May 2007 Work supported by the U.S. Department of Energy under grants DE-FG52-03NA00064, DE-FG52-07NA28058 and other grants and contracts Experiments With Astrophysical Applications R. Paul Drake University of Michigan

Page January NNSA One way to accomplish shock acceleration Plot is for achievable nD 2 = 1.4 x cm -1 Parameters will increase with future, larger nD 2 From R.P. Drake, Physics of Plasmas, Nov. (2000)

Page January NNSA Why HED Lab Astro is important to NNSA Providing trained young people –The scientific population at the NNSA labs is aging rapidly –Over the next few years the National Ignition Facility will need a new generation –I could have easily placed 5 new Ph.D.s this past year Advancing NNSA-relevant fundamental science –Most work in the labs is programmatic –Universities have a role to play in doing detailed, systematic, fundamental work Establishing a national community and national advocacy

Page January NNSA Current projects Supernova-relevant hydrodynamics –Blast-wave driven instabilities –On Omega (Carolyn Kuranz in NLUF talks) –On NIF Kelvin Helmholtz –Relevant to astrophysics and ICF –On NIKE (Eric Harding at HESDUP session) Radiative shocks –Interesting objects ! –Astrophysically relevant –On Omega –On LIL collaborating with team led by Claire Michaut X-ray diagnostics

Page January NNSA Most of our current work uses Omega One of our shots at the Omega laser Collaborators: LLNL – Remington, Robey, Miles, Edwards, Hansen, Froula, others LLE – Knauer, Boehly Arizona – Arnett Chicago – Plewa Stony Brook – Glimm, Zhang, Swesty NRL – Aglitskiy, Weaver France – Bouquet, Koenig, Busquet

Page January NNSA Here is what such lasers do to a material The laser is absorbed at less than 1% of solid density From Drake, High-Energy-Density Physics, Springer (2006) Rad xport, high-v plas Hydro, rad hydro

Page January NNSA Shock waves establish the regime of an experiment

Page January NNSA Supernova 1987A motivates scaled hydrodynamic instability experiments SN 1987A –A core-collapse supernova –Early high-Z x-ray lines with large Doppler shifts –Early glow from radioactive heating –The issue is the post-core-collapse explosive behavior In 20 years of simulations –Only one (Kifonidis, 2006) makes fast enough high-Z material –3D simulations coupling all the interfaces where initial conditions matter are not feasible –NIF experiments can do this –Omega experiments address a single interface SN1987A, WFPC2, Hubble Kifonidis, 2003

Page January NNSA Here is a typical target for our supernova hydrodynamics experiments Precision structure inside a shock tube Hydrodynamics: – L >> mfp ; Re > 10 5 ; – small heat conduction & radiation Experiment design: Carolyn Kuranz

Page January NNSA We build precise, innovative targets Acrylic cone Gold cone Laser-driven surface Side view 1 mm Targets: Mike Grosskopf, Donna Marion, Robb Gillespie, UROP team

Page January NNSA We obtain data from two orthogonal directions Mid- 1990’s data Dec. 06 data at 21 ns Data and analysis: Carolyn Kuranz

Page January NNSA We are now observing the role of complex initial conditions in spike penetration Interferogram of complex surface on component provided by GA (analysis: Kai Ravariere) Preliminary data on mix layer thickness Data and analysis: Carolyn Kuranz

Page January NNSA We collaborate with simulation groups to evaluate our results and validate codes Work with the FLASH Center (Chicago), to include 3D adaptive modeling, has now begun. 3D FLASH simulations of recent experiments (density display) Two-mode system ns 7.5 ns 19.5 ns Single eggcrate mode.

Page January NNSA We lead a team to prepare for HED hydrodynamics beyond simulation on NIF The unresolved issue in exploding stars –The 3D behavior of a diverging explosion –With multiple, structured interfaces This problem cannot be fully simulated with computers –Too big, too complex, high Reynolds number NIF can do a very relevant experiment –Also can do transition to turbulence Preliminary design-related simulations At Michigan and LLNL –(Grosskopf) (Miles) Builds on experiments at Omega National Ignition Facility

Page January NNSA We create and study driven radiative shocks 10 drive beams Strike Be disk Xe filled tube Laser beams launch Be piston into Xe or Ar gas at > 100 km/s Piston drives a planar shock Radiography detects dense xenon Gold grid provides spatial fiducial Parameters –10 15 W/cm 2 –0.35 µm light –1 ns pulse –600 µm tube dia. Grid Target: Mike Grosskopf, Donna Marion, Mark Taylor

Page January NNSA We have radiographic images of these radiative shocks Average velocity 140 km/sec from t = 0 to 14.6 ns from laser firing Two Phys. Plasmas papers Exploration of structure will be a next theme gold grid 63 µm Shot shock target wall Data and analysis: Amy Reighard

Page January NNSA Advanced diagnostics will measure much more Thomson scattering Collaboration with Dustin Froula and Siegfreid Glenzer of LLNL Target: Trisha Donajkowski, Mike Grosskopf, Donna Marion Design: Amy Reighard Data and analysis: Amy Reighard With Dustin Froula Target Data Fitting to data gives –110 km/s fluid velocity –ZT e = 12 x 300 eV –T e ≤ T i ≤ 500 eV Paper in prep. for Phys. Rev. Lett.

Page January NNSA We collaborate very extensively One of our shots at the Omega laser Collaborators: LLNL – Remington, Robey, Miles, Edwards, Hansen, Froula, others LLE/Rochester – Knauer, Boehly, Frank Arizona – Arnett Chicago – Plewa, Hearn, Meakin Stony Brook – Glimm, Zhang, Swesty NRL – Aglitskiy, Weaver France – Bouquet, Koenig, Michaut, Busquet Rochester – Frank Texas – Ditmire

Page January NNSA Some highlights of the past year Target innovations enabled completion of data set on Rayleigh-Taylor spike penetration Moving toward advanced diagnostics of radiative shocks Amy Reighard defended her Ph.D. Published the first graduate text in High Energy Density Physics