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מאמרים קשורים
Pulkovo compilation of radial velocities for 35495 stars in a common system.
Not Available
| Bispectrum speckle interferometry of the massive protostellar object S140 IRS 1: Evidence for multiple outflows
Bispectrum speckle interferometry is employed to explore the immediateenvironment of the deeply embedded young stellar object S140 IRS 1. AK'-band (2.0-2.3 mu m) diffraction-limited resolution of 76 mas ( ~ 70AU) is achieved with the SAO 6 m telescope, as well as a dynamical rangeof more than 8 mag and a field of view of 13'' x 21''. Our imageexhibits many previously unseen complex structures. In addition to thebright, elongated, and very clumpy feature pointing from the centralsource to the south-east, which was already discussed in a previouspaper (Schertl et al. \cite{Schertl00}), we find several arc-likestructures north-east of IRS 1, extended diffuse emission south of IRS1, and four new point sources. The diffuse and fragmentary structuresclose to IRS 1 appear to trace circumstellar material swept up byenergetic outflows. In combination with molecular line emission mapsfrom the literature, our image provides direct confirmation that twodistinct bipolar outflow systems continue to be driven from IRS 1 onscales between 3\arcsec and 100\arcsec. A system of three arc-likestructures to the north-east is consistent with cavities excavated by aprecessing jet or wind-driven outflow. We discuss the implications forthe nature of the central source. Based based on observations obtainedat the Special Astrophysical Observatory with the 6 m telecope.
| High-resolution near-infrared study of the deeply embedded young stellar object S140 IRS 3
We explore the structures immediately surrounding the high-mass youngstellar object S140 IRS 3 within the L1204 molecular cloud. We haveobtained a bispectrum speckle interferometric K-band image with aresolution of 150 mas and a seeing-limited molecular hydrogen lineemission image of IRS 3. Our speckle image resolves IRS 3 into threepoint sources, a close binary with separation 0.63'' and a thirdcomponent 1.3'' away. A rough assessment of the system stabilitysuggests that the IRS 3 triple system is unstable. Our speckle imagealso reveals extended diffuse emission of very complex morphology aroundIRS 3. An extended diffuse feature north-east of IRS 3 displays aremarkable sf S-shaped structure. This feature is the innermost part ofan at least 15'' long extended structure, which is pointing towards abow-shock like patch located 90'' away from IRS 3. We find strong H_2line emission associated with this feature, suggesting the presence ofshocks, caused by the collision of outflowing material with the ambientmedium. The sf S-shaped structure of this feature can be well reproducedby a model assuming a precessing outflow from IRS 3a. Furthermore, wefind several elongated features pointing away from IRS 3 in a southerndirection. Some of these features also exhibit strong H_2 line emission,demonstrating that IRS 3 drives outflows in several directions. Part ofthe results presented in this paper are based on observations obtainedat the German-Spanish Astronomical Centre, Calar Alto, operated by theMax-Planck-Institute for Astronomy, Heidelberg, jointly with the SpanishNational Commission for Astronomy. The speckle observations werecollected at the Special Astrophysical Observatory with the 6 mtelecope.
| Diffraction-limited bispectrum speckle interferometry and speckle polarimetry of the young bipolar outflow source S140 IRS1
We present bispectrum speckle interferometry and speckle polarimetry ofthe deeply embedded infrared bipolar outflow source S140 IRS1, a massiveprotostellar object in the L1204 molecular cloud. Using the SAO 6 mtelescope, we obtained 280 mas resolution polarization maps of S140 IRS1as well as a K-band image with diffraction-limited resolution lambda /Dof 76 mas, which is the highest angular resolution image of a youngoutflow source ever obtained in the infrared. Our data suggest that thecentral source is marginally resolved with a FWHM diameter ofapproximately 20 mas ( ~ 20 AU). The most remarkable feature in ourimage is a bright extended and very clumpy structure pointing away fromthe central source in exactly the same direction as the blue-shifted COoutflow lobe. A centro-symmetric pattern of high polarization in thisfeature suggests that we see scattered light from the central source. Weinterprete this feature as the clumpy inner surface of a partiallyevacuated cavity in the circumstellar envelope around IRS1, which hasbeen excavated by the strong outflow from IRS1.
| Mesures de vitesses radiales. VIII. Accompagnement AU sol DU programme d'observation DU satellite HIPPARCOS
We publish 1879 radial velocities of stars distributed in 105 fields of4^{\circ} \times 4^{\circ}. We continue the PPO series \cite[(Fehrenbachet al. 1987;]{Feh87} \cite[Duflot et al. 1990, 1992 and 1995),]{Du90}using the Fehrenbach objective prism method. Table 1 only available inelectronic form at CDS via to cdsarc.u-strasbg.fr (130.79.128.5) or viahttp://cdsweb.u-strasbg.fr/Abstract.html
| Sur la loi d'absorption interstellaire
Not Available
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משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | קפיאוס |
| התרוממות ימנית: | 22h21m51.79s |
| סירוב: | +63°08'23.9" |
| גודל גלוי: | 6.952 |
| מרחק: | 195.312 פארסק |
| תנועה נכונה: | 31.2 |
| תנועה נכונה: | 14.4 |
| B-T magnitude: | 7.047 |
| V-T magnitude: | 6.96 |
קטלוגים וכינוים:
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