TY - JOUR AU - Anand, M. AU - Kahaly, S. AU - Ravindra Kumar, G. AU - Krishnamurthy, M. AU - Sandhu, A. S. AU - Gibbon, P. TI - Enhanced hard x-ray emission from microdroplet preplasma JO - Applied physics letters VL - 88 SN - 0003-6951 CY - Melville, NY PB - American Institute of Physics M1 - PreJuSER-51647 SP - 181111 PY - 2006 N1 - Record converted from VDB: 12.11.2012 AB - We perform a comparative study of hard x-ray emission from femtosecond laser plasmas in 15 mu m methanol microdroplets and Perspex target. The hard x-ray yield from droplet plasmas is similar or equal to 68 times more than that obtained from solid plasmas at 2x10(15) W cm(-2). A 10 ns prepulse at about 5% of the main pulse appears to be essential for hard x-ray generation from droplets. Hot electron temperature of 36 keV is measured from the droplets at 8x10(14) W cm(-2), whereas a three times higher intensity is needed to obtain similar hot electron temperatures from Perspex plasmas. Particle-in-cell simulations with very long scale-length density profiles support experimental observations. (c) 2006 American Institute of Physics. KW - J (WoSType) LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:000237321600011 DO - DOI:10.1063/1.2200761 UR - https://juser.fz-juelich.de/record/51647 ER -