Modelling of a nitrogen x-ray laser pumped by capillary discharge

• Authors: Pavel Vrba , Miroslava Vrbová , Nadezhda Bobrova , Pavel Sasorov
• Languages of publication: EN

Abstracts

EN

We performed computer modelling of a fast electrical discharge in a nitrogen-filled alumina capillary in order to discover discharge system parameters that may lead to efficient recombination pumping of soft X-ray laser with active medium created by H-like nitrogen ions. The space-time dependences of pinch plasma quantities were found by means of a one-dimensional MHD code. Time dependences of populations of all ionisation states and populations of selected energy levels of lithium-, helium- and hydrogen-like nitrogen ions were evaluated using the FLY code as a post-processor. The population inversion was found at the quantum transition corresponding to the Balmer α-line of N6+ ions and the resulting gain factor was evaluated for different capillary radii, initial pressure, electric current peaks and periods. A gain factor of 1 cm−1 spanning the time interval of 1 ns was found for an optimised arrangement with capillary radius 1.5 mm, peak current 50 kA, quarter period 40 ns and filling gas pressure 0.5 kPa. It is pointed out that even higher values of the gain factor may be achieved with thinner capillaries and shorter current pulses, e.g. a gain factor of 6 cm−1 is achieved if the capillary radius is 0.5 mm, peak current 56 kA, quarter period 15 ns, and filling nitrogen pressure 3.9 kPa.

Keywords

EN

MHD simulations; Z-pinch, Ion kinetics; Recombination pumping; X-ray laser; 52.58.Lq; 52.59.Ye; 52.65.Kj

• Publisher: De Gruyter Open
• Journal: Open Physics
• Year: 2005
• Volume: 3
• Issue: 4
• Pages: 564-580

Dates

published

1 - 12 - 2005

online

1 - 12 - 2005

Contributors

author

Pavel Vrba

• Institute of Plasma Physics, The Academy of Sciences of the Czech Republic, Za Slovankou 3, 182 00, Prague 8, Czech Republic

author

Miroslava Vrbová

• The Faculty of Nuclear Sciences and Physical Engineering, Czech Technical University in Prague, Břehová 7, 115 19, Prague 1, Czech Republic

author

Nadezhda Bobrova

• Institute of Theoretical and Experimental Physics, Bolshaya Cheremushkinskaya 25, 117218, Moscow, Russia

author

Pavel Sasorov

• Institute of Theoretical and Experimental Physics, Bolshaya Cheremushkinskaya 25, 117218, Moscow, Russia

References

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Identifiers

DOI

10.2478/BF02475613