The Abelianization of QCD Plasma Instabilities

QCD plasma instabilities appear to play an important role in the equilibration of quark-gluon plasmas in heavy-ion collisions in the theoretical limit of weak coupling (i.e. asymptotically high energy). It is important to understand what non-linear physics eventually stops the exponential growth of unstable modes. It is already known that the initial growth of plasma instabilities in QCD closely parallels that in QED. However, once the unstable modes of the gauge-fields grow large enough for non-Abelian interactions between them to become important, one might guess that the dynamics of QCD plasma instabilities and QED plasma instabilities become very different. In this paper, we give suggestive arguments that non-Abelian self-interactions between the unstable modes are ineffective at stopping instability growth, and that the growing non-Abelian gauge fields become approximately Abelian after a certain stage in their growth. This in turn suggests that understanding the development of QCD plasma instabilities in the non-linear regime may have close parallels to similar processes in traditional plasma physics. We conjecture that the physics of collisionless plasma instabilities in SU(2) and SU(3) gauge theory becomes equivalent, respectively, to (i) traditional plasma physics, which is U(1) gauge theory, and (ii) plasma physics of U(1)x U(1) gauge theory.Comment: 36 pages; 15 figures [minor changes made to text, and new figure added, to reflect published version

Solar Physics - Plasma Physics Workshop

A summary of the proceedings of a conference whose purpose was to explore plasma physics problems which arise in the study of solar physics is provided. Sessions were concerned with specific questions including the following: (1) whether the solar plasma is thermal or non-themal; (2) what spectroscopic data is required; (3) what types of magnetic field structures exist; (4) whether magnetohydrodynamic instabilities occur; (5) whether resistive or non-magnetohydrodynamic instabilities occur; (6) what mechanisms of particle acceleration have been proposed; and (7) what information is available concerning shock waves. Very few questions were answered categorically but, for each question, there was discussion concerning the observational evidence, theoretical analyses, and existing or potential laboratory and numerical experiments

Complexity and simplicity of plasmas

This paper has two main parts. The first one presents a direct path from microscopic dynamics to Debye screening, Landau damping and collisional transport. It shows there is more simplicity in microscopic plasma physics than previously thought. The second part is more subjective. It describes some difficulties in facing plasma complexity in general, suggests an inquiry about the methods used empirically to tackle complex systems, discusses the teaching of plasma physics as a physics of complexity, and proposes new directions to face the inflation of information.Comment: 13 page

CfA Plasma Talks

Notes from a series of 13 one hour (or more) lectures on Plasma Physics given to Ramesh Narayan' research group at the Harvard-Smithsonian Center for Astrophysics, between January and July 2012. Lectures 1 to 5 cover various key Plasma Physics themes. Lectures 6 to 12 mainly go over the Review Paper on "Multidimensional electron beam-plasma instabilities in the relativistic regime" [\emph{Physics of Plasmas} \textbf{17}, 120501 (2010)]. Lectures 13 talks about the so-called Biermann battery and its ability to generate magnetic fields from scratch.Comment: 58 pages, 21 figure

Plasma kinetic theory

The description of plasma using fluid model is mostly insufficient and requires the consideration of velocity distribution which leads to kinetic theory. Kinetic theory of plasma describes and predicts the condition of plasma from microscopic interactions and motions of its constituents. It provides an essential basis for an introductory course on plasma physics as well as for advanced kinetic theory. Plasma kinetics deals with the relationship between velocity and forces and the study of continua in velocity space. Plasma kinetics mathematical equations provide aid to the readers in understanding simple tools to determine the plasma dynamics and kinetics as described in this chapter. Kinetic theory provides the basics and essential introduction to plasma physics and subsequently advanced kinetic theory. Plasma waves, oscillations, frequencies, and applications are the subjects of kinetic theory. In this chapter, mathematical formulations essential for exploring plasma kinetics are compiled and described simplistically along with a precise discussion on basic plasma parameters in simple language with illustrations in some cases

Working Group Report: Heavy-Ion Physics and Quark-Gluon Plasma

This is the report of Heavy Ion Physics and Quark-Gluon Plasma at WHEPP-09 which was part of Working Group-4. Discussion and work on some aspects of Quark-Gluon Plasma believed to have created in heavy-ion collisions and in early universe are reported.Comment: 20 pages, 6 eps figures, Heavy-ion physics and QGP activity report in "IX Workshop on High Energy Physics Phenomenology (WHEPP-09)" held in Institute of Physics, Bhubaneswar, India, during January 3-14, 2006. To be published in PRAMANA - Journal of Physics (Indian Academy of Science

Physics of Quark--Gluon Plasma

In this lecture, we give a brief review of what theorists now know, understand, or guess about static and kinetic properties of quark--gluon plasma. A particular attention is payed to the problem of physical observability, i.e. the physical meaningfulness of various characteristics of $QGP$ discussed in the literature.Comment: 35 pages LaTeX, 3 Postscript figures included by epsf.sty are now fixed and printable, uses axodraw.sty included in the package. Some references added and minor stylistic changes made. Lecture at the XXIV ITEP Winter School (Snegiri, February 1996

Ultracold Neutral Plasmas

Ultracold neutral plasmas are formed by photoionizing laser-cooled atoms near the ionization threshold. Through the application of atomic physics techniques and diagnostics, these experiments stretch the boundaries of traditional neutral plasma physics. The electron temperature in these plasmas ranges from 1-1000 K and the ion temperature is around 1 K. The density can approach $10^{11}$ cm$^{-3}$. Fundamental interest stems from the possibility of creating strongly-coupled plasmas, but recombination, collective modes, and thermalization in these systems have also been studied. Optical absorption images of a strontium plasma, using the Sr$^+$ ${^2S\_{1/2}} -> {^2P\_{1/2}}$ transition at 422 nm, depict the density profile of the plasma, and probe kinetics on a 50 ns time-scale. The Doppler-broadened ion absorption spectrum measures the ion velocity distribution, which gives an accurate measure of the ion dynamics in the first microsecond after photoionization.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France

Research in plasma physics

Three aspects of barium ion cloud dynamics are discussed. First, the effect of the ratio of ion cloud conductivity to background ionospheric conductivity on the motion of barium ion clouds is investigated and compared with observations of barium ion clouds. This study led to the suggestion that the conjugate ionosphere participates in the dynamics of barium ion clouds. Second, analytic work on the deformation of ion clouds is presented. Third, a linearized stability theory was extended to include the effect of the finite extent of an ion cloud, as well as the effect of the ratio of ion cloud to ionospheric conductivities. The stability properties of a plasma with contra-streaming ion beams parallel to a magnetic field are investigated. The results are interpreted in terms of parameters appropriate for collisionless shock waves. It is found that this particular instability can be operative only if the up-stream Alfven Mach number exceeds 5.5