{"doi":"10.17615/6hmm-ks37","title":"Theoretical models of spin-exchange optical pumping: Revisited and reconciled","abstract":"Theoretical models for continuous-flow and stopped-flow spin-exchange optical pumping of 129Xe have long predicted much higher 129Xe polarization values than are measured experimentally, leading to a search for additional depolarization mechanisms. In this work, we show that a misapplication of the general theory of spin-exchange optical pumping along with the incorrect use of previously measured spin-exchange constants has been perpetuated in the past 20 years and is the main cause of the long-held discrepancy between theoretical and experimental 129Xe polarization values. Following the standard theory of spin-exchange optical pumping developed almost 40 years ago by Happer et al., we outline the common mistake made in the application of this theory in modern theoretical models and derive a simplified expression of the spin-exchange cross section that can be used to correctly predict 129Xe polarization values under any set of experimental conditions. We show that the complete expression of the spin-exchange cross section derived using the work of Happer et al. predicts spin-exchange rates tenfold higher than those previously assumed in theoretical models of continuous-flow and stopped-flow spin-exchange optical pumping and can fully rectify the long-standing discrepancy between theoretical and experimental polarization values.","journal":"UNC Libraries","year":2022,"id":310624,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9421,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2022-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":971538,"name":"R.T. Branca","orcid":null,"position":1,"is_corresponding":false},{"id":1006667,"name":"M. Kelley","orcid":null,"position":0,"is_corresponding":true}],"reference_count":0,"raw_metadata":null,"created_at":"2026-07-19T00:33:19.712967Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}