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מאמרים קשורים
A UKST survey of blue objects towards the Galactic centre - seven additional fields We are searching for early-type stars towards the Galactic centre whichare potentially young objects situated within the inner few kiloparsecsof the disk. Photographic photometry from the UK Schmidt Telescope hasbeen used to identify the bluest candidates in nineteen Schmidt fields(centred close to the Galactic centre). We have previously obtainedFLAIR low dispersion spectroscopy for three of these fields to estimatespectral types and here we present spectroscopy for an additional sevenfields. Combining the results for all ten fields, 56 stars wereinitially classified as early-B type. Estimates of the equivalent widthsof their Balmer and He i lines have been used to estimate atmosphericparameters and 32 targets have effective temperatures greater than orequal to 17 000 K (corresponding to a spectral type of B3 or earlier).The spectra of seven of these targets also have absorption lines due toO Ii and Si Iii and can be reliably classified as early-B type.Additionally 78 stars have estimated effective temperatures between 11000 and 16 000 K with a further a further 50 objects identified aslate-B (or early-A) type. All but two of the early B-type candidateshave magnitudes in the range 12.0<= V<= 16.0, and our bestestimates of their distance suggest that they could be close to (i.e.R_g<3 kpc), or even beyond the Galactic centre.
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הכנס מאמר חדש
לינקים קשורים
הכנס לינק חדש
משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
קבוצת-כוכבים: | עקרב |
התרוממות ימנית: | 16h58m08.26s |
סירוב: | -36°39'09.7" |
גודל גלוי: | 10.256 |
תנועה נכונה: | -0.1 |
תנועה נכונה: | -3.1 |
B-T magnitude: | 10.443 |
V-T magnitude: | 10.272 |
קטלוגים וכינוים:
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