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מאמרים קשורים
A Westerbork Synthesis Radio Telescope 327 MHz Survey of the Galactic Plane
The Westerbork Synthesis Radio Telescope (WSRT) has been used to surveythe Galactic plane region 42^deg^ < l < 92^deg^ at a frequency of327 MHz. We present images of the emission within |b| < 1.6^deg^ atresolution of 1' x 1' csc δ and detection level as low as 10 mJybeam^-1^. Inspection of the survey image has produced a catalog ofnearly 4000 discrete sources with sizes less than about ~3'. The catalogof these sources and FITS files of seven images covering the survey areaare available on the World Wide Web athttp://www.ras.ucalgary.ca/wsrt_survey.html. Approximately 15% of thesources are resolved, with dimensions of 1'- 3'. The spatialdistribution of resolved sources shows concentrations toward the spiralarms and follows the warping of the Galactic disk over the length of thesurvey region, indicating that a sizable fraction is Galactic. Spectralindices are calculated for 1313 sources detected in other radio surveysat frequencies greater than 408 MHz. The resolved sources exhibit abimodal spectral index distribution, with distinct nonthermal andthermal populations. Comparison with the IRAS Point Source Catalogueresults in 118 identifications between WSRT and IRAS sources. Most ofthese are thermal radio sources associated with compact Galactic objectssuch as H II regions and planetary nebulae. A search for variabilityamong 2148 of the compact sources has resulted in 29 candidatelow-frequency variable sources.
| The Henry Draper Extension Charts: A catalogue of accurate positions, proper motions, magnitudes and spectral types of 86933 stars
The Henry Draper Extension Charts (HDEC), published in the form offinding charts, provide spectral classification for some 87000 starsmostly between 10th and 11th magnitude. This data, being highlyvaluable, as yet was practically unusable for modern computer-basedastronomy. An earlier pilot project (Roeser et al. 1991) demonstrated apossibility to convert this into a star catalogue, using measurements ofcartesian coordinates of stars on the charts and positions of theAstrographic Catalogue (AC) for subsequent identification. We presenthere a final HDEC catalogue comprising accurate positions, propermotions, magnitudes and spectral classes for 86933 stars of the HenryDraper Extension Charts.
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הכנס לינק חדש
משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | ברבור |
| התרוממות ימנית: | 20h06m00.98s |
| סירוב: | +32°28'46.9" |
| גודל גלוי: | 8.587 |
| מרחק: | 645.161 פארסק |
| תנועה נכונה: | -8.2 |
| תנועה נכונה: | -17.3 |
| B-T magnitude: | 10.521 |
| V-T magnitude: | 8.747 |
קטלוגים וכינוים:
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