By Topic

RELAX: An ultrasensitive, resonance ionization mass spectrometer for xenon

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 $31
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

4 Author(s)
Gilmour, J.D. ; Geology Department, Manchester University, Manchester M13 9PL, United Kingdom ; Lyon, I.C. ; Johnston, W.A. ; Turner, G.

Your organization might have access to this article on the publisher's site. To check, click on this link: 

RELAX is a resonance ionization, time‐of‐flight mass spectrometer to which a cryogenic sample concentrator has been added. This has resulted in an increase in sensitivity by a factor greater than 100. The sample concentrator consists of a localized cold spot in the ion source, onto which the sample condenses, and a heating laser to release the condensed sample into the ionization region. The lifetime against detection of a sample atom is close to 20 min, which corresponds to a count rate of 1 cps from a sample of 1000 atoms, while the mass resolution is 300 (10% peak height). Sensitivity depends on the return time of sample atoms to the cold spot (10 s) and the fraction of these atoms subsequently ionized (∼1%). The minimum sample size which can be measured is limited only by blank, which is currently 2×10-15 cc STP total xenon and isotopically atmospheric (this can be attributed to the large aliquots of xenon admitted to the instrument during development, and so may be expected to decrease with time). The precision of abundance measurements has been improved by the incorporation of pulse height discrimination and pulse counting detection for the less abundant isotopes. The design, construction, and operation of the spectrometer in its new configuration are described with particular attention to abundance extraction. The effects of the sample concentrator on ionization efficiency and discrimination are discussed in detail, as are interferences from nonresonantly ionized hydrocarbons and the means of accounting for them.

Published in:

Review of Scientific Instruments  (Volume:65 ,  Issue: 3 )