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The Wisconsin Plasma Astrophysics Laboratory

  • C. B. Forest (a1), K. Flanagan (a1), M. Brookhart (a1), M. Clark (a1), C. M. Cooper (a1), V. Désangles (a2), J. Egedal (a1), D. Endrizzi (a1), I. V. Khalzov (a3), H. Li (a4), M. Miesch (a5), J. Milhone (a1), M. Nornberg (a1), J. Olson (a1), E. Peterson (a1), F. Roesler (a1), A. Schekochihin (a6) (a7), O. Schmitz (a1), R. Siller (a1), A. Spitkovsky (a8), A. Stemo (a1), J. Wallace (a1), D. Weisberg (a1) and E. Zweibel (a1)...


The Wisconsin Plasma Astrophysics Laboratory (WiPAL) is a flexible user facility designed to study a range of astrophysically relevant plasma processes as well as novel geometries that mimic astrophysical systems. A multi-cusp magnetic bucket constructed from strong samarium cobalt permanent magnets now confines a $10~\text{m}^{3}$ , fully ionized, magnetic-field-free plasma in a spherical geometry. Plasma parameters of $T_{e}\approx 5$ to $20~\text{eV}$ and $n_{e}\approx 10^{11}$ to $5\times 10^{12}~\text{cm}^{-3}$ provide an ideal testbed for a range of astrophysical experiments, including self-exciting dynamos, collisionless magnetic reconnection, jet stability, stellar winds and more. This article describes the capabilities of WiPAL, along with several experiments, in both operating and planning stages, that illustrate the range of possibilities for future users.


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Alexakis, A., Mininni, P. D. & Pouquet, A. 2006 On the inverse cascade of magnetic helicity. Astrophys. J. 640 (1), 335.
Barnes, S. A. 2007 Ages for illustrative field stars using gyrochronology: viability, limitations, and errors. Astrophys. J. 669, 11671189.
Battaglia, D. J., Bongard, M. W., Fonck, R. J., Redd, A. J. & Sontag, A. C. 2009 Tokamak startup using point-source dc helicity injection. Phys. Rev. Lett. 102 (22), 225003.
Blackman, E. G. & Field, G. B. 2001 How astrophysical mean field dynamos can circumvent existing quenching constraints. Phys. Plasmas 8 (5), 24072414.
Blackman, E. G. & Ji, H. 2006 Laboratory plasma dynamos, astrophysical dynamos and magnetic helicity evolution. Mon. Not. R. Astron. Soc. 369 (4), 18371848.
Blandford, R. D. & Payne, D. G. 1982 Hydromagnetic flows from accretion discs and the production of radio jets. Mon. Not. R. Astron. Soc. 199, 883903.
Boffard, J. B., Jung, R. O., Lin, C. C. & Wendt, A. E. 2010 Optical emission measurements of electron energy distributions in low-pressure argon inductively coupled plasmas. Plasma Sources Sci. Technol. 19 (6), 065001.
Brandenburg, A. & Sandin, C. 2004 Catastrophic alpha quenching alleviated by helicity flux and shear. Astron. Astrophys. 427, 1321.
Christensen-Dalsgaard, J. 2002 Helioseismology. Rev. Mod. Phys. 74 (4), 1073.
Coakley, M. M., Roesler, F. L., Reynolds, R. J. & Nossal, S. 1996 Fabry–Perot CCD annular-summing spectroscopy: study and implementation for aeronomy applications. Appl. Opt. 35 (33), 64796493.
Cooper, C. M., Wallace, J., Brookhart, M., Clark, M., Collins, C., Ding, W. X., Flanagan, K., Khalzov, I., Li, Y., Milhone, J., Nornberg, M., Nonn, P., Weisberg, D., Whyte, D. G., Zweibel, E. & Forest, C. B. 2014 The Madison Plasma Dynamo Experiment: a facility for studying laboratory plasma astrophysics. Phys. Plasmas 21, 013505.
Cothran, C. D., Brown, M. R., Gray, T., Schaffer, M. J. & Marklin, G. 2009 Observation of a helical self-organized state in a compact toroidal plasma. Phys. Rev. Lett. 103 (21), 215002.
Daughton, W. & Roytershteyn, V. 2012 Emerging parameter space map of magnetic reconnection in collisional and kinetic regimes. Space Sci. Rev. 172 (1–4), 271282.
Deng, B. H., Brower, D. L., Ding, W. X., Wyman, M. D., Chapman, B. E. & Sarff, J. S. 2006 High-speed three-wave polarimeter–interferometer diagnostic for Madison symmetric torus. Rev. Sci. Instrum. 77 (10), 10F108.
Deng, C., Brower, D. L., Ding, W. X., Almagri, A. F., Anderson, D. T., Anderson, F. S. B., Gerhardt, S. P., Probert, P. & Talmadge, J. N. 2003 First results from the multichannel interferometer system on HSX. Rev. Sci. Instrum. 74 (3), 16251628.
ud Doula, A., Townsend, R. H. D. & Owocki, S. P. 2006 Centrifugal breakout of magnetically confined line-driven stellar winds. Astrophys. J. Lett. 640 (2), L191.
Egedal, J., Le, A. & Daughton, W. 2013 A review of pressure anisotropy caused by electron trapping in collisionless plasma, and its implications for magnetic reconnection. Phys. Plasmas 20 (2013), 061201.
Frisch, U., Pouquet, A., Léorat, J. & Mazure, A. 1975 Possibility of an inverse cascade of magnetic helicity in magnetohydrodynamic turbulence. J. Fluid Mech. 68 (4), 769778.
Gallet, B., Aumaître, S., Boisson, J., Daviaud, F., Dubrulle, B., Bonnefoy, N., Bourgoin, M., Odier, P., Pinton, J.-F., Plihon, N., Verhille, G., Fauve, S. & Pétrélis, F. 2012 Experimental observation of spatially localized dynamo magnetic fields. Phys. Rev. Lett. 108 (14), 144501.
Gough, D. O. & McIntyre, M. E. 1998 Inevitability of a magnetic field in the sun’s radiative interior. Nature 394, 755757.
Gray, T., Lukin, V. S., Brown, M. R. & Cothran, C. D. 2010 Three-dimensional reconnection and relaxation of merging spheromak plasmas. Phys. Plasmas 17 (10), 102106.
Hershkowitz, N., Leung, K. N. & Romesser, T. 1975 Plasma leakage through a low- ${\it\beta}$ line cusp. Phys. Rev. Lett. 35, 277.
Hsu, S. C. & Bellan, P. M. 2002 A laboratory plasma experiment for studying magnetic dynamics of accretion discs and jets. Mon. Not. R. Astron. Soc. 334 (2), 257261.
Hsu, S. C. & Bellan, P. M. 2003 Experimental identification of the kink instability as a poloidal flux amplification mechanism for coaxial gun spheromak formation. Phys. Rev. Lett. 90 (21), 14.
Hubbard, A. & Brandenburg, A. 2012 Catastrophic quenching in ${\it\alpha}{\it\Omega}$ dynamos revisited. Astrophys. J. 748 (1), 51.
Hubble, A. A., Barnat, E. V., Weatherford, B. R. & Foster, J. E. 2014 The electron spatial distribution and leak width in a magnetic cusp. Plasma Sources Sci. Technol. 23 (2), 2200122006.
Hwang, K. J., Goldstein, M. L., Wendel, D. E., Fazakerley, A. N. & Gurgiolo, C. 2013 Cluster observations near reconnection X lines in Earth’s magnetotail current sheet. J. Geophys. Res. 118 (February), 41994209.
Iskakov, A. B., Schekochihin, A. A., Cowley, S. C., McWilliams, J. C. & Proctor, M. R. E. 2007 Numerical demonstration of fluctuation dynamo at low magnetic Prandtl numbers. Phys. Rev. Lett. 98 (2), 208501.
Jarboe, T. R. 2005 The spheromak confinement device. Phys. Plasmas 12 (5), 058103.
Ji, H. 1999 Turbulent dynamos and magnetic helicity. Phys. Rev. Lett. 83 (16), 3198.
Ji, H. & Daughton, W. 2011 Phase diagram for magnetic reconnection in heliophysical, astrophysical, and laboratory plasmas. Phys. Plasmas 18 (11), 111207.
Käpylä, P. J., Korpi, M. J. & Brandenburg, A. 2010 Open and closed boundaries in large-scale convective dynamos. Astron. Astrophys. 518, A22.
Katz, N., Collins, C., Wallace, J., Clark, M., Weisberg, D., Jara-Almonte, J., Reese, I., Whal, C. & Forest, C. B. 2012 Magnetic bucket for rotating unmagnetized plasma. Rev. Sci. Instrum. 83, 063502.
Khalzov, I. V., Brown, B. P., Cooper, C. M., Weisberg, D. B. & Forest, C. B. 2012a Optimized boundary driven flows for dynamos in a sphere. Phys. Plasmas 19, 112106.
Khalzov, I. V., Brown, B. P., Kaplan, E. J., Katz, N., Paz-Soldan, C., Rahbarnia, K., Spence, E. J. & Forest, C. B. 2012b Resistive and ferritic-wall plasma dynamos in a sphere. Phys. Plasmas 19 (10), 104501.
Khalzov, I. V., Cooper, C. M. & Forest, C. B. 2013 Fast dynamos in spherical boundary-driven flows. Phys. Rev. Lett. 111 (12), 125001.
Kusano, K. 2002 Numerical study of three-dimensional magnetohydrodynamic instability in the solar coronal magnetic arcades. Astrophys. J. 571 (1), 532539.
Lathrop, D. P. & Forest, C. B. 2011 Magnetic dynamos in the lab. Phys. Today 64 (7), 4045.
Le, A., Egedal, J., Daughton, W., Roytershteyn, V., Karimabadi, H. & Forest, C. 2015 Transition in electron physics of magnetic reconnection in weakly collisional plasma. J. Plasma Phys. 81, 305810108.
Li, H., Lapenta, G., Finn, J. M., Li, S. & Colgate, S. A. 2006 Modeling the large scale structures of astrophysical jets in the magnetically dominated limit. Astrophys. J. 643 (1), 92100.
Li, H., Lovelace, R. V. E., Finn, J. M. & Colgate, S. A. 2001 Magnetic helix formation driven by Keplerian disk rotation in an external plasma pressure: the initial expansion stage. Astrophys. J. 561 (2), 915923.
Liu, Y., Hoeksema, J. T., Bobra, M., Hayashi, K., Schuck, P. W. & Sun, X. 2014 Magnetic helicity in emerging solar active regions. Astrophys. J. 785 (1), 13.
Lovelace, R. V. E. 1976 Dynamo model of double radio sources. Nature 262, 649652.
Lynden-Bell, D. 2003 On why discs generate magnetic towers and collimate jets. Mon. Not. R. Astron. Soc. 341, 13601372.
MacGregor, K. B. & Charbonneau, P. 1999 Angular momentum transport in magnetized stellar radiative zones. IV. Ferraro’s theorem and the solar tachocline. Astrophys. J. 519, 911917.
Malik, S. M., Sridharan, K., Fetherston, R. P., Chen, A. & Conrad, J. R. 1994 Overview of plasma source ion implantation research at University of Wisconsin–Madison. J. Vac. Sci. Technol. B 12 (2), 843849.
Matt, S. P., Brun, A. S., Baraffe, I., Bouvier, J. & Chabrier, G. 2015 The mass-dependence of angular momentum evolution in sun-like stars. Astrophys. J. Lett. 799, L23 (6pp.).
Mestel, L. 1968 Magnetic braking by a stellar wind. Mon. Not. R. Astron. Soc. 138 (3), 359391.
Miesch, M. S. & Hindman, B. W. 2011 Gyroscopic pumping in the solar near-surface shear layer. Astrophys. J. 743, 79 (25pp.).
Monchaux, R., Berhanu, M., Aumaître, S., Chiffaudel, A., Daviaud, F., Dubrulle, B., Ravelet, F., Fauve, S., Mordant, N., Pétrélis, F., Bourgoin, M., Odier, P., Pinton, J.-F., Plihon, N. & Volk, R. 2009 The Von Kármán sodium experiment: turbulent dynamical dynamos. Phys. Fluids 21 (3), 035108.
Monchaux, R., Berhanu, M., Bourgoin, M., Moulin, M., Odier, P., Pinton, J.-F., Volk, R., Fauve, S., Mordant, N., Pétrélis, F., Chiffaudel, A., Daviaud, F., Dubrulle, B., Gasquet, C., Marié, L. & Ravelet, F. 2007 Generation of a magnetic field by dynamo action in a turbulent flow of liquid sodium. Phys. Rev. Lett. 98 (4), 044502.
Moser, A. L. & Bellan, P. M. 2012 Magnetic reconnection from a multiscale instability cascade. Nature 482 (7385), 379381.
Pevtsov, A. A., Berger, M. A., Nindos, A., Norton, A. A. & van Driel-Gesztelyi, L. 2014 Magnetic helicity, tilt, and twist. Space Sci. Rev. 186 (1), 285324.
Philippov, A. A. & Spitkovsky, A. 2014 Ab initio pulsar magnetosphere: three-dimensional particle-in-cell simulations of axisymmetric pulsars. Astrophys. J. Lett. 785 (2), L33.
Priest, E. & Forbes, T. 2000 Magnetic Reconnection. Cambridge University Press.
Rafikov, R. R. & Kulsrud, R. M. 2000 Magnetic flux expulsion in powerful superbubble explosions and the ${\it\alpha}$ ${\it\Omega}$ dynamo. Mon. Not. R. Astron. Soc. 314 (4), 839848.
Raman, R., Jarboe, T. R., Nelson, B. A., Izzo, V. A., O’Neill, R. G., Redd, A. J. & Smith, R. J. 2003 Demonstration of plasma startup by coaxial helicity injection. Phys. Rev. Lett. 90 (7), 075005.
Raman, R., Mueller, D., Nelson, B. A., Jarboe, T. R., Gerhardt, S., Kugel, H. W., LeBlanc, B., Maingi, R., Menard, J., Ono, M., Paul, S., Roquemore, L., Sabbagh, S., Soukhanovskii, V.& NSTX Research Team 2010 Demonstration of tokamak ohmic flux saving by transient coaxial helicity injection in the national spherical torus experiment. Phys. Rev. Lett. 104 (9), 095003.
Rust, D. M. 2002 Helicity build-up and the role of CMEs. In American Astronomical Society Meeting Abstracts #200, Bulletin of the American Astronomical Society, vol. 34, p. 751;
Schekochihin, A. A., Cowley, S. C., Taylor, S. F., Maron, J. L. & McWilliams, J. C. 2004 Simulations of small-scale turbulent dynamo. Astrophys. J. 612, 276.
Schmitz, O., Beigman, I. L., Vainshtein, L. A., Schweer, B., Kantor, M., Pospieszczyk, A., Xu, Y., Krychowiak, M., Lehnen, M., Samm, U., Unterberg, B.& the TEXTOR team 2008 Status of electron temperature and density measurement with beam emission spectroscopy on thermal helium at textor. Plasma Phys. Control. Fusion 50 (11), 115004.
Sengupta, A. 2009 Magnetic confinement in a ring-cusp ion thruster discharge plasma. J. Appl. Phys. 105 (9), 093303.
Spence, E., Reuter, K. & Forest, C. B. 2009 Numerical simulations of a spherical plasma dynamo experiment. Astrophys. J. 700, 470478.
Spiegel, E. A. & Zahn, J.-P. 1992 The solar tachocline. Astron. Astrophys. 265, 106114.
Spitkovsky, A. 2006 Time-dependent force-free pulsar magnetospheres: axisymmetric and oblique rotators. Astrophys. J. Lett. 648 (1), L51.
Spruit, H. C. 2010 Theory of magnetically powered jets. In The Jet Paradigm (ed. Belloni, T.), pp. 233263. Springer.
Stirling, W. L., Ryan, P. M., Tsai, C. C. & Leung, K. N. 1979 Magnetic multipole line-cusp plasma generator for neutral beam injectors. Rev. Sci. Instrum. 50 (1), 102108.
Taylor, J. B. 1986 Relaxation and magnetic reconnection in plasmas. Rev. Mod. Phys. 58 (3), 741.
Thompson, M. J.2014 Solar physics: surface waves and helioseismology.
Thompson, M. J., Christensen-Dalsgaard, J., Miesch, M. S. & Toomre, J. 2003 The internal rotation of the Sun. Annu. Rev. Astron. Astrophys. 41, 599643.
Townsend, R. H. D., Rivinius, T., Rowe, J. F., Moffat, A. F. J., Matthews, J. M., Bohlender, D., Neiner, C., Telting, J. H., Guenther, D. B., Kallinger, T., Kuschnig, R., Rucinski, S. M., Sasselov, D. & Weiss, W. W. 2013 MOST observations of Ori E: challenging the centrifugal breakout narrative. Astrophys. J. 769 (1), 33.
Vishniac, E. T. & Cho, J. 2001 Magnetic helicity conservation and astrophysical dynamos. Astrophys. J. 550 (2), 752760.
Wang, S., Wendt, A. E., Boffard, J. B., Lin, C. C., Radovanov, S. & Persing, H. 2013 Noninvasive, real-time measurements of plasma parameters via optical emission spectroscopy. J. Vac. Sci. Technol. A 31 (2), 021303.
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The Wisconsin Plasma Astrophysics Laboratory

  • C. B. Forest (a1), K. Flanagan (a1), M. Brookhart (a1), M. Clark (a1), C. M. Cooper (a1), V. Désangles (a2), J. Egedal (a1), D. Endrizzi (a1), I. V. Khalzov (a3), H. Li (a4), M. Miesch (a5), J. Milhone (a1), M. Nornberg (a1), J. Olson (a1), E. Peterson (a1), F. Roesler (a1), A. Schekochihin (a6) (a7), O. Schmitz (a1), R. Siller (a1), A. Spitkovsky (a8), A. Stemo (a1), J. Wallace (a1), D. Weisberg (a1) and E. Zweibel (a1)...


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