The invention is directed to an arrangement for the optical detection of a moving target flow for pulsed energy beam pumped radiation generation based on a plasma. It is the object of the invention to find a novel possibility for detection of a moving target flow for energy beam pumped radiation generation based on a plasma which allows reliable orientation of the excitation beam on the target without the detector being subjected to influence and damage due to radiation emitted by the plasma. According to the invention, this object is met in that a target generator provides a target flow with relatively constant target states in an interaction point, a sensor unit is directed to a detection point which lies close to the interaction point in the direction of the path. The sensor unit contains a projection module which has a defined focal length and numerical aperture, so that only transmission light reflected from the detection point is received by the projection module and is directed via a light waveguide to the detection module which is arranged at a spatial distance, and the sensor unit also contains a detection module.