The new generation receivers

In connection with the long-term plans to extend the capabilities of the Plateau de Bure Interferometer, it is foreseen to equip all 6 antennas with a new generation of SIS receivers (NGRx). These receivers will operate in single-side-band mode at 3mm, 2mm, 1mm and 0.8mm and offer dual polarization capabilities (horizontal/vertical, each) within an IF bandwidth of 4GHz. Current plans foresee to have the installation and testing of the 3mm and 1mm receivers completed in time for the upcoming winter 2006/2007 scheduling period and to configure the system to correlate two 1GHz wide sections within the 4GHz bandwidth. Compared to the current receivers, the NGRx will offer a T$_{\rm sys}$ lower by a factor of $\sim 2$ at 1mm.

IRAM expects that regular observing will be severely reduced or even suspended during the receiver installation and testing period, i.e. for about 6-8 weeks from October to mid November. In view of this exceptional situation, IRAM may consider moving to the winter scheduling period some of the B-rated proposals of the summer period. All A-rated projects of the summer period will be kept on the observing schedule up to their completion.

Owing to uncertainties in the installation planning of the NGRx, IRAM issues this call for the current receiver generation. Should the new receivers become available for the winter semester, observations will be adjusted in spectral configuration and observing time in consultation with the principal investigators.