Now showing items 1-7 of 7
Latitude distributions and lifetimes of star-spots on G dwarfs in the alpha Persei cluster
We present a set of maximum-entropy reconstructions of the star-spot distributions on two rapidly rotating G dwarfs in the alpha Persei cluster, from spectra taken at the William Herschel Telescope on three nights in 1996 ...
Hot UV bright stars in globular clusters
We have obtained medium-resolution spectra of seven UV-bright stars discovered on images of four southern globular clusters obtained with the Ultraviolet Imaging Telescope (UIT). Effective temperatures, surface gravities ...
The profiles of polarized broad Hα lines in radio galaxies
We present spectropolarimetric observations of seven broad-line radio galaxies. We find significantly polarized broad Hα emission in four objects including two, Arp 102B and 3C 390.3, which have double-peaked line profiles. ...
Boron in the very metal-poor star BD-13 3442
The Goddard High Resolution Spectrograph (GHRS) of the Hubble Space Telescope (HST) has been used to observe the boron 2500 °A region of BD −13 3442. At a metallicity of [Fe/H]=−3.00 this is the most metal- poor star ever ...
Beam delivery of femtosecond laser radiation by diffractive optical elements
A novel beam-forming and delivery technique for high-power laser beams for the generation of well-defined intensity distributions based on diffractive optical elements is reported. It will be shown that nonlinear beam ...
The evolved B[e] star HD 87643: observations and a radiation-driven disc wind model for B[e] stars
New high resolution spectroscopic and medium resolution spectropolarimetric data, complemented with optical broad and narrow band imaging, of the B[e] star HD 87643 are presented. The spectrum of HD 87643 exhibits the ...