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arXiv · astro-ph/9506085

Optical appearance of the gravitational lens system B0218+35.7

F. Grundahl·J. Hjorth
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Abstract

We present high-resolution CCD images (FWHM=0.6"-0.7") of the compact gravitational lens system B0218+35.7 obtained at the Nordic Optical Telescope. Using aperture and PSF photometry we detect the two closely separated (335 mas) components A and B as well as the lensing galaxy. In the optical B seems to be very much brighter than A, opposite to the radio morphology. This suggests that most of the light from A is absorbed in the lensing galaxy, possibly by a giant molecular cloud located in the line-of-sight to component A. The lensing galaxy appears to be a late-type galaxy at a small inclination. For future variability studies we present calibrated photometry of the system and its immediate surroundings, even though the relative faintness of A will make it difficult to obtain an optical time delay even with the Hubble Space Telescope.

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F. Grundahl, J. Hjorth. 1995-06-14. Optical appearance of the gravitational lens system B0218+35.7. https://doi.org/10.1093/mnras%2F275.1.l67

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