Session B9: Solar and Planetary Physics

Turbulence cascades in the solar wind

The solar wind is the one astrophysical plasma we can observe in situ in exquisite detail with many spacecraft in it. It is clear that turbulence in the magnetic field is what makes this collisionless plasma act more-or-less like a simple fluid. Also, that the magnetic turbulence couples superthermal ions to the main ``fluid'' allowing them to feel the flow and be accelerated, confined and modulated. Understanding the detailed nature and structure of the magnetic turbulence in collisionless plasma is essential to understanding particle acceleration and other aspects of their interaction with astrophysical plasmas. However, the turbulence in the magnetic field is intimately coupled to the turbulence in the plasma velocity, in what is called magnetohydrodynamic (MHD) turbulence. This work will describe recent results about MHD turbulence in the solar wind. From the fluid$+$ Maxwell equations, the interaction of the two Elsasser fields Z$^{\mathrm{\pm }}=$V$+$/- B/($\mu \rho )^{\mathrm{1/2}}$ best describes the non-linear term in the MHD equations. If either is zero, there is no cascade. In theory, the turbulent heating rate is given by the linear scaling of certain mixed third moments of fluctuations in Z$^{\mathrm{\pm }}$. Solar wind data shows the linear scaling, confirming the theory in the solar wind, but the two cascades are highly variable and tend to have opposite signs. This may be intermittency.   

On the Nature of the Corona: The Electron Affinity of Metallic Hydrogen, not Extreme Temperatures, Generates Highly Ionized Gaseous Ions in the Outer Solar Atmosphere

The gas-based Standard Solar Model (SSM) must assume that the corona is excessively hot (millions of K) in order to account for solar winds and the existence of highly ionized atoms in this region of the Sun. Conversely, within the context of the liquid metallic hydrogen solar model (LMHSM), solar winds are driven by exfoliative processes occurring within layered metallic hydrogen in the solar body. The LMHSM also advances that condensed matter is interspersed throughout the corona. This is supported by the relatively cool continuous spectrum of the K-corona which reveals that photospheric material has been ejected into, and now exists, in the outer atmosphere of the Sun. It is proposed that since condensed matter can be characterized by powerful electron affinities, that coronal material can strip adjacent gaseous atoms of their electrons. In this fashion, coronal metallic hydrogen generates highly ionized ions while at the same time helping to preserve the neutrality of the solar body, as it works to channel electrons back towards the solar surface. As such, the apparent temperature of the corona is no greater than that of the photosphere and, in fact, slightly cools with elevation in accordance with the known reddening of the K-coronal spectrum. This removes the need to heat the corona in the SSM and prevents all violations of the second law of thermodynamics.   

Kuang's Semi-Classical Formalism for Calculating Electron Capture Cross Sections: A Space- Physics Application

Accurate estimates of electron-capture cross sections at energies relevant to the modeling of the transport, acceleration, and interaction of energetic neutral atoms (ENA) in space ($\sim$ few MeV per nucleon) and especially for multi-electron ions must rely on detailed, but computationally expensive, quantum-mechanical description of the collision process. Kuang's semi-classical approach is an elegant and efficient way to arrive at these estimates. Motivated by ENA modeling efforts for apace applications, we shall briefly present this approach along with sample applications and report on current progress.   

On the Thermodynamics and other Constitutive Properties of a Class of Strongly Magnetized Matter Observed In Astrophysics

It is shown that the occurrence of magnetic field work is a consistent thermodynamic explanation of the property of anti-correlation between temperature and density of the electrons gas in a class of magnetic field dominated structures observed in the interplanetary medium. In this model, a 7 to 4 scaling ratio for magnetic-work to electron-gas-work explains the observed anomalous polytropic exponent $\gamma = 1/2$.\footnote{Sittler, E.C. Jr., L.F., Burlaga: \textit{J. Geophys. Res.,103, } 17447--17454 1998} This interpretation is built on the theoretical conjecture of a matter-state having spatial-confinement of most hadronic-elements of \textit{matter,} i.e., matter held in place by the action of what is here denominated ``\textit{super-strong}'' magnetic field, which together with the plasma it contains satisfies ideal magnetohydrodynamics.\footnote{Berdichevky, D. B., et al., \textit{Phys. Rev., }\textbf{E67}, doi:10.1103/PhysRevE.036405, 2003.} We further show that, within the resolution and sensitivity of the instrumentation used, that the assumptions made in this model are consistent with the coherence observed in changes of magnetic field and electron distribution moments for a case study, the flux-rope (FR) structure passing Earth on June 2, 1998. Here, the intervals of coherence extend in a range of 12 to 30 s for plasma data with a resolution of 3s. Further, the diamagnetic nature of this superconductive state of matter is confirmed for a case study, and an estimate of its permeability and permittivity consistent with space plasma observations made.   

Sputtering of lunar regolith by solar wind protons and heavy ions, and general aspects of potential sputtering

New simulation results for the sputtering of lunar soil surface by solar-wind protons and heavy ions will be presented. Previous simulation results showed that the sputtering process has significant effects and plays an important role in changing the surface chemical composition, setting the erosion rate and the sputtering process timescale. In this new work and in light of recent data, we briefly present some theoretical models which have been developed to describe the sputtering process and compare their results with recent calculation to investigate and differentiate the roles and the contributions of potential (or electrodynamic) sputtering from the standard (or kinetic) sputtering.   

Understanding the Martian Atmosphere-Geosphere Interactions Using Oxygen Isotopic Forensics

Recent missions to Mars have shown that the planet might have hosted liquid water based on the morphological characteristics of its lithosphere. Information about the evolution of Martian surface and atmosphere is obtained via the study of Martian meteorites. Unlike Earth, Martian geosphere does not appear to be well mixed and bulk silicates show a range of oxygen isotope anomalies from 0.3 to 0.6 0/00. In order to understand this anomaly an experiment was designed with Mars simulant, liquid water and ozone to reproduce the unique $\Delta^{17}$O isotopic value uniquely characteristic of Martian meteorites. This quantity is used as a tracer of the reaction pathways occurring on the surface of Mars. We believe that only in the presence of these three ingredients can the specific value be achieved. By simulating the chemical processes occurring on the surface of Mars, we seek to understand the interactions of Martian hydrosphere, atmosphere and geosphere. This study is unique for the advancement of cutting edge research in the evolution of planetary atmosphere and surfaces, and the search for liquid water. The oxygen triple isotopic analysis is a tool that provides us with clues for discovering the geochemical history of the red planet.   

Terrestrial Gamma Flashes at Ground and Balloon Level

Terrestrial Gamma Flashes (millisecond-duration bursts of gamma rays produced by electrons and positrons accelerated by the electric fields accompanying lightning) have been observed by satellite detectors since the BATSE era. The TGF and Energetic Thunderstorm Rooftop Array (TETRA) is an array of NaI scintillators located on the campus of Louisiana State University in Baton Rouge, Louisiana. Since July 2010, TETRA has now detected 31 millisecond-scale bursts of gamma rays at ground level with energies 50 keV - 2 MeV associated with nearby ($<$ 8 km) thunderstorms. In addition to the TETRA array, we describe the plans for a balloon-borne instrument and a larger ground array.   

Lightning Detection at the Telescope Array Cosmic Ray Observatory

It is known that the electric fields measured in lightning clouds are an order of magnitude too small than the critical electric field required for dielectric breakdown of air, there are therefore unknown mechanisms at work which initiate lightning. One theory is that cosmic ray air showers can initiate lightning via a runaway breakdown process. To study this problem, 10 VHF lightning monitoring stations built by New Mexico Tech were deployed at the Telescope Array site on September 2013. If cosmic rays act as lightning initiators, then the TA surface detectors may be able to detect high energy particles from the associated air shower while the NMT lightning detectors simultaneously measure VHF radio pulses of the lightning discharges themselves. The Telescope Array is the largest cosmic ray observatory in the Northern hemisphere. Located in Millard County, Utah, it covers an area of 750 km$^2$. The VHF monitoring stations can be used to produce 3D images of the lightning strikes. Using both setups we hope to be able to investigate in detail the role of cosmic rays in lightning, or if there is any gamma ray production from lightning activity. We will discuss how a collaboration between TA, NMT and BNL can help in understanding of a long standing mysteries about lightning formation. Results of data analysis for events that were observed in coincidence between our detectors will be presented.   

Equations for the Formation and Origin of Planetary and Stellar Rotation

Planets and stars began as slowly rotating planetary and stellar cores of dense relevant material orbited by rings of relevant material such as iron in the case of planets and hydrogen for stars. The gravitational attraction of the dense cores caused the rings of relevant material to decay and tangentially collide with the slowly rotating planetary or stellar core and attach to them thereby transferring their orbital angular momentums to the cores. In this manner the rotation of the newly formed planet or star increased go it present speed. The general equation for the formation and origin of rotation of the newly formed planet or star is: $(I\omega)_{core} + (I\omega)_{ring 1} +...+ (I\omega)_{ring n}= (I\omega)_{newly formed planet or star}.$