e-VLBI and Other Developments at the EVN MkIV Data Processor at JIVE

 R.M. Campbell and A. Szomoru

Joint Institute for VLBI in Europe, the Netherlands

Oral presentation

We review the capabilities of the European VLBI Network (EVN) MkIV Data Processor at JIVE, briefly touching on operations for EVN/global observations.  The principal new correlator feature is recirculation, which can "time-share" the correlator for channel bandwidths ≤8 MHz, and thus enables larger arrays at the highest spectral resolution.  Network developments include the new Yebes 40m antenna and the first participation of the QUASAR stations in EVN experiments.  Progress in e-VLBI has led to real-time 512 Mbps observations as standard EVN operations.  We have had 21 proposal-driven e-EVN experiments since April 2008, with FITS files made available the same or the next day.  Three Astronomer's Telegrams on transient sources have resulted from this fast turn-around.  Effelsberg and Shanghai began regular participation in e-EVN arrays in 2008, and we have developed means to combine data from multiple MERLIN antennas in with Cambridge's to provide more sensitivity to extended emission.  Various tests and demonstrations have provided our first e-VLBI fringes from more stations (Hartebeesthoek, TIGO, Urumqi, Hobart, Kashima, Westford).  We have obtained full 1024 Mbps data without dropping packets from Effelsberg, Westerbork, and Onsala.