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מאמרים קשורים
Interstellar Extinction Along the Camelopardalis and Perseus Border Interstellar extinction in a ~ 100 sq. degree area at theCamelopardalis and Perseus border is investigated. The study is basedon the results of photoelectric photometry of 455 stars in theseven-color Vilnius photometric system published earlier. The nearest100 stars with Hipparcos parallaxes show that the extinction starts togrow at a distance of 110--150 pc. At a distance of 1 kpc theextinction A_V is within 1.2 and 2.4 mag. At larger distances theextinction determination is affected by the limiting magnitude effect.At distances >1.5 kpc a number of O--B stars with the extinctionsbetween 2 and 4 mag are found.
| Photometry and Classification of Stars Along the Camelopardalis and Perseus Border Seven-color photometry in the Vilnius system for 309 stars down to 12.5mag in the area along the galactic equator near the Camelopardalis andPerseus border is presented. Photometric spectral and luminosity classesof the stars are determined.
| Spectral classifications in the near infrared of stars with composite spectra. II. Study of a sample of 180 stars A sample of 180 supposedly composite-spectrum stars has been studied onthe basis of spectra obtained in the near infrared (8370-8780 Angstroms)at a dispersion of 33 Anstroms/mm. The objective was to study the coolercomponents of the systems. Of our sample, 120 are true compositespectra, 35 are hot spectra of types B, F and 25 are Am stars. We find astrong concentration of the cooler components of the composite spectraaround G8III. In view of the difficulty of classifying compositespectra, because of the super position of an early type dwarf and a latetype giant or supergiant spectrum, we have made several tests to controlthe classification based upon the infrared region. Since all tests gavepositive results, we conclude that our classifications can be consideredas being both reliable and homogeneous. Table \ref{tab1} is alsoavailable electronically at the CDS via anonymous ftp 130.79.128.5 orhttp://cdsweb.u-strasbg.fr/Abstracts.html} Based upon observationscarried out at Observatoire de Haute-Provence (CNRS).
| A spectrophotometric survey of stars along the Milky Way. IV In the present paper a catalogue of spectrophotometric quantities,spectral types, monochromatic magnitudes and colour equivalents is givenfor all stars brighter than the magnitude m4400 = 10.5 in aregion of the Milky Way in Perseus. No absorption is found for starscloser than about r = 100 pc. The absorbing clouds are situated atdistances closer than 1 kpc and at about 2.5 kpc in the local arm andthe Perseus arm, respectively. The space between the two arms is freefrom absorption. It is also concluded that the Perseus arm continuesbeyond l = 140 deg, containing not only hydrogen gas but also dust to atleast l = 150 deg), while the content of OB stars decreases abruptly atl = 140 deg.
| A survey of stars with composite spectra. Not Available
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משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
קבוצת-כוכבים: | ג'ירף |
התרוממות ימנית: | 04h00m28.71s |
סירוב: | +52°56'50.8" |
גודל גלוי: | 8.645 |
מרחק: | 115.207 פארסק |
תנועה נכונה: | 23.2 |
תנועה נכונה: | 13.8 |
B-T magnitude: | 9.111 |
V-T magnitude: | 8.684 |
קטלוגים וכינוים:
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