Axial particle and soft X-ray emission from the fast capillary discharge

摘要

Summary form only given, as follows. Recently, Prof. Rocca of Colorado State University reported the lasing of gas filled capillary discharges, the achievement of saturated gains, and numerous applications connected with the coherence of the soft X-ray radiation. However, the use of X-rays generated in the capillary (similarly as in the case of X-rays generated by laser produced plasma) is connected with a risk of bombardment of the target/detection equipment by multiply charged ions. In contrast to a laser plasma, it is necessary to pre-fill the capillary volume by a working gas to obtain a properly functioning discharge. To reduce X-ray propagation losses, it is desirable to create a sufficiently large pressure drop (usually due to separation by "long thin pipe") towards the target/detection equipment. This "cork", however, modifies the ion trajectories in an unpredictable way, increasing the rate of charge-exchange collisions etc. A direct measurement of area-of-interest exposure to ions is also complicated because of massive photoemission by XUV radiation. A combination of an electrostatic and/or magnetostatic deflecting system with dielectric track detectors (insensitive to electromagnetic radiation) provides a promising tool for analysis-even though not (due to the hours-long etching in hot NaOH and the tedious analysis by at least a thousand times magnifying optical microscope) very elegant.