In the cadmium photoionization laser, atomic Cd irradiated by emission from an 12-eV plasma is selectively photoionized to the 4d**95s**2 **2D levels of Cd** plus by the removal of an inner-shell (4d) electron with high cross section, resulting in high gain on the 441. 6/325. 0-nm transitions to the lower 4d**1**05p **2**p**0 levels. Anisotropies in the X-ray emission and the expanding hot-electron front from the plasma affect directly the temporal and spatial dependence of the gain and have not been fully investigated to date. Experiments are reported with this laser in which the temporally resolved gain has been mapped in three spatial dimensions so as to fully specify the gain and allow appropriate deductions about the X-ray source. The maximum on-axis peak gain, 3. 2 cm**-**1, was achieved at 4. 5 mm from the target for 10-mbar Cd pressure. Closer to the target the on-axis gain decreases; the evidence of the temporal evolution of gain indicates that the gain is truncated by the rapid arrival of a front of hot electrons from the plasma. Beyond 4. 5 mm the on-axis gain decreases as the X-ray flux dimensions. The plasma is symmetrical about the axis normal to the target so that these profiles can be translated to a complete 3-D map of the gain.
|Title of host publication||XV International conference on quantum electronics, Baltimore, MD, USA|
|Publisher||Optical Soc of America|
|Number of pages||3|
|Publication status||Published - 1987|