ISSN:0094-243X    

DOI:10.1063/1.46885

出版商:AIP    

年代:1994

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.46916

出版商:AIP    

年代:1994

数据来源: AIP

ISSN:0094-243X    

DOI:10.1063/1.46924

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

The dynamics of the energy absorption is studied when a thin dense aluminium laser produced plasma has been irradiated by a short pulse. X‐ray emission spectra of multi‐charged ions are observed. The calculations of the ionization dynamics, energy transfer, conductivity, and stopping power are performed basing on the hydrodynamic model. (AIP) © 1994American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.46925

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

In view of difficulties for laser acceleration of charged particles by means of other media, we followed the possibilities of accelerators for electrons interacting with laser fields without secondary means. After several schemes have shown the basic mechanism for such an acceleration, we report here the conditions for high luminosity TeV accelerators. In view of the last years progress in sub‐picosecond laser pulse generation and in the material resistivity under these conditions we present a concept for such an accelerator which is competitive to existing classical TeV accelerator schemes. © 1994American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.46929

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

The dynamics of X‐ray spectra emitted by an ultrashort laser produced plasma is studied using a 100 fs 800 nm pulses. The broadband emission is used to estimate the time dependent plasma temperature. Experimental results are in a good agreement with hydrodynamic calculations. (AIP) © 1994American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.46939

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

Current studies of optical ionization and heating of gases using KrF laser pulses are discussed. The Thomson scattered spectra reveal the evolution of the electron distribution. The stimulated Raman and Brillouin scattering instabilities are very useful for the study of the pressure dependent plasma heating, in particular the measurement of the electron temperature. (AIP) © 1994American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.46941

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

We have derived a simplified set of three dimensional equations for the propagation of an intense laser pulse in cold underdense plasma [Phys. Fluids,B5, 1336 (1993)]. A three dimensional code has recently been developed to study this set of equations. Here we report on some of the preliminary results from the 3‐d code. © 1994American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.46944

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

Results of both experimental studies and computer simulations of a laser‐induced plasma in a gas near a solid surface are presented. Particular attention is paid to two‐dimensional effects and optical properties of the plasmas with electron temperature in the range from 2 to 5 eV and electron number density from 1017to 1020cm−3. It is shown that to adequately describe the experimental data obtained for CO2laser pulses with intensity of some ten MW, a computer simulation must take into account transient beam refraction in the plasma plume and, therefore, use ray tracing procedures. Comparison with the experimental results shows that the numerical model is accurate for both IR (10 &mgr;m) and UV (0.308 &mgr;m) laser wavelengths. Modulation of a TEA CO2laser output pulse at the frequencies above 10 MHz have been observed in the case when a pulse scattered from a target passes from semi‐transparent decaying plasma near its surface. These modulations are explained using optical properties of the plasma obtained from direct measurements or computer simulations. © 1994American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.46884

出版商:AIP    

年代:1994

数据来源: AIP

摘要:

We are performing laser matter interaction studies with the P102 laser in picosecond and sub‐picosecond range at 1018W/cm2. We describe an X‐ray RbAP conical crystal spectrometer (spectral resolution 5 mA˚ in 6.86 A˚–8.5 A˚ spectral range) developed to increase its sensitivity by a factor 200 compared with the one of a plane crystal used in the same conditions. By using this spectrometer and the C850X bilamellar X‐ray streak camera (2 ps, 20 lp/mm), we have recorded tiime resolved X‐ray spectra emitted from an aluminum plasma. We observed H&agr;, He&agr;, Li‐like, Be‐like, and K&agr; lines versus time. Intensity and duration of the line emission are very dependent on the contrast ratio of the laser pulse and are interpreted as a function of the scale length of the pre plasma created before the main pulse arrives onto the target. © 1994American Institute of Physics

ISSN:0094-243X    

DOI:10.1063/1.46904

出版商:AIP    

年代:1994

数据来源: AIP