SPACE-RESOLVED OBSERVATION OF FALSE GAIN IN SOFT-X-RAY LASERS

OZAKI T KURODA H

T. Ozaki et H. Kuroda, SPACE-RESOLVED OBSERVATION OF FALSE GAIN IN SOFT-X-RAY LASERS, Journal of the Optical Society of America. B, Optical physics, 13(9), 1996, pp. 1873-1878

40

INGLESE

Article

Optics

Journal of the Optical Society of America. B, Optical physics → ACNP

0740-3224

13

9

1996

1873 - 1878

ISI

0740-3224(1996)13:9<1873:SOOFGI>2.0.ZU;2-Z

The results of space-resolved investigations on false amplification ob served in soft-x-ray laser experiments that are due to axial plasma ex pansion are presented. Space-resolved observations show a difference i n the spontaneous-emission intensities of the N Balmer-alpha line for plasmas with different active media lengths, which can be a cause of o verestimation of gain coefficients. The deviations of the intensities are found to be small for optically thick lines and for lower pump int ensities. Modeling calculations that include the effects of axial expa nsions are also performed that support the experimental observations. The different N Balmer-alpha intensity profiles observed for short and long active media lengths are attributed to expansion of the cylindri cal plasma in the axial direction, which tends to force plasmas with s maller volumes to expand and cool at an enhanced rate. (C) 1996 Optica l Society of America.