目录
图像
上传图像
DSS Images Other Images
相关文章
Starlight polarization and CO observations towards the Lupus clouds
We performed an observational study of the dark filaments Lupus 1 andLupus 4 using both polarimetric observations of 190 stars and a sampleof 72 ^12CO profiles towards these clouds. We have estimated lowerlimits to the distances of Lupus 1 and Lupus 4 (>~ 140 and >~ 125pc, respectively). The observational strategy of the survey allows us tocompare the projected magnetic field in an extended area around eachcloud with the magnetic field direction observed to prevail along theclouds. Lupus 4 could have collapsed along the magnetic field lines,while in Lupus 1 the magnetic field appears to be less ordered, havingthe major axis of the filaments parallel to the large-scale projectedmagnetic field. These differences would imply that both filaments havedifferent pattern evolutions. From the CO observations we have probedthe velocity fields of the filaments and the spatial extension of themolecular gas with respect to the dust.
| Photometry of F-K type bright giants and supergiants. I - Intermediate band and H-Beta observations
Over 1500 observations of 560 bright giants and supergiants of types F-Kare presented and compared to the observations by Gray and Olsen (1991).The present results include intermediate-band which is slightlydifferent from the Stromgren data by Gray and Olsen due to a differentwidth for the v filter. A systematic difference in m(1) - M(1) withdecreasing temperature is noted in the two H-Beta data sets, and thecorrelations are defined.
| Photometry of F-K type bright giant and supergiants. II - Calibration on indices in terms of luminosity reddening and abundance of F-type stars
Abstract image available at:http://adsabs.harvard.edu/cgi-bin/nph-bib_query?1991AJ....102.1826E&db_key=AST
| The calibration of the Stromgren photometric system for A, F and early G supergiants. I - The observational data
An empirical calibration of the Stromgren uvby-beta photometric systemfor the A, F, and early G supergiants is being derived. This paperexplains the observational program and the photometric reductiontechniques used and presents a catalog of new Stromgren photometry forover 600 A, F, and G supergiants.
| Estimation of spectral classifications for bright southern stars with interesting Stromgren indices
This paper investigates the degree of success with which uvby photometrycan be applied to predict spectral classifications for 947 A, F, and Gstars brighter than an apparent magnitude of 8.3 and with four-colorindices indicating some kind of interesting, unusual, or peculiarspectrum. One or several possible spectral classifications are estimatedfor each star from photometry alone, double stars are distinguished, andthe estimates are compared with published classifications. The resultsshow that the framework provided by uvby photometry can be extended toinclude most G and K stars, reddened stars, peculiar stars, and certaintypes of double star.
|
提交文章
相关链接
提交链接
下列团体成员
|
观测天体数据
目录:
|
INHABITED SKY
