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מאמרים קשורים
Galactic Clusters with Associated Cepheid Variables. VI. Anonymous van den Bergh (C0634+031) and CV Monocerotis
A photometric UBVI_KC study, based upon a compilation of new andpreviously published photometry, is presented for the clustersurrounding the 5.38 day Cepheid CV Mon. Photoelectric, photographic,and CCD observations are presented for 200 stars lying within ~8' of CVMon, and the data are used with spectroscopic observations for starsnear the Cepheid to investigate the reddening and distance of clustermembers. The reddening law for the cluster field is described by therelation E_U - B/E_B - V = 0.77, and the ratio of total to selectiveextinction for the dust clouds obscuring cluster stars is characterizedby R = A_V/E_B - V = 3.20 +/- 0.04 s.e. The foreground dust complex islocated at a distance of ~900-1100 pc, whereas the cluster itself is1.65 +/- 0.03 kpc distant ( = 11.08 +/- 0.03 s.e.). CVMon shares not only a spatial coincidence with cluster stars-a featureconfirmed by star counts-but also a similar radial velocity andestimated age. Its derived luminosity as a cluster member is = -3.37 +/- 0.08 s.e., and its derived space reddening is E_B - V = 0.75+/- 0.02 [E_B - V(B0) = 0.80 +/- 0.02]. There is evidence for thepresence of two background groups in the field, one lying immediatelybeyond the cluster (d = 1.86 +/- 0.03 kpc) and a more distant group (d =3.02 +/- 0.08 kpc). The cluster itself exhibits photometricproperties-upper-main-sequence dispersion and main-sequencegaps-consistent with rapid rotation for hot cluster members. Suchfeatures are common in Cepheid-age clusters.
| Identification of 106 new infrared carbon stars in the IRAS Point Source Catalog - Near-infrared photometry and their space distribution in the galaxy
A method based solely on IR colors - the combination of near-IR and IRAScolors - is used to identify 106 new IR carbon stars (IRCS). It is shownthat the proportion of IRCS in a region of the IRAS two-color diagrampreviously thought to contain the largest concentration of such stars isnot as large as expected for the faintest objects. A local spatialnumber density of about 12 IRCS/sq kpc is estimated. It is shown to beuniform within 5 to 11 kpc from the galactic center. The local ratio ofIRCS to optical carbon stars is found to be about 35 percent. A totalrestitution rate of about 10 to the -4 solar masses/yr/sq kpc isderived. The efficiency of the combination of near and mid-IR photometryfor the study of AGB stars is confirmed.
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משמש של הקבוצה הבאה
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | חד קרן |
| התרוממות ימנית: | 06h37m24.00s |
| סירוב: | +02°53'11.2" |
| גודל גלוי: | 9.1 |
| תנועה נכונה: | -2.4 |
| תנועה נכונה: | 5.6 |
| B-T magnitude: | 12.409 |
| V-T magnitude: | 9.374 |
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