Measurement of charge exchange cross sections for highly charged xenon and thorium ions with molecular hydrogen in a Penning ion trap /
Highly charged xenon (3 5 + to 46+) and thorium (72+ to 79+)
| Main Author: | |
|---|---|
| Format: | Thesis Book |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
1995.
|
| Subjects: | |
| Online Access: | Link to OAKTrust copy http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=742745261&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | Highly charged xenon (3 5 + to 46+) and thorium (72+ to 79+) ions were produced in an Electron Beam Ion Trap (EBIT). The ions were extracted from EBIT in a short pulse. Ions of one charge state were selected using an electromagnet. The ions were recaptured at low energy in a cryogenic Penning trap (RETRAP). As the ions captured electrons from molecular hydrogen, populations of the various charge states were obtained by measuring the image currents induced by the ions on the electrodes of the trap. Data on the number of ions in each charge state vs. time were compared to theoretical rate equations in order to determine the average charge exchange rates. These rates were compared to charge exchange rates of an ion with a known charge exchange cross section (Ar11+) measured in a similar manner in order to determine the average charge exchange cross sections for the highly charged ions. The energy of interaction between the highly charged ions and hydrogen was estimated to be 4 eV in the center of mass frame. The mean charge exchange cross sections were 9 x 10-14 cm' for Xe 41+ to Xe46+ and 2x I 0-13 cm2 for Th73+ to Th 79+ Double capture was approximately. 20-25% of the total for both xenon and thorium. A fit indicated that the cross sections were approximately proportional to q 1.2 This is consistent with a linear dependence of cross section on q within the measurement uncertainties. |
|---|---|
| Item Description: | Vita. "Major Subject: Physics". |
| Physical Description: | vi, 67 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |