Vacuum System.

TAMA300 involves two 300m-long vacuum ducts of 400mm in diameter and eight vacuum chambers. The required vacuum pressure in the ducts is 1 x 10-6 Pa or lee. Since the effective baking of such a large system is not easy in practice, we adopted an ECB(Electro-Chemical Buffing) technique instead of baking, so as to reduce the outgasing rate.

The chambers for the mode cleaning cavity have been constructed in the center room(JUN. 12, 1996).

The 300m-long vacuum ducts in the east-west arm. After installation and leak check, they were pumped down to a few x 10-6 Pa(JUN. 19, 1997).