Observations with a mid-plane reciprocating probe in MAST

A fast reciprocating probe has recently been installed on MAST. It has been used to measure the outboard, mid-plane scrape off layer (SOL) of L-mode plasmas, and to study the intermittent fluctuations in the SOL in L-mode and ELMy H-mode discharges. In this paper, the system and the experiments are introduced.