A Japanese Plan of Receiver Developments for LMSA/ALMA

We present a baseline plan of Japanese receiver developments for the Large Millimeter Submillimeter Array (LMSA) and the Atacama Large Millimeter Array (ALMA). Two receiver cartridge layouts for ALMA band 8 (385 – 500 GHz) have been proposed based on a quasi-optical sideband separation. These cartridges will be evaluated in a secondary focal receiver system with the Atacama Submillimeter Telescope Experiment (ASTE), which is one of Japanese R&D project of the LMSA and the ALMA. The ASTE 10 m submillimeter-wave telescope has been pre-installed at Nobeyama since February 2000 and will be installed at Pampa la Bola (el. 4800 m) in northern Chile in November 2001. Japanese candidates for the ALMA cryocooler are reported.