CMSO Response to the PAC

1. CMSO Response to the PAC October 2011

2. Current Research .

3. CMSO Reconnection & Dynamo Experiments Reconnection Dynamo MDX (Madison Dynamo Experiment, Liquid Na) MST (Madison Symmetric Torus) MPDX (Madison Plasma Dynamo Experiment) • MST (Madison Symmetric Torus; UW) • MRX (Magnetic Reconnection Experiment; PPPL) • RWM (Rotating Wall Machine; UW) • RSX (Reconnection Scaling Experiment; LANL) • SSX (Swarthmore Spheromak Experiment)

4. CMSO Turbulence & Momentum Transport Experiments Momentum Transport Turbulence HTX (Hydrodynamic Turbulence Experiment; PPPL) MDX (Madison Dynamo Experiment) MRX (Magnetic Reconnection Experiment) MST (Madison Symmetric Torus) • MRI (Magneto-rotational Instability; PPPL) • MST (Madison Symmetric Torus) • PCX (Plasma Couette Experiment; UW)

5. Financial Breakdown (per year) • $2.4M from NSF for 3rd yr; $ .835M in subawards • 50K SSX • MRX $550K base, $355K CMSO • RWM $120K (NSF/DoE) • MDX $250K + CMSO postdoc • MPDX $2.5M/3 + CMSO grad student + CMSO postdoc • MRI/HTX $300K/yr + $238K for research at PU • MST $5.4M + $.38M CMSO • $.850M from DoE, about $.150M of which never arrived

6. Q: Roles of Studying MRI and Its Relatives in the Lab • Motivated by astrophysical MRI, Princeton MRI Experiment studies fundamental MHD physics in rotating flow.  Basic Physics • Challenges theory and simulations.  code validation • Revealed importance of boundaries on bulk flow physics.  implications for geodynamo: to be unfolded • Planning the next step at PPPL for scaling studies under numerical explorations • Shercliff layer instability (Gissinger et al. 2011) • Axisymmetric localized MRI (Petitdemange et al. 2008)

7. Questions on Capabilities of NGRX • How important is the Hall effect vs other mechanisms of fast reconnection? As we see it, very important. The Hall electric field facilitates fast reconnection in the collisionless & hybrid regimes. • How can NGRX be used to study particle acceleration & heating? Collisionless regime, multiple island mechanisms, size advantage, additional diagnostics. Shoot plasma gun into NGRX to create a shock.

8. Answers: turbulenceRe: Boldyrev/Lazarian controversy Basic MHD theory is not the only work done by the groups of Boldyrev and Lazarian* Conflicting results in basic MHD are probably overshadowing other work at this point Therefore, to move on we will •Formulate a set of matching tests to be performed •Ask each group to perform tests •Explain that if tests are not performed, work in this area will not be featured in future presentations *Other activities include Weak MHD turbulence, Polymer analog for MRI, cosmic ray/turbulence interaction, analysis techniques for astrophysical signals, turbulent reconnection, Landau fluid modeling of kinetic effects

9. Answers: TurbulenceDissipation range turbulence – where is the energy going? Background: •Theory work in this area has been performed in past (energy budget for kinetic theory of wave absorption; PIC simulations of fast wave cascade) •Strong noncollisional ion heating in MST (and weak electron cooling) is key piece of information •Experimental comparison with dissipation range theory is brand new (this year) and hasn’t progressed beyond spectral comparisons •Tools on hand, but there are limitations on manpower, particularly for modeling (PIC, realistic models for MST fluctuation structures) We agree that tracking down where the energy is going is important •We will formulate some plans for doing this, recognizing that it is a hard a problem, and may not yield conclusive answers quickly

10. Answers: turbulenceShift to kinetic theory and simulation? How does it go forward from here? Background: •Kinetic work started in DOE-funded side of laboratory studies, not as CMSO project •But once tools are available, crossover into CMSO is inevitable. This is why it was presented •It is also desirable because issues are relevant to astrophysics •Work in MHD turbulence will continue In future (next year +) •Develop MST-relevant modeling of gyroscale fluctuations and begin working on comparison with measurement data from fast Thomson, heavy ion beam probe, edge probes, FIR •Explore kinetic effects on astrophysical turbulence with gyro-Landau code

11. Answers: turbulenceMain achievements of last year; main expected results next year Last year: •Demonstration of Alfvénic regime in MST with critical balance anisotropy •Discovery that high frequency regime shows two-fluid physics •Development of general dissipation range theories for plasma turbulence •High resolution basic MHD simulations •Weak MHD turbulence - Residual energy* •CGL/gyro-Landau closures analysis of instabilities in interstellar turbulence* •Fluctuations of synchrotron radiation polarization by magnetic turbulence, comparison to interstellar turbulence* Next year •Identification/characterization of two fluid effects in MST magnetic spectrum •Development of gyrokinetic modeling capability for MST •Self consistent simulations of magnetic flux removal due to turbulent reconnection in accretion disks* •High resolution simulations of basic MHD turbulence •Analysis of dynamic alignment in solar wind with possible refinements to theory* *Astrophysics applications / potential astrophysics impact

12. Our most visible & highest impact science last year? • As you intended, this was tough – 8 research highlights for the PAC meeting; 5 for our Annual Report • Two potential game-changers: • Madison Plasma Dynamo Experiment • Reconnection Phase Diagram & plans for a next generation reconnection experiment

13. Our Greatest Weakness Insufficient clarity in our balance of basic research & applications, especially to astrophysics

14. Questions on the Future of CMSO .

15. Experiment Landscape • What experiments will operate in 2012 that were not available on 2008/2009? • Hydrodynamic Turbulence Experiment • Madison Plasma Dynamo Experiment • Plasma Couette Experiment • When will new facilities/upgrades be available? • MRX-U: could submit a proposal w. ~ 6 mo notice • MPDX : 2012

16. Question on Impulsive Dynamos We think magnetized HED experiments can contribute to our understanding of magnetized shear flow instabilities and their resulting turbulence, flow driven or forced reconnection, and magnetogenesis by the Biermann Battery. We see this work as complementary to our work on quasi-stationary flow driven, weakly magnetized dynamo experiments & strongly magnetized reconnection experiments.

17. CMSO impact on fusion development (1) • While it is clear that ITER is forcing a concentration on tokamak development, an eventual fusion reactor needs to be reliable and maintainable, with near 100% availability. The RFP (and spheromak) offers potential game-changing advantages of low-field magnets in simple topology, and large ohmic heating, eliminating complex plasma-facing auxiliary heating apparatus. Magnetic self-organization is either enabling, e.g., OFCD, or a challenge to overcome, and therefore needs to be understood. • A DOE-OFES stated priority is the development of predictive capability in fusion sciences. CMSO research has strong connections to this development, e.g., • Nearly ideal laboratories for nonlinear MHD and extended MHD for processes like tearing instability and the sawtooth internal disruption. Strong theory and modeling supports the experiments, including related tokamak research. • Emerging emphasis on microturbulence in the RFP offers a new arena to investigate the most important turbulence for tokamak plasmas, but in the low-q, high shear, and high beta limit. This is already challenging theory and gyro-kinetic codes. • Verification of stochastic transport from global tearing (and eventually microtearing?) is mature. This is important for tokamak plasmas, e.g., externally imposed stochasticity for ELM control, and for transport, e.g., ITG-driven microtearing.

18. CMSO impact on fusion development (2) • Understanding the physics of magnetic self-organization demands state-of-the-art diagnostics. These have general impact: • Advanced interferometry planned for ITER includes Faraday rotation. This is used on MST to study the RFP dynamo and momentum transport (plus measurements of the magnetic equilibrium). Future CMSO experiments will employ similar techniques. • Active spectroscopy planned for ITER includes charge exchange recombination spectroscopy and motional Stark effect, used to study magnetic self-organization processes. MST has been an instigator in driving improvement in atomic modeling for these diagnostics, in collaboration with tokamak experiments like DIII-D and JET, and the ADAS atomic database community. • In the renewal, the possible inclusion of “magnetic mediated” processes in HEDP plasmas is motivated by CMSO interests in reconnection and other processes. There is a possibility (and early favorable experimental results) that IFE fusion yield could be increased with an added magnetic confinement ingredient. The role of magnetic field is sure to grow in the development of predictive capability for HEDP/IFE. Other examples for HEDP/IFE impact are likely to arise as we develop our renewal proposal.