Abstract: A lithographic apparatus includes a collector configured to collect radiation from a radiation source, the collector including a plurality of shells forming separate compartments, and a cleaning arrangement including a gas inlet and a gas outlet, the cleaning arrangement being configured to clean surfaces of the plurality of shells by guiding a gas flow from the inlet through the compartments to the outlet. The cleaning arrangement includes a distribution system configured to divide the gas flow into several sub flows, each of the sub flows corresponding to one or more of the compartments, and a control system configured to control the relative amount of the sub flows.

Abstract: A lithographic apparatus comprising: an illumination system for providing a projection beam of radiation; a gas pressure controlled article clamp for clamping an article to be placed in a beam path of the projection beam of radiation; and a pressure circuit for controlling the article clamp, comprising a supply line for connection with the article clamp. According to the invention, a buffer volume is provided for providing a buffered gas pressure pulse in the supply line. In this way, faster clamp response times can be realized.