We are inviting IDEALS users, both people looking for materials in IDEALS and those who want to deposit their work, to give us feedback on improving this service through an interview. Participants will receive a $20 VISA gift card. Please sign up via webform.

Files in this item



application/pdfSU-THESIS-2016.pdf (1MB)
(no description provided)PDF


Title:Supersonic cooling of short-lived molecular states in a pulsed microcavity plasma jet
Author(s):Su, Rui
Advisor(s):Eden, James G
Department / Program:Electrical & Computer Eng
Discipline:Electrical & Computer Engr
Degree Granting Institution:University of Illinois at Urbana-Champaign
supersonic cooling
molecular spectroscopy
Abstract:Electronic states of helium diners having potential energy > 24 eV and radiative lifetimes as short as 19 ns have been generated in a micro-plasma jet at super-atmospheric pressure and rotationally cooled by supersonic expansion. Spatial-temporal spectrograms of d^3Σ+u→(b^3)π_g (v', v") = (0, 0) emission are obtained, which contain the information about the dynamic cooling process during the molecular beam expansion. Analysis shows the spatial-temporal evolution of the rotational temperature to be a damped sinusoid that reaches a minimum value of 100 K, which is attributed to the reflection of electrons from a virtual cathode located downstream of the jet nozzle. Data fitting to the damped sinusoid function yields a spatially-averaged electron density of 10^8 cm^(-3). The experimental setup has the potential to be used in exploration of the spectroscopy and plasma dynamics in various gas molecules.
Issue Date:2016-04-05
Rights Information:Copyright 2016 Rui Su
Date Available in IDEALS:2016-07-07
Date Deposited:2016-05

This item appears in the following Collection(s)

Item Statistics