Volume 80, Number 2, October 2007
|Number of page(s)||5|
|Section||Physics of Gases, Plasmas and Electric Discharges|
|Published online||14 September 2007|
Laser absorption in microdroplet plasmas
Tata Institute of Fundamental Research - 1 Homi Bhabha Road, Mumbai 400 005, India
2 John-von-Neumann Institute for Computing, ZAM, Forschungszentrum Jülich - D-52425 Jülich, Germany
Accepted: 24 August 2007
We present experimental measurements of the absorption of ultrashort laser pulses by 15 μm diameter methanol microdroplets. The droplet absorbs upto 70% of the incidence laser energy in the presence of a prepulse at intensities of about 1.5 1016 W cm-2. In the absence of a prepulse, the absorption is only about 20%. Simultaneous measurements of X-ray yield (12 keV to 350 keV) and the absorption in the droplet plasma, shows that our earlier measurements of efficient generation (Anand M. et al. Appl. Phys. Lett., 88 (2006) 181111) of hard X-rays from the droplet plasma is due to the increased absorption in the droplets in the presence of optimum prepulse. 1-D PIC simulations, mimicing the mass-limited droplet density profile, demonstrate the effectiveness of the large scale-length droplet plasma in providing optimal conditions for resonant laser absorption energy and generation of hot electrons.
PACS: 52.38.Ph – X-ray, γ-ray, and particle generation / 52.25.Os – Emission, absorption, and scattering of electromagnetic radiation / 79.20.Ds – Laser-beam impact phenomena
© Europhysics Letters Association, 2007
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.