We have applied the InfraRed Flux Method (IRFM) to a sample of 475 dwarfs and subdwarfs in order to derive their effective temperatures with a mean accuracy of about 1.5%. We have used the new homogeneous grid of theoretical model atmosphere flux distributions developed by Kurucz (1991, 1993) for the application of the IRFM. The atmospheric

Bidimensional spectroscopy of the circumnuclear region (central 10" x 8") of the Seyfert 2 galaxy NGC 1068 has been performed by means of an optical fiber system. The 95 spectra obtained simultaneously include the [N II] λλ6548, 6583, Hα, and [S II] λλ6716,6731 emission lines. In the inner regions, the velocity field obtained by cross-correlating

Broadband optical spectra of a sample of 15 low-mass X-ray binaries (LMXBs) is obtained in the range of 4000-9000 A. The spectra are fitted with combinations of standard accretion disc models and secondary star templates. The slope steepness relating to an optically thick accretion disc and x-ray heating of the outer parts of the disc is discussed

We compare optical and near-infrared colors of disks and bulges in a diameter-limited sample of inclined, bright, nearby, early-type spirals. Color profiles along wedge apertures at 15^deg^ from the major axis and on the minor axis on the side of the galaxy opposite to the dust lane are used to assign nominal colors for the inner disks (at 2 scale

Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However, immediately beneath the convection zone and at the edge of the energy-generating core, the sound-speed variation is somewhat smoother in the sun than it is in the model. This could be a consequence of