Cart (Loading....) | Create Account
Close category search window
 

Time-dependence of the electron energy distribution function in the nitrogen afterglow

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

7 Author(s)
Guerra, V. ; Centro de Fisica dos Plasmas, Inst. Superior Tecnico, Lisboa, Portugal ; Dias, F.M. ; Loureiro, J. ; Paulo Araujo Sa
more authors

In this paper, we present an investigation of the time-relaxation of the electron energy distribution function (EEDF) in the nitrogen afterglow of an ω/2π=433 MHz flowing discharge at p=3.3 torr, in a tube with inner radius R=1.9 cm. We solve the time-dependent Boltzmann equation, including the term for creation of new electrons in associative/Penning reactions, coupled to a system of rate balance equations for the heavy-particles. The EEDFs are also obtained experimentally, from second derivatives of digitized probe characteristics measured using a triple probe technique, and compared with the calculations. It is shown that an equilibrium between the vibrational distribution function of ground-state molecules N2(X1Σg+,v) and low-energy electrons is rapidly established, in times ∼10-7 s. In these early instants of the postdischarge, a dip is formed in the EEDF around 4 eV. The EEDF finally reaches a quasi-stationary state for t≳10-6 s, although the electron density still continues to decrease beyond this instant. Collisions of highly excited N2(X1Σg+,v≳35) molecules with N(4S) atoms are in the origin of a maximum in the electron density occurring downstream from the discharge at ≃2×10-2 s. These reactions create locally the metastable states N2(A3Σu+) and N2(a'1Σu-), which in turn ionize the gas in associative/Penning processes. Slow electrons remain for very long times in the postdischarge and can be involved in electron stepwise processes with energy thresholds smaller than ∼2-3 eV.

Published in:

Plasma Science, IEEE Transactions on  (Volume:31 ,  Issue: 4 )

Date of Publication:

Aug. 2003

Need Help?


IEEE Advancing Technology for Humanity About IEEE Xplore | Contact | Help | Terms of Use | Nondiscrimination Policy | Site Map | Privacy & Opting Out of Cookies

A not-for-profit organization, IEEE is the world's largest professional association for the advancement of technology.
© Copyright 2014 IEEE - All rights reserved. Use of this web site signifies your agreement to the terms and conditions.