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Title: The Mass Multiplet in Penning Trap Ion Cyclotron Resonance Mass Spectroscopy

Abstract

A model for the behavior of closely spaced masses the “mass multiplet” –in a Penning trap mass spectrometer is developed. The model shows how these species separate from each other (or not) following resonant excitation. Quantitative criteria for mass separation are developed. More surprisingly, the model shows the species tend to drift to different mean cyclotron radiu. This latter effect undoubtedly plays a role in the abundance determinations in Penning trap mass spectrometers.

Authors:
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
907933
Report Number(s):
PNNL-SA-47736
Journal ID: ISSN 0021-8979; JAPIAU; KP1704020; TRN: US0703355
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics, 101(2):Art. No. 024919; Journal Volume: 101; Journal Issue: 2
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ABUNDANCE; CYCLOTRONS; EXCITATION; ION CYCLOTRON-RESONANCE; MASS SPECTROMETERS; MASS SPECTROSCOPY; MULTIPLETS

Citation Formats

Barlow, Stephan E. The Mass Multiplet in Penning Trap Ion Cyclotron Resonance Mass Spectroscopy. United States: N. p., 2007. Web. doi:10.1063/1.2397382.
Barlow, Stephan E. The Mass Multiplet in Penning Trap Ion Cyclotron Resonance Mass Spectroscopy. United States. doi:10.1063/1.2397382.
Barlow, Stephan E. Mon . "The Mass Multiplet in Penning Trap Ion Cyclotron Resonance Mass Spectroscopy". United States. doi:10.1063/1.2397382.
@article{osti_907933,
title = {The Mass Multiplet in Penning Trap Ion Cyclotron Resonance Mass Spectroscopy},
author = {Barlow, Stephan E.},
abstractNote = {A model for the behavior of closely spaced masses the “mass multiplet” –in a Penning trap mass spectrometer is developed. The model shows how these species separate from each other (or not) following resonant excitation. Quantitative criteria for mass separation are developed. More surprisingly, the model shows the species tend to drift to different mean cyclotron radiu. This latter effect undoubtedly plays a role in the abundance determinations in Penning trap mass spectrometers.},
doi = {10.1063/1.2397382},
journal = {Journal of Applied Physics, 101(2):Art. No. 024919},
number = 2,
volume = 101,
place = {United States},
year = {Mon Jan 15 00:00:00 EST 2007},
month = {Mon Jan 15 00:00:00 EST 2007}
}
  • Penning trap mass measurements of the super-allowed {beta} emitter {sup 38}Ca and of {sup 37}Ca have been performed using the low-energy beam and ion trap facility at the coupled cyclotron facility of the National Superconducting Cyclotron Laboratory. Both isotopes were produced by fast-beam fragmentation and in-flight separation. The mass of {sup 38}Ca (T{sub 1/2}=440 ms) was determined with a precision of {delta}m=280 eV, corresponding to a relative mass uncertainty of {delta}m/m{approx_equal}8x10{sup -9}. A mass excess value of ME =-22508.52(28) was obtained. {sup 38}Ca is a 0{sup +}{yields}0{sup +} emitter, and the improved mass value makes it a new candidate formore » testing the conserved vector current hypothesis. For {sup 37}Ca (T{sub 1/2}=180 ms), a mass excess value of ME =-13135.7(1.4) was measured. Using the quadratic form of the isobaric mass multiplet equation and the improved {sup 37}Ca mass value, a precise prediction of the excitation energy of the {sup 37}Ar isobaric analog state was obtained.« less
  • Off-axis ion injection into an FT-ICR ion trap is desirable for capturing ions from a continuously generated beam (e.g., electrospray). A conventional {bold E{times}B} (Wien) filter focuses ions of a {ital single} velocity (independent of mass). Here we show that by segmenting opposed flat electrodes into small sections, the electric field may be tailored to produce well-focused ion trajectories over a wide range of ion velocity and mass-to-charge ratio, {ital m}/{ital z}. In the limit of infinitely extended deflector electrodes, small {ital m}/{ital z}, and/or high {bold B}, ion trajectories vary as powers or roots of distance. {copyright} {ital 1996more » American Institute of Physics.}« less
  • A new collision-induced dissociation (CID) technique based on broadband tailored noise waveform (TNW) excitation of ions stored in a linear ion trap has been developed. In comparison with the conventional sustained off-resonance irradiation (SORI) CID method commonly used in Fourier transform ion cyclotron resonance mass spectrometry, this MS/MS technique increases throughput by eliminating the long pump-down delay associated with gas introduction into the high vacuum ICR cell region. In addition, the TNW-CID method speeds spectrum acquisition since it does not require Fourier transformation, calculation of resonant frequencies and generation of the excitation waveforms. We demonstrate TNW-CID coupled with on-line capillarymore » reverse phase liquid chromatography separations for identification of peptides. The experimental results are compared with data obtained using conventional quadrupole ion trap MS/MS and SORI-CID MS/MS in an ICR cell.« less
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