Generation of 2 .mu.W average output power at 13.9 nm from a table-top
laser-pumped Ni-like Ag laser operating at 5 Hz repetition rate using a
silver-coated helical target which is rotated and advanced such that the
target surface is renewed between pulses, is described. Greater than
2.times.10.sup.4 soft x-ray laser pulses were obtained using a single
target. Similar results were obtained at 13.2 nm for Ni-like Cd using a
cadmium-coated target. Uninterrupted operation of laser-pumped soft x-ray
lasers at a repetition rates of about 10 Hz for periods of several hours
enables the generation of pulsed, high average power soft x-rays for
applications. Other embodiments of the renewable laser target are
described.