A gas flow management system may comprise a first and second enclosing walls at least partially surrounding first and second respective spaces; a system generating plasma in the first space, the plasma emitting extreme ultraviolet light; an elongated body restricting flow from the first space to the second space, the body at least partially surrounding a passageway and having a first open end allowing EUV light to enter the passageway from the first space and a second open end allowing EUV light to exit the passageway into the second space, the body shaped to establish a location having a reduced cross-sectional area relative to the first and second ends; and a flow of gas exiting an aperture, the aperture positioned to introduce gas into the passageway at a position between the first end of the body and the location having a reduced cross-sectional area.