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Now showing items 21-30 of 36
Simultaneous optical and infrared polarization measurements of blazars
(1986)
The authors present measurements of the polarization and flux of a sample of 28 blazars (21 BL Lacs and 7 OVV quasars) at optical and near-infrared wavelengths, with repeated observations for some objects. As in earlier ...
Infrared polarimetry of the nucleus of Centaurus A - The nearest blazar?
(1986)
As one of the nearest examples of an active galaxy, NGC5128 (Centaurus A) has been studied in detail over a wide range of wavelengths. The nucleus of the galaxy is seen clearly in the X-ray, radio and infrared, but is ...
The origin of the visual and infrared pulsations in the intermediate polar FO AQR (H2215-086)
(1986)
Simultaneous visual and infrared polarimetry of the intermediate polar FO Aqr (H2215-086) shows that its visual and infrared pulsations, seen at the rotation period of the white dwarf, are not circularly polarized. This ...
Infrared photometry of the nuclei of early-type radio galaxies
(1986)
The authors have obtained near- and mid-infrared photometry of the nuclei of both strong and weak radio galaxies. The implication of these data are that a relatively small percentage, ≅15 per cent, of radio ellipticals ...
An optical and near-infrared study of the AM Herculis-type binary CW 1103+254
(1985)
All main components of the AM Herculis-type binary CW 1103 + 254 can be distinguished by means of observations encompassing optical and near-IR photometry and polarimetry, together with optical spectroscopy and spectropolarimetry. ...
Coordinated multisite observations of the variability of BL Lac
(1985)
The authors present the results of multisite observations of the optical polarization of BL Lac, together with some flux measurements, at a time when BL Lac was relatively faint. The level of polarization varies in a manner ...
Infrared and optical polarimetry of AM Herculis
(1984)
Circular polarization observations of AM Herculis have been obtained at wavelengths from 0.55 micron (V) to 2.2 micron (K) using a simultaneous three-channel polarimeter. Polarizations of up to 20 per cent were observed ...
Imaging and polarimetry of the galactic-center in the near infrared
(1984)
IR images of the Galactic center in H, K, L-prime and M are the bases of the present measurements of positions, magnitudes and colors for 35 sources which can be divided into two classes: those with colors typical of ...
Simultaneous IR and optical light curves of 2A0311−227
(1983)
The complex wavelength dependence shown by the light curves of the AM Herculis type binaries such as 2A0311−227 (EFERI) and AM Her itself has led to suggestions that accretion occurs onto both magnetic poles of the white ...
The AM Herculis type binary E1405-451
(1983)
The authors report photometry and polarimetry of the AM Her-type binary E1405-451. For the first time circular polarization has been detected in such an object at wavelengths longer than 1 μm. The light curves and polarization ...