Polarization Monitoring of the Lens System JVAS B0218+357

Gravitational Lens Time Delays Using Polarization Monitoring

Gravitational lens time delays provide a means of measuring the expansion of the Universe at high redshift (and therefore in the ‘Hubble flow’) that is independent of local calibrations. It was hoped that many of the radio lenses found in the JVAS/CLASS survey would yield time delays as these were selected to have flat spectra and are dominated by multiple compact components. However, despite e...

The JVAS / CLASS 6 ′ ′ to 15 ′ ′ Lens Search

NICMOS images of JVAS/CLASS gravitational lens systems

We present Hubble Space Telescope (HST) infrared images of four gravitational lens systems from the JVAS/CLASS gravitational lens survey and compare the new infrared HST pictures with previously published WFPC2 HST optical images and radio maps. Apart from the wealth of information that we get from the flux ratios and accurate positions and separations of the components of the lens systems that...

a study on construction of iranian life tables: the case study of modified brass logit system

چکیده ندارد.

Radio follow - up of the γ - ray flaring gravitational lens JVAS B 0218 + 357

We present results on multifrequency Very Long Baseline Array (VLBA) monitoring observations of the double-image gravitationally lensed blazar JVAS B0218+357. Multi-epoch observations started less than one month after the γ-ray flare detected in 2012 by the Large Area Telescope on board Fermi, and spanned a 2-month interval. The radio light curves did not reveal any significant flux density var...