This morning the pressure achieved was 1.44E-7 mbar. Leak testing showed an overall leak rate of 1.5E-10 mbar l/s, this is below the previous leak rate but still significantly above the leak rate from elog 141 of the CARME chamber on its own. Spraying helium, a leak is visible on the VAT gate valve on the interaction chamber (inside of the ring). The leak rate increases to ~2.3E-10 mbar l/s. No increase in the leak rate was observed elsewhere on CARME or the interaction chamber. It was decided to vent again and replace the gasket and inspect the knife edges for the valve. 

The valve was removed and the gasket was replaced. Several scratches are visible on the gasket which may be the cause of the leak (or damage may have been done during dismounting). While vented, the backing line was re-organised. The scroll pump is now on the outside of the ring for easier access (see attached image), the turbo pump was rotated to move all power cables and the backing line to the outside of the ring. 

CARME and the interaction chamber were pumped down again and the ion gauge was activated. Vacuum can be followed via the vac plot or by grafana on the carme-gsi computer (anydesk required).