasma source within an electron density range of 5x10^22^m^-3^--2x10^23^m^-3^ and an electron temperature from 27000K to 30000K.
Understanding massive star formation requires comprehensive knowledge about the initial conditions of this process. The cradles of massive stars are believed to be located in dense and massive molecular clumps. In this study, we present an unbiased sample of the earliest stages of massive star formation across 20deg^2^ of the sky. Within the region 10{deg}<l<20{deg} and |b|<1{deg}, we search the ATLASGAL survey at 870um for dense gas condensations. These clumps are carefully examined for indications of ongoing star formation using YSOs from the GLIMPSE source catalog as well as sources in the 24um MIPSGAL images, to search for starless clumps. We calculate the column densities as well as the kinematic distances and masses for sources where the v_lsr_ is known from spectroscopic observations. Within the given region, we identify 210 starless clumps with peak column densities >10^23^cm^-2^. In particular, we identify potential starless clumps on the other side of the Galaxy. The sizes of the clumps range between 0.1pc and 3pc with masses between a few tens of M_{sun}_ up to several ten thousands of M_{sun}_.
We have obtained ~2.5x2.5 arcminute maps toward L1521E using the IRAM-30m telescope in transitions of various species, including C^17^O, CH_3_OH c-C_3_H_2_, CN, SO, H_2_CS, and CH_3_CCH. We derived abundances for the observed species and compared them to those obtained toward L1544. We estimated CO depletion factors using the C^17^O IRAM-30m map, an N(H2) map derived from Herschel/ SPIRE data and a 1.2 mm dust continuum emission map obtained with the IRAM-30m telescope. Similarly to L1544, c-C_3_H_2_ and CH_3_OH peak at different positions. Most species peak toward the c-C_3_H_2_ peak: C_2_S, C_3_S, HCS^+^, HC_3_N, H_2_CS, CH_3_CCH, C^34^S. C^17^O and SO peak close to both the c-C_3_H_2_ and the CH_3_OH peaks. CN and N_2_H^+^ peak close to the Herschel dust peak. We found evidence of CO depletion toward L1521E. The lower limit of the CO depletion factor derived toward the Herschel dust peak is 4.3+/-1.6, which is about a factor of three lower than toward L1544. We derived abundances for several species toward the dust peaks of L1521E and L1544. The abundances of most sulfur-bearing molecules such as C_2_S, HCS^+^, C^34^S, C^33^S, and HCS^+^ are higher toward L1521E than toward L1544 by factors of ~2-20, compared to the abundance of A-CH_3_OH. The abundance of methanol is very similar toward the two cores.