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تسجيل مستخدم جديدVLBI imaging of the gravitational lenses B1422+231 and MGJ0414+0534
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E. Ros
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We present wide-field images of the quadruple gravitational lenses B1422+231 and MGJ0414+0534 obtained from global Very Long Baseline Interferometry (VLBI) observations at 8.4 GHz on 23 November 1997. We present also a lens model for MGJ0414+0534, which reproduces the core positions and flux densities of the VLBI images, combining a singular isothermal ellipsoid with external shear, and a singular isothermal sphere to represent, respectively, the main lens galaxy and its neighbor, a faint galaxy near one of the images.
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We observed the quadruple gravitationally lensed image of MGJ0414+0534 on 23 November 1997 with a global VLBI array at 8.4 GHz. We report wide-field imaging results of its four components at submilliarcsecond resolution, displaying complex core-like
and jet-like extended structures. A simple model combining a singular isothermal ellipsoid to represent the main lens galaxy, external shear, and a singular isothermal sphere to represent an additional, nearby object accounts well for the core positions and flux densities of the VLBI images. This model predicts delays between the different lensed images of several weeks.
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