# shock wave particle acceleration in laser-plasma interaction

Post on 07-Jan-2016

46 views

Embed Size (px)

DESCRIPTION

SHOCK WAVE PARTICLE ACCELERATION in LASER-PLASMA INTERACTION. G.I.Dudnikova, T.V.Leseykina ICT SBRAS. SCT-2012, Novosibirsk, June 8, 2012. Introduction & Motivation. The progress in laser technology has led to light sources delivering pulses - PowerPoint PPT PresentationTRANSCRIPT

SCT-2012, Novosibirsk, June 8, 2012SHOCK WAVE PARTICLE ACCELERATION in LASER-PLASMA INTERACTIONG.I.Dudnikova, T.V.LeseykinaICT SBRAS

NOVA Laser(1999, LLNL, petawatt)HERCULES (CUOS),Table Top Petawatt The progress in laser technology has led to light sources delivering pulses of femtosecond duration and focused intensities up to 1022 W/cm2 Introduction & Motivation

Experiments carried out in recent years on the laser-plasma interaction show the possibility of ions acceleration to high energy (tens of MeV) Compact and affordable ion accelerator based on laser produced plasmas have potential applications in many fields of science and medicine (radiography, isotopes generation, cancer therapy, inertial fusion). Two more studied mechanism of ion acceleration are TNSA (60MeV, energy spread 20%), RPA ( 30 Mev, 50%, ). The light pressure, P=2I/c, from Gigabar to Terabar may compress plasma and generate shock waves that lead to acceleration of ions due to reflection by shock front (monoenergetic component in ion spectra are produced )Introduction & MotivationTNSA accelerating ions by ultra-intense laser pulses

4 < R < 10 5 < L < 400 5 < X1< 10 2 < X2 < 52 < X1 < 10 Set -upFoil size: 3-20

Foil density: 2-100 n*, Laser pulse: circular polarized

Amplitude a: 2-50

a=sqrt(I/1.35 1018 Wcm -2 (/m) 2)Foil: full ionized H plasmaHERCULES (MI), ATF BNL (NY), Sokol-P (Snezhinsk, Russia) n*= 1.1 10^21 cm^-3, =0.8 ma=eE/ mc

Numerical Model

Numerical modelling is carried out on the basis of code UMKA2D3V*, allowing to carry out calculations of interaction of laser radiation with plasma of any complex structure and to choose type of boundary conditions for an electromagnetic field (reflection, absorption, periodic conditions). The effective algorithm of parallel calculations is created, and its realization on multiprocessing complexes MBC-15000 (Moscow) is carried out. At the decision it was used 100-150 processors of complex MBC-15000, calculation up to the moment of time to the equal 400 laser periods has occupied approximately 5000 hours of processor time.

* Vshivkov V.A., Dudnikova G.I. Comput. Technol., 2001.

- Plasma formations observed in experiment (ATF BNL) and simulated (bottom row) shadowgram and a simulated plasma profile for case filamentation and solitons for ne
Hole-boring and shock formationVhb= sqrt((1+k) I / c)

Cs=sqrt(kTe /mi) M=1.3Te=mc2sqrt(1+a2/2)

V=0.06 c

Palmer Charlotte A. J.; Dover N. P.; Dudnikova G. I., et. al Phys. Rev. Lett. 106, 014801 (2011)Ion phase spaceIon trajectoriesDistribution function

T.C.Liu, G. Dudnikova, et.al, Phys.Plasma, 18, 2011Ion densityProton energy spectraIon energy phase spaceFlat pulse R-T instability

a=32Plasma density temporal evolution. a=32, n=169 n*, d=0.25 I=1.4 10 21W/cm2, n=1.9 10 23 cm-3, d=0.25 mEnergy spectrum

Laser acceleration is potentially an affordable alternative to traditional cyclotron acceleration. Intense, high quality ion beams driven by relativistic laser plasma - the next generation ion accelerators.

Shock-like acceleration due to the ion reflection at the front of the compressed layer in the plasma lets to obtain the quasi-monoenergetic ion bunch.

In realistic geometries there are two independent obstacles to sustain quasi-mono-energetic regime of acceleration: Rayleigh-Taylor instability of plasma sheet lateral expansion of plasma

Summary

Recommended