Observations on the ponderomotive force

D. A. Burton; R. A. Cairns; B. Ersfeld; A. Noble; S. Yoffe; D. A. Jaroszynski

doi:10.1117/12.2270542

15 May 2017 Observations on the ponderomotive force

D. A. Burton, R. A. Cairns, B. Ersfeld, A. Noble, S. Yoffe, D. A. Jaroszynski

Proceedings Volume 10234, Relativistic Plasma Waves and Particle Beams as Coherent and Incoherent Radiation Sources II; 102340G (2017) https://doi.org/10.1117/12.2270542
Event: SPIE Optics + Optoelectronics, 2017, Prague, Czech Republic

Abstract

The ponderomotive force is an important concept in plasma physics and, in particular, plays an important role in many aspects of the theory of laser plasma interactions including current concerns like wakefield acceleration and Raman amplification. The most familiar form of this gives a force on a charged particle that is proportional to the slowly varying gradient of the intensity of a high frequency electromagnetic field and directed down the intensity gradiant. For a field amplitude simply oscillating in time there is a simple derivation of this formula, but in the more general case of a travelling wave the problem is more difficult. Over the years there has been much work on this using Hamiltonian or Lagrangian averaging techniques, but little or no investigation of how well these theories work. Here we look at the very basic problem of a particle entering a region with a monotonically increasing electrostatic field amplitude and being reflected. We show that the equation of motion derived from a widely quoted ponderomotive potential only agrees with the numerically computed orbit within a restricted parameter range and that outside this range it shows features which are inconsistent with any ponderomotive potential quadratic in the field amplitude. Since the ponderomotive force plays a fundamental role in a variety of problems in plasma physics we think that it is important to point out that even in the simplest of configurations standard theories may not be accurate.

Citation Download Citation

D. A. Burton, R. A. Cairns, B. Ersfeld, A. Noble, S. Yoffe, and D. A. Jaroszynski "Observations on the ponderomotive force", Proc. SPIE 10234, Relativistic Plasma Waves and Particle Beams as Coherent and Incoherent Radiation Sources II, 102340G (15 May 2017); https://doi.org/10.1117/12.2270542

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available