Fast-Ignition Fuel-Assembly:Theory and Experiments

R. Betti, C.D. Zhou, W. TheobaldK. Anderson, A. Solodov

Laboratory for Laser Energetics5th Fusion Science Center Meeting

February 28, Chicago, IL

FSC

C. Zhou, W. Theobald, R. Betti, P.B. Radha, V. Smalyuk, C.K.Li et al, Phys. Rev. Lett. 98: 025004 (2007)

Arb

itra

ry u

nit

s

Energy (MeV)

4 6 8 10 12 14 16 18 200

The maximum R during the burn can be inferredfrom the downshift of the tail of the primary proton spectrum for targets with a 25 atm D-He3 fill

5MeV 14.7MeVBirth energy

9.7MeV E -1.5MeV *broadening =8.2 MeV downshift

2burnmax 0.25g/cmρR

DHe3 Primary Proton spectrum

Fit ofspectrum

FSC

The areal density is measured during the burn.Protons from secondary D-3He reactions are slowed down by the shell areal density

FSC

C. Zhou, W. Theobald, R. Betti, P.B. Radha, V. Smalyuk, C.K.Li et al, Phys. Rev. Lett. 98: 025004 (2007)

FSC

C. Zhou, W. Theobald, R. Betti, P.B. Radha, V. Smalyuk, C.K.Li et al, PRL98: 025004 (2007)

DHe3 Secondary Proton spectrum

Reconstructedspectra

A complete set of hydro-scaling relations is derivedfor fast-ignition target design

C.D. Zhou and R. Betti, submitted to Phys. Plasmas

1.85

0.9 7

345( )

3 10iVP Gbar

Slow implosions lead to a low pressure, low temperature fuel assembly optimal for cone-in-shell targets

FSC1.25

0.15 7

3( )

3 10iVT keV

Next step: slow implosions of cone-in-shell targets