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Record W2024636856 · doi:10.1016/s1044-0305(00)00171-9

Observation of higher order quadrupole excitation frequencies in a linear ion trap

2000· article· en· W2024636856 on OpenAlexaff
B. A. Collings, D. J. Douglas

Bibliographic record

VenueJournal of the American Society for Mass Spectrometry · 2000
Typearticle
Languageen
FieldChemistry
TopicMass Spectrometry Techniques and Applications
Canadian institutionsUniversity of British Columbia
Fundersnot available
KeywordsChemistryAtomic physicsIonExcitationQuadrupoleQuadrupole ion trapIon trapResonance (particle physics)AmplitudeFragmentation (computing)OmegaBuffer gasAnalytical Chemistry (journal)Physics

Abstract

fetched live from OpenAlex

The resonant frequencies for quadrupole excitation of ions confined with a buffer gas in a linear quadrupole ion trap with Mathieu parameters a = 0 and q approximately 0.36 have been measured. The resonances are predicted to occur at angular frequencies omega(K)n given by omega(K)n = (omega/K)n + beta without the presence of a buffer gas where omega is the angular frequency of the trapping radio frequency, K = 1, 2, 3... is the order of the resonance calculated with perturbation theory, and n = 0, +/-1, +/-2, +/-3.... The resonances are measured through fragmentation of protonated reserpine. The observed frequencies agree closely with the theoretical values but there are small differences which vary from +0.6% at K = 2 to -2.7% at K = 6. This is believed to be the result of the dependence of the resonant frequencies upon the buffer gas density and/or the excitation amplitude. The resolution of the resonances (measured from the depletion of precursor and formation of fragment ions) increased by a factor of 2 as K increased from 1 to 6. This increase in resolution warrants further investigation into the use of higher order resonances for isolation and excitation of trapped ions.

Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.

How this classification was reachedexpand

Full frame distilled prediction

Teacher imitation

Not calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.

metaresearch head score (Codex)0.000
metaresearch head score (Gemma)0.000
Version: codex-gemma-dda1882f352aValidation status: machine_predicted_unvalidated
Candidate categoriesInsufficient payload (model declined to judge)
Consensus categoriesnone
DomainCandidate signal: none · Consensus signal: none
Study designCandidate signal: Bench or experimental · Consensus signal: Bench or experimental
GenreCandidate signal: Empirical · Consensus signal: Empirical
Teacher disagreement score0.393
Threshold uncertainty score1.000

Codex and Gemma teacher scores by category

CategoryCodexGemma
Metaresearch0.0000.000
Meta-epidemiology (narrow)0.0000.000
Meta-epidemiology (broad)0.0000.001
Bibliometrics0.0000.002
Science and technology studies0.0000.000
Scholarly communication0.0000.000
Open science0.0000.000
Research integrity0.0000.000
Insufficient payload (model declined to judge)0.0010.000

Machine scores (provisional)

The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.

Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.

Opus teacher head0.019
GPT teacher head0.286
Teacher spread0.267 · how far apart the two teachers sit on this one work
Validation statusscore_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from it

Classification

machine, unvalidated

Machine predicted; a candidate call from one teacher head, not a consensus.

Study designBench or experimental
Domainnot available
GenreEmpirical

How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".

Quick stats

Citations39
Published2000
Admission routes1
Has abstractyes

Explore more

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