The eSMA ("expanded SMA") combines the SMA, JCMT and CSO into a single facility, providing enhanced sensitivity
and spatial resolution owing to the increased collecting area at the longest baselines. Until ALMA early
science observing (2011), the eSMA will be the facility capable of the highest angular resolution observations at
345 GHz. The gain in sensitivity and resolution will bring new insights in a variety of fields, such as protoplanetary/
transition disks, high-mass star formation, solar system bodies, nearby and high-z galaxies. Therefore the
eSMA is an important facility to prepare the grounds for ALMA and train scientists in the techniques.
Over the last two years, and especially since November 2006, there has been substantial progress toward
making the eSMA into a working interferometer. In particular, (i) new 345-GHz receivers, that match the
capabilities of the SMA system, were installed at the JCMT and CSO; (ii) numerous tests have been performed
for receiver, correlator and baseline calibrations in order to determine and take into account the effects arising
from the differences between the three types of antennas; (iii) First fringes at 345 GHz were obtained on August
30 2007, and the array has entered the science-verification stage.
We report on the characteristics of the eSMA and its measured performance at 230 GHz and that expected
at 345 GHz. We also present the results of the commissioning and some initial science-verification observations,
including the first absorption measurement of the C/CO ratio in a galaxy at z=0.89, located along the line of sight to the lensed quasar PKS 1830-211, and on the imaging of the vibrationally excited HCN line towards
European VLBI is undergoing a rapid development. On one hand
electronic or e-VLBI is changing the very nature of the European VLBI
Network (EVN), on the other hand a dramatically increased time
resolution will enable the EVN to image vast areas of sky at
unprecedented resolution. The resulting increase of data volumes will
require new calibration tools and new ways of computing, storing and
distributing data products.
Technological advances are changing the nature of VLBI. Disk based recording has already led to sustantial increases in sensitivity and with the advent of new telescopes and data acquisition systems VLBI will start penetrating the micro-Jansky sky. With the employment of fibre based communication networks as the basis for production, real-time VLBI networks will become a reality. This changes the way VLBI is done and removes bottlenecks in operation and scientific exploration. At the output side, fantastic new correlator output data rates and the ability to deal with these via powerful PC clusters promises to expand the typical VLBI field-of-view to scales previously reserved for connected, short baseline interferometers. These developments require new algorithms for user processing, as well as new interfaces to present the product to the users.