Measuring H0 with CLASS B1608+656: The Second Season of VLA Monitoring
نویسنده
چکیده
The four-component gravitational lens CLASS B1608+656 has been monitored with the VLA for two seasons in order to search for time delays between the components. These time delays can be combined with mass models of the lens system to yield a measurement of H0. The component light curves show significantly different behavior in the two observing seasons. In the first season the light curves have maximum variations of ∼5%, while in the second season the components experienced a nearly monotonic ∼40% decrease in flux. We present the time delays derived from a joint analysis of the light curves from the two seasons.
منابع مشابه
A Determination of H0 with the CLASS Gravitational Lens B1608+656: III. A Significant Improvement in the Precision of the Time Delay Measurements
The gravitational lens CLASS B1608+656 is the only four-image lens system for which all three independent time delays have been measured. This makes the system an excellent candidate for a high-quality determination of H0 at cosmological distances. However, the original measurements of the time delays had large (12–20%) uncertainties, due to the low level of variability of the background source...
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