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Interstellar polarization at high galactic latitudes from distant stars. V. First results for the South Galactic Pole
We present the first results of our interstellar polarization programmefor the South Galactic Pole (b<-70degr ). The new observations (43stars) combined with previously published data show that there is asubstantial interstellar polarization in this area of the sky. Startingat a distance of 300 pc, we have found stars with P > 0.3% includingone for which P ~ 0.6%. These measurements lead to the conclusion thatthere is a significant amount of interstellar dust at high southgalactic latitudes. Futhermore, there is a remarkable alignment seenover the South Polar Cap: for most stars the directions of polarizationvectors are aligned with the longitude l ~ 80degr , close to theexpected direction of the global magnetic field. In this respect the SGPseems to differ strongly from its northern counterpart.
| A kinematic and abundance survey at the galactic poles
The DDO intermediate band system is used to obtain detailed informationabout abundance gradients and velocity dispersions in the galaxy, withan emphasis on the properties of halo stars in the range of from 1 to 5kpc. The DDO abundance index is calibrated agianst (Fe/H) for metal-poorstars, with a resulting gradient of about -0.2 per kpc. However, whenthe sample is divided into two subsamples with (Fe/H) less than -0.5 andequal to or greater than -0.5, the gradients are -0.14 and 0.00,respectively. DDO observations of about 1000 stars, mostly G5-K5 giants,show that the velocity dispersion increases both with decrease inmetallicity and increase in z distance. The abundances found for high-zstars are similar to the A-star results of Rodgers (1971) in that abouthalf the K giants above 1 kpc appear to have solar abundances.
| Stellar population samples at the galactic poles. III - UBVRI observations of proper motion stars near the south pole and the luminosity laws for the halo and old disk populations
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1976ApJS...30..351E&db_key=AST
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תצפית ומידע אסטרומטרי
| קבוצת-כוכבים: | לויתן |
| התרוממות ימנית: | 00h59m04.65s |
| סירוב: | -23°41'28.8" |
| גודל גלוי: | 9.463 |
| תנועה נכונה: | 73.6 |
| תנועה נכונה: | -56.1 |
| B-T magnitude: | 10.32 |
| V-T magnitude: | 9.534 |
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