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Interstellar polarization at high galactic latitudes from distant stars. VII. A complete map for southern latitudes b < -70°
We present a detailed map of interstellar polarization for the SouthGalactic Pole (b < -70°). The map is based on new polarizationmeasurements of 183 stars of spectral classes from A to K at distancesof up to 500 pc. We use polarization data to investigate thedistribution of dust and to map the Galactic magnetic field at highsouthern Galactic latitudes and make a comparison with the oppositenorthern polar zone. In general, the magnetic field is smoother in thesouth and aligned with the global pattern. There are no extended dustystructures in the south similar to Markkanen's cloud in the north.
| Observations of Star-Forming Regions with the Midcourse Space Experiment
We have imaged seven nearby star-forming regions, the Rosette Nebula,the Orion Nebula, W3, the Pleiades, G300.2-16.8, S263, and G159.6-18.5,with the Spatial Infrared Imaging Telescope on the Midcourse SpaceExperiment (MSX) satellite at 18" resolution at 8.3, 12.1, 14.7, and21.3 μm. The large angular scale of the regions imaged (~7.2-50deg2) makes these data unique in terms of the combination ofsize and resolution. In addition to the star-forming regions, twocirrus-free fields (MSXBG 160 and MSXBG 161) and a field near the southGalactic pole (MSXBG 239) were also imaged. Point sources have beenextracted from each region, resulting in the identification over 500 newsources (i.e., no identified counterparts at other wavelengths), as wellas over 1300 with prior identifications. The extended emission from thestar-forming regions is described, and prominent structures areidentified, particularly in W3 and Orion. The Rosette Nebula isdiscussed in detail. The bulk of the mid-infrared emission is consistentwith that of photon-dominated regions, including the elephant trunkcomplex. The central clump, however, and a line of site toward thenorthern edge of the cavity show significantly redder colors than therest of the Rosette complex.
| 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.
| Spectral classification of stars with the same colours in intermediate multiband photometry - The concept of photometric 'star-box'
The concept of a photometric 'star box' is introduced for use with the UB V B1 B2 V1 G photometric system. Star boxes are employed to grouptogether all stars for which each photometric color differs by less thansome small quantity (in magnitude) from the corresponding color of agiven 'central' star. Probable causes of differences between the colorsof two stars are summarized, scatter in spectral type and luminosityclass within a single box is discussed, and the standard deviation ofnarrow-band photometric indices is calculated for stars grouped in thesame box. Dispersions in the UV and IR energy distributions of stars inthe same box are examined, and the results obtained in the seven-colorphotometric system for 113 stars are compared with the correspondingresults in a thirteen-color system. The classification of Am and Am:stars is briefly examined on the basis of star boxes.
| On the homogeneity of the spectral-energy distribution among giant E and SO galaxies and other results.
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1970AJ.....75...21L&db_key=AST
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Besorolás csoportokba:
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Pozíciós és asztrometriai adatok
| Csillagkép: | Cet |
| Rektaszcenzió: | 00h59m50.35s |
| Deklináció: | -24°33'08.6" |
| Vizuális fényesség: | 8.849 |
| Távolság: | 364.964 parszek |
| RA sajátmozgás: | -4.9 |
| Dec sajátmozgás: | -5.7 |
| B-T magnitude: | 10.004 |
| V-T magnitude: | 8.945 |
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