Speaker
Channprit Kaur
Description
See the full Abstract at http://ocs.ciemat.es/EPS2018ABS/pdf/P5.2034.pdf
X-ray and ion emission studies from low density gold targets
Channprit Kaur1, 2, S. Chaurasia1, A. Rossall3 , Nataliya G Borisenko4, A. I. Gromov4, , A. A.
Akunet4, M. N. Deo1
1
High Pressure & Synchrotron Radiation Physics Division, BARC, Mumbai 400085, India
2
Homi Bhabha National Institute, Mumbai-400094, India
3
International Institute for Accelerator Applications - Medium Energy Ion Scattering
Facility Huddersfield, United Kingdom
4
P. N. Lebedev Physics Institute, Leninsky Pr 53, Moscow, Russia
The utilization of laser plasma produced X-rays for investigating the plasma’s emission and
absorption properties and in measurement of opacity, radiography, ICF is well known. This
triggers the demand of high conversion efficiency (CE) for achieving a bright X-ray source.
In this work, enhancement in X-ray emission and reduction of kinetic energy of ions
from low density gold foam plasma is demonstrated by performing experiment and its
validation with hydrodynamic simulation. The plasma is produced by irradiation of solid
gold and gold foam targets (densities 0.193 g/cc, 0.128 g/cc and 0.0965 g/cc) with 500 ps
laser at intensities in the range of 4 x 1013-1014 W/cm2. Time resolved X-ray emission is
observed by X-ray streak camera with 10 ps resolution. The X-ray measured by streak
camera from low density gold foam shows 8.5 % enhancement in comparison to solid gold.
On the other hand, there is decrease in velocity of ions in case of low density gold foam. The
angular distribution of peak ion velocity is measured by employing Time-of-Flight technique
with four ion collectors placed at different angles (22.5º, 45º, 52º and 63º) from target normal.
The maximum peak velocity of ions is 6.8 times high in case of solid gold (31x104 m/s) in
comparison to 0.0965 g/cc (4.5 x104 m/s) gold foam towards target normal. Lower charge
states of gold ions are found in case of solid gold which are absent in gold foam as detected
by Thomson Parabola ion Spectrometer. However the difference in integrated ion flux for
both cases is less indicating the process of volumetric absorption. A hydrodynamic
simulation is performed by using POLLUX code. The results supports the volumetric
absorption of laser light in case of low density gold foam and shows a good match with our
experimental results. The detailed analysis will be presented in the conference.
