Imaging a Jet Base - Prospects with M87

TL;DR

This paper discusses VLBI observations of M87's jet base, revealing rapid motions and emphasizing the potential of future high-frequency, high-cadence observations with VSOP2 to advance understanding of jet formation.

Contribution

It presents initial VLBA results on M87's jet base and advocates for daily 43 GHz observations with VSOP2 to improve temporal resolution.

Findings

Detected rapid motions in the jet base region.

Initial VLBA observations demonstrate the feasibility of studying jet dynamics.

Future observations with VSOP2 could significantly enhance understanding of jet formation.

Abstract

M87 provides the best opportunity to study the base of a jet where it is collimated and accelerated. The size of that region scales with the mass of the black hole, and M87 has the best combination of high mass, proximity to the Earth, and presence of a bright jet. VLBI observations of M87 can probe regions under 100 gravitational radii where theoretical studies suggest that the jet formation and acceleration occurs. A one-year sequence of 43 GHz observations every 3 weeks on the VLBA is being used to study the structure and dynamics in this region. Initial results from that effort are reported here, including the observation of rapid motions - sufficiently rapid that more frequent observations are planned for early 2008. The contribution ends with a discussion of prospects for future VLBI observations of M87 with VSOP2. For VSOP2, a strong recommendation is made that a series of daily observations at 43 GHz be planned.