Inner jet structure of AGNs as seen by RadioAstron snapshot observations

RadioAstron has performed different kinds of AGN observations: imaging sessions with a rich baseline coverage, and snapshots with only one or a few baselines present. These snapshots are products of the AGN survey and monitoring program, and it is challenging to extract the object structure from them due to the sparsity. Such observations contain unique information: they cover about 5 years, the longest baselines up to 350,000 km were achieved in this mode. We propose and develop a novel approach to use the snapshot data either on its own or together with imaging observations to model the jet structure in more details. We provide examples of how supplementing rich imaging observations with sparse snapshots yields a higher effective resolution. This resolution allows to better probe the inner jet and core regions where its formation and collimation occur. The wide time coverage of snapshot observations will let us track changes in this compact structure with the RadioAstron sub-milliarcsecond resolution on the scales of years.