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SW Sextantis in an excited, low state We present low-resolution spectrophotometric optical observations of theeclipsing nova-like cataclysmic variable SW Sex, the prototype of the SWSex stars. We observed the system when it was in an unusual low state.The spectrum is characterized by the presence of strong Heii and Civemission lines as well as the normal single peaked Balmer emissionlines. The radial temperature profile of the disk follows the expectedT~ R-3/4 only in the outer parts and flattens off inside 0.5times the white dwarf Roche lobe radius. The single peaked emissionlines originate in a region above the plane of the disk, at the positionof the hot spot.
| The Tokyo PMC catalog 90-93: Catalog of positions of 6649 stars observed in 1990 through 1993 with Tokyo photoelectric meridian circle The sixth annual catalog of the Tokyo Photoelectric Meridian Circle(PMC) is presented for 6649 stars which were observed at least two timesin January 1990 through March 1993. The mean positions of the starsobserved are given in the catalog at the corresponding mean epochs ofobservations of individual stars. The coordinates of the catalog arebased on the FK5 system, and referred to the equinox and equator ofJ2000.0. The mean local deviations of the observed positions from theFK5 catalog positions are constructed for the basic FK5 stars to comparewith those of the Tokyo PMC Catalog 89 and preliminary Hipparcos resultsof H30.
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| A library of stellar spectra Spectra for 161 stars having spectral classes O-M and luminosity classesV, III, and I have been incorporated into a library available onmagnetic tape. The spectra extend from 3510 to 7427 A at a resolution ofabout 4.5 A. The typical photometric uncertainty of each resolutionelement in the spectra is on the order of 1 percent while broad-bandvariations are smaller than 3 percent. Potential uses for the libraryinclude population synthesis of galaxies and clusters, tests of stellaratmosphere models, spectral classification, and the generation of colorindices having arbitrary wavelength and bandpass.
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Datos observacionales y astrométricos
Constelación: | Perseo |
Ascensión Recta: | 04h32m40.83s |
Declinación: | +31°24'18.0" |
Magnitud Aparente: | 8.702 |
Distancia: | 740.741 parsecs |
Movimiento Propio en Ascensión Recta: | -0.3 |
Movimiento Propio en Declinación: | -11.3 |
B-T magnitude: | 9.104 |
V-T magnitude: | 8.736 |
Catálogos y designaciones:
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