Nonlinear Effects in Cosmic Ray Transport Theory PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Nonlinear Effects in Cosmic Ray Transport Theory PDF full book. Access full book title Nonlinear Effects in Cosmic Ray Transport Theory by Andreas Shalchi. Download full books in PDF and EPUB format.
Author: Andreas Shalchi
Publisher:
ISBN:
Category :
Languages : en
Pages : 172
Get Book Here
Book Description
Author: Andreas Shalchi
Publisher:
ISBN:
Category :
Languages : en
Pages : 172
Get Book Here
Book Description
Author: Andreas Shalchi
Publisher: Springer Science & Business Media
ISBN: 3642003095
Category : Science
Languages : en
Pages : 210
Get Book Here
Book Description
If charged particles move through the interplanetary or interstellar medium, they interact with a large-scale magnetic ?eld such as the magnetic ?eld of the Sun or the Galactic magnetic ?eld. As these background ?elds are usually nearly constant in time and space, they can be approximated by a homogeneous ?eld. If there are no additional ?elds, the particle trajectory is a perfect helix along which the par- cle moves at a constant speed. In reality, however, there are turbulent electric and magnetic?elds dueto the interstellaror solar wind plasma. These ?elds lead to sc- tering of the cosmic rays parallel and perpendicular to the background ?eld. These scattering effects, which usually are of diffusive nature, can be described by s- tial diffusion coef?cients or, alternatively, by mean free paths. The knowledge of these parameters is essential for describing cosmic ray propagation as well as d- fusive shock acceleration. The latter process is responsible for the high cosmic ray energies that have been observed. The layout of this book is as follows. In Chap. 1, the general physical scenario is presented. We discuss fundamental processes such as cosmic ray propagation and acceleration in different systems such as the solar system or the interst- lar space. These processes are a consequence of the interaction between charged cosmic particles and an astrophysical plasma (turbulence). The properties of such plasmas are therefore the subject of Chap. 2.
Author: Andreas Shalchi
Publisher:
ISBN:
Category :
Languages : en
Pages : 172
Get Book Here
Book Description
Author: Thomas Joseph Birmingham
Publisher:
ISBN:
Category : Cosmic rays
Languages : en
Pages : 34
Get Book Here
Book Description
Topics discussed and summarized are: cosmic ray measurements as related to diffusion theory; quasi-linear theory, nonlinear theory, and computer simulation of cosmic ray pitch-angle diffusion; and magnetic field fluctuation measurements as related to diffusion theory.
Author: Judy L. Shinn
Publisher:
ISBN:
Category : Cross sections (Nuclear physics)
Languages : en
Pages : 26
Get Book Here
Book Description
Author: Evan Mitchell Heintz
Publisher:
ISBN:
Category :
Languages : en
Pages : 0
Get Book Here
Book Description
Cosmic rays play a major role in the stability and evolution of galaxies. While they have a fairly small density inside galaxies, their energy density is comparable to the thermal gas and magnetic fields. We now believe that cosmic rays play a major role in galactic and interstellar dynamics, including helping to drive galactic outflows, modify the galaxy's interstellar chemistry, and form large-scale structures. To understand the process of how cosmic rays do this, their microscale interactions with the gas and magnetic fields must be accurate so that their macroscale effects can reproduce observations. Our work in this thesis specifically focuses on how different models of cosmic ray transport change these interactions and their effects. Through the combined approach of analytical solutions and numerical simulations, this thesis aims to better understand how cosmic ray transport affects the stability of the interstellar medium and drive galactic outflows. We begin in Chapter 2 with a linear stability analysis of the Parker instability, a Rayleigh-Taylor like instability with the thermal gas supported against gravity by magnetic fields and cosmic rays. We model three different cosmic ray transport models and find that the model where cosmic rays stream relative to the thermal gas most greatly enhances the instability due to the heating of the thermal gas by cosmic rays scattering off of magnetic fluctuations. We continue with the Parker instability in Chapter 3 where we add radiative cooling to the system and then run numerical simulations with a smooth gravitational potential in 2D and 3D to better understand the nonlinear evolution of the instability in a more realistic environment. When radiative cooling is added, we find it enhances the instability when cosmic rays are locked to the thermal gas while it dampens the instability when cosmic ray streaming is the primary mode of transport. In our MHD simulations, we find that both cosmic ray diffusion and streaming enhance the growth of the instability due to the motion of cosmic rays out of the compressive pockets of gas in the valleys of the magnetic field. While the instability growth seems similar, however, the two transport models result in quite different phase structures of the gas, especially at the top of the Parker loops where streaming cosmic rays heat the gas. We then explore the idea of a cosmic ray Eddington limit in Chapter 4. This theory supposes that cosmic rays, through their own pressure gradient, may be able to overcome hydrostatic equilibrium and launch an outflow if star formation is vigorous enough in that galaxy. For five different galaxies and many different transport models, we find that a cosmic ray Eddington limit does exist. However, the Eddington limit often requires gas densities and/or star formation rates that are far different from typical values for galaxies. Therefore, we conclude that it is unlikely that cosmic rays themselves can reach this Eddington limit and drive a galactic wind. We finally conclude in Chapter 5 with a summary of our results and a short discussion on the future research that could be done based around our conclusions.
Author: Dastgeer Shaikh
Publisher: AIP Conference Proceedings / A
ISBN:
Category : Science
Languages : en
Pages : 454
Get Book Here
Book Description
This book contains the peer-reviewed papers presented at the Sixth Annual International Astrophysics Conference. This conference brought together a range of topics that shed light on our understanding and status of turbulence and nonlinear processes in astrophysical plasmas. Coverage in this volume includes turbulent relaxation in laboratory and space plasmas and its application to coronal flux tubes, coronal heating, and the diffusion of energetic particles.
Author: I.N. Toptygin
Publisher: Springer Science & Business Media
ISBN: 9400952570
Category : Science
Languages : en
Pages : 388
Get Book Here
Book Description
Fast particles of natural or1g1n (cosmic rays) have been used for a long time as an important source of astrophysical and geophysical information. A study of cosmic ray spectra, time variations, abundances, gradients, and anisotropy provides a wealth of data on physical conditions in the regions of cosmic ray generation as well as in the media through which cosmic rays propagate. Astrophysical aspects of cosmic ray physics have been considered in a number of monograpqs. The most detailed seems to be "The Origin of Cosmic Rays" by V. L. Ginzburg and S. 1. Syrovatskij (1964) which is, however, concerned mainly with galactic cosmic rays. The physics of the circumsolar space is discussed in this book only rather briefly. Several other monographs have been devoted mostly to the physics of the interplanetary medium and cosmic rays in interplanetary space. These include the books by Dorman (1963, 1975a, b), Parker (1963), Dorman and Miroshnichenko (1968). The present monograph differs from the above mentioned books in two main aspects: (i) It presents a unified theoretical approach to analys{ng the properties of fast particles in interplanetary space, based upon consideration of cosmic rays as a highly energetic component of the interplane~ary plasma, which makes use of the plasma physics methods to describe the behaviour of cosmic rays.
Author: Reinhard Schlickeiser
Publisher: Springer Science & Business Media
ISBN: 3662048140
Category : Science
Languages : en
Pages : 521
Get Book Here
Book Description
In the first part, the book gives an up-to-date summary of the observational data. In the second part, it deals with the kinetic description of cosmic ray plasma. The underlying diffusion-convection transport equation, which governs the coupling between cosmic rays and the background plasma, is derived and analyzed in detail. In the third part, several applications of the solutions of the transport equation are presented and how key observations in cosmic ray physics can be accounted for is demonstrated.
Author: A. Balogh
Publisher: Springer Science & Business Media
ISBN: 9780792360803
Category : Science
Languages : en
Pages : 508
Get Book Here
Book Description
This volume gives a comprehensive and integrated overview of current knowledge and understanding of corotating interaction regions (CIRs) in the solar wind. It is the result of a workshop at ISSI, where space scientists involved in the Ulysses, Pioneer, Voyager, IMP-8, Wind, and SOHO missions exchanged their data and interpretations with theorists in the fields of solar and heliospheric physics. The book provides a broad synthesis of current understanding of CIRs, which form at the interface between the fast solar wind originating in the northern and southern coronal holes and the slow solar wind that originates near and within coronal streamers surrounding the heliomagnetic equator. CIRs are the dominant structure in the heliosphere near and beyond Earth on the declining phase and near the minimum of the 11-year solar activity cycle. Particles energized at the shocks that bound CIRs at heliospheric distances beyond the orbit of Earth are the dominant energetic particle population observed in the outer heliosphere at these times. Papers included in this volume cover the subject of CIRs from their dissipation in the outer hemisphere, and include discussions of complexities associated with their evolution with distance from the Sun, their three-dimensional structure, and the myriad effects that CIRs have on energetic particles throughout the heliosphere. The book is intended to provide scientists active in space physics research with an up-to-date status report on current understanding of CIRs and their effects in the heliosphere, and also to serve the advanced graduate student with introductory material on this active field of research.
