Purdue University Purdue Links
PRIME Lab PRIME Lab Department of Physics Physics photos
Accelerator mass spectrometry of 10Be, 14C, 26Al, 36Cl, 41Ca, 129I
Introduction
 Research Using AMS For Users Personnel Ion Source Useful Links Photogallery PRIME Lab Home
AMS injector beamline
  Cassette, Rod
  Assembly
  and Drive Table

  Rabbit sample
  changer

  Cathode assembly
  with immersion lens

  Insulator

  Ionizer

  Extractor-Steerer

  Einzel lens

Ion Optics

Performance and Progress

How they move

0

» Ion Source

Performance and Progress

Child's Law

Estimated Cs+ current for varied cathode voltage at four reservoir temperatures with a fixed ionizer power of 170 W.

 

Ion Source Current

March 16th 2004

We are doing preliminary tests of the new source on a test-bed. Most of our testing utilizes reactor graphite and beryllium oxide.

Sample Material

Nominal current

(old source)

Minimum* current

(new source)

Minimum improvement factor

Reactor graphite

25 mA

55 mA

2.2

BeO

1.5 mA

4 mA

2.7

* The beam is clipped on several apertures in the test bed and currents are likely less than optimized because of poor pumping. The new injector will have larger apertures and better pumping.

 

Ion Source To-Do List

April 23th 2004

Task Result
Check Cs Focus Done-Excellent Cs focus
Check optimization of immersion lens geometry In process
Optimize pump-out rate of sample rod Problems understood and fix is in process
Validate performance of octapole steerer Done
Validate performance of einzel lens Done
Validate voltage holding capacity of cathode assembly Done - No sparking in source, output of secondary is extremely stable
Construction of steerer and first BPM assembly Done
Leak detection of steerer assembly Done - Hallelujah, it doesn't leak!
Construction of second einzel assembly Done
Construction of second BPM assembly Done
Optimization of ion source maintenance In progress
Validate reliability of sample changing Software bugs fixed, testing to commence next week
PC control of electronics with LabView Software in use but still being optimized
Construction of racks for high-voltage-deck Drawings are complete, construction of parts is nearly complete
Installation of the new ion source will commence as soon as the racks and modifications to the high-voltage-deck are completed

Purdue Rare Isotope Measurement Laboratory, Purdue University, 525 Northwestern Avenue, West Lafayette, IN 47907-2036
Telephone: (765) 494-5381  Fax: (765) 496-7228

Prof. Marc Caffee, Director  mcaffee@physics.purdue.edu  (765) 494-2586

PRIME Lab is funded by the National Science Foundation.
purdue homepage purdue search purdue maps purdue directories Copyright © 2003, Purdue University, all rights reserved. An equal access/equal opportunity university.
Purdue Disclaimer Nondiscrimination Policy apply to Physics Search Purdue map area map area visit purdue UDO