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14th ANNUAL INTERNATIONAL ASTROPHYSICS CONFERENCE ORAL ABSTRACTS Adhikari, The Transport of Low‐Frequency Turbulence in Astrophysical Flows. II. Solutions for the super‐Alfvenic solar wind Laxman Laxman Adhikari, University of Alabama in Huntsville, USA Gary P. Zank, University of Alabama in Huntsville, USA Roberto Bruno, INAF‐IAPS Instituto di Astrofisica e Planetologia Spaziali, Italy Daniele Telloni, INAF‐Astrophysical Observatory of Torino, Italy Peter Hunana, Center for Space Plasma and Aeronomic Research (CSPAR), USA Alexander Dosch, Center for Space Plasma and Aeronomic Research (CSPAR), USA Raffaele Marino, National Center for Atmospheric Research, USA Qiang Hu, University of Alabama in Huntsville, USA Zank et al. 2012 developed a turbulence transport model for low‐frequency incompressible magnetohydrodynamic (MHD) turbulence in inhomogeneous flows in terms of the energy corresponding to forward and backward propagating modes, the residual energy, the correlation lengths corresponding to forward and backward propagating modes, and the correlation length of the residual energy. We apply the Zank et al. model to the super‐Alfvenic solar wind i.e., |U|>>|V A |and solve the coupled equations for two cases, the first being the heliosphere from 0.29 AU to 5 AU with and without the Alfven velocity, and the second being the “entire” heliosphere from 0.29 AU to 100 AU in the absence of the Alfven velocity. The model shows that (1) shear driving is responsible for the in situ generation of backward propagating modes, (2) the inclusion of the background magnetic field modifies the transport of turbulence in the inner heliosphere, (3) the correlation lengths of forward and backward propagating modes are almost equal beyond ~30 AU, and (4) the fluctuating magnetic and kinetic energies in MHD turbulence are in approximate equipartition beyond~30 AU. A comparison of the model results with observations for the two cases shows that the model reproduces the observations quite well from 0.29 AU to 5 AU. The outer heliosphere (> 1 AU) observations are well described by the model. The temporal and latitudinal dependence of the observations makes a detailed comparison difficult but the overall trends are well captured by the models. We conclude that the results are a reasonable validation of the Zank et al. 2012 model for the super‐Alfvenic solar wind. Antiochos, Spiro The Origin of Impulsive Solar Energetic Particles Spiro K. Antiochos, NASA/GSFC, USA Sophie Masson, LESIA, Paris Observatory, France C. Richard DeVore, NASA/GSFC, USA Among the most important, but least understood forms of space weather are the so‐called Impulsive Solar Energetic Particle (SEP) events, which can be especially hazardous to deep‐space astronauts. These energetic particles are widely believed to be produced by the flare reconnection that is the primary driver of coronal mass ejections (CME) / eruptive flare events. The main difficulty with this idea is that in the standard model for a CME/flare magnetic topology, the particles should remain trapped in the closed flare loops and in the ejected plasmoid, the CME. However, flare‐accelerated particles frequently reach the Earth long before the CME does. In previous 2.5D calculations we showed how the external reconnection that is an essential element of the breakout model for CME initiation could lead to the escape of flare‐accelerated particles. The problem, however, is that in 2.5D this reconnection also tends to destroy the plasmoid, which disagrees with the observation that SEP events are often associated with well‐defined plasmoids at 1 AU, the so‐called magnetic clouds. Consequently, we have extended our calculations to a fully 3D topology that includes a multi‐polar coronal field suitable for a breakout CME/eruptive flare near a coronal hole region. We performed high‐resolution 3D MHD numerical simulations with the Adaptively Refined MHD Solver (ARMS). Our results demonstrate that the model allows for the effective escape of energetic particles from deep within an ejecting well‐defined plasmoid. We show how the complex interactions between the flare and breakout reconnections reproduce all the main observational features of CMEs/flares and impulsive SEPs. We discuss the implications of our calculations for theories of particle acceleration and for observations from the upcoming Solar Orbiter and Solar Probe Plus missions, which will measure impulsive SEPs near the Sun, thereby, mitigating propagation effects. This research was supported, in part, by the NASA SR&T and TR&T Programs. 14th ANNUAL INTERNATIONAL ASTROPHYSICS CONFERENCE ORAL ABSTRACTS Baring, Matthew Probing Acceleration at Relativistic Shocks in Blazar Jets Markus Böttcher, North‐West University, South Africa Errol J. Summerlin, NASA's Goddard Space Flight Center Acceleration at relativistic shocks is likely to be important in various astrophysical jet sources, including blazars and other radio‐loud active galaxies. An important recent development for blazar science is the ability of Fermi‐LAT data to pin down the power‐law index of the high energy portion of emission in these sources, and therefore also the index of the underlying non‐thermal particle population. This paper highlights how multiwavelength spectra including X‐ray band and Fermi data can be used to probe diffusive acceleration in relativistic, oblique, MHD shocks in blazar jets. The spectral index of the non‐thermal particle distributions resulting from Monte Carlo simulations of shock acceleration, and the fraction of thermal particles accelerated to non‐thermal energies, depend sensitively on the particles' mean free path scale, and also on the mean magnetic field obliquity to the shock normal. We investigate the radiative synchrotron/Compton signatures of the resulting thermal and non‐thermal particle distributions. Important constraints on the frequency of particle scattering and the level of field turbulence are identified for the blazars AO 0235+164 and Mrk 501. The possible interpretation that turbulence levels decline with remoteness from jet shocks, and a significant role for non‐gyroresonant diffusion, are discussed, and analogies to heliospheric conditions are drawn. Bellan, Paul MHD Jets P. M. Bellan, Caltech, USA X. Zhai, Caltech, USA K. B. Chai, Caltech, USA Dynamics relevant to solar and astrophysical plasmas is being investigated using lab experiments governed by the same physics, having the same topology, but much smaller time and space scales. Plasma dynamics is tracked using high speed imaging (movies) that by resolving sub‐Alfven time scales reveal unexpected, new phenomena. In contrast to models which neglect flows and pressure gradients, the movies show that a highly collimated MHD‐driven plasma flow is the outstanding feature of the dynamics. This flow is effectively a lab version of an astrophysical jet. The jet velocity is in good agreement with an MHD acceleration model [1]. Axial stagnation of the jet compresses embedded azimuthal magnetic flux and results in jet self‐collimation. Jets kink when they breach the Kruskal‐Shafranov stability limit. The acceleration of a sufficiently strong kink provides an effective gravity that can provide the environment for a spontaneously developing fine‐scale, extremely fast Rayleigh‐Taylor instability that erodes the current channel to be smaller than the ion skin depth [2]. This cascade from the ideal MHD kink scale to the non‐MHD ion skin depth scale can result in a fast magnetic reconnection whereby the jet breaks off from its source electrode [2] and particles are energized. A 3D numerical MHD code [3] has quantitatively reproduced the acceleration, collimation, and dynamically changing density/pressure/magnetic profile of the jet. Supported by USDOE [1] D. Kumar and P. M. Bellan, Phys. Rev. Letters 103, Art. No. 105003 (2009) [2] A. L. Moser and P. M. Bellan, Nature 482, 379 (2012) [3] X. Zhai, H. Li, P. M. Bellan, and S. T. Li, Astrophys. J. 291, Art. No. 40 (2014) 14th ANNUAL INTERNATIONAL ASTROPHYSICS CONFERENCE ORAL ABSTRACTS Bucik, Radoslav Long‐Lived Energetic Particle Source Regions on the Sun R. Bucik, MPS, Germany D. E. Innes, MPS, Germany N.‐H. Chen, MPS, Germany G. M. Mason, APL/JHU, USA R. Gomez‐Herrero, SRG/UAH, Spain M. E. Wiedenbeck, JPL/Caltech, USA Discovered more than 40 years ago, impulsive solar energetic particle (SEP) events are still poorly understood. The enormous abundance enhancement of the rare 3He isotope is the most striking feature of these events, though large enhancements in heavy and ultra‐heavy nuclei are also observed. Recurrent 3He‐rich SEPs in impulsive events have only been observed for limited time periods, mostly about one day which is typically the time that a single stationary spacecraft is magnetically connected to the source active regions on the Sun. With the launch of the two STEREO spacecraft we now have the possibility of an uninterrupted view and a longer connection time to solar active regions. We present the first report of source regions with repeated 3He‐rich SEP emissions for relatively long time periods, lasting at least a quarter of a solar rotation. We found that recurrent 3He‐rich SEPs in the long‐lived sources occur after the emergence of magnetic flux. These new observations reveal that physical conditions for particle acceleration and escape from the Sun can persist for a long time, perhaps for the entire lifetime of an active region. Buechner, Joerg Electron Energization in the Solar Corona Joerg Buechner, Max‐Planck‐Institute for Solar System Research Goettingen, Germany Patricio Munoz, Max‐Planck‐Institute for Solar System Research, Goettingen, Germany In the solar corona electrons are accelerated to high energies that cause soft and hard X‐rays by Bremsstrahlung in the chromosphere. Since it is not clear whether slow mode shocks are formed at all in the course of coronal magnetic reconnection we discuss the formation of potential structures (double layers ) in strong coronal current concentrations as well as magnetic reconnection in the strong magnetic (“guide”) field of the corona as two possible ways to reach these energies and demonstrate these mechanisms by means of numerical simulations for the plasma conditions of the solar corona.