{"id":"https://openalex.org/W2147647564","doi":"https://doi.org/10.1364/josa.52.000507","title":"Primary Standard of Length","display_name":"Primary Standard of Length","publication_year":1962,"publication_date":"1962-05-01","ids":{"openalex":"https://openalex.org/W2147647564","doi":"https://doi.org/10.1364/josa.52.000507","mag":"2147647564"},"language":"en","primary_location":{"id":"doi:10.1364/josa.52.000507","doi":"https://doi.org/10.1364/josa.52.000507","is_oa":false,"landing_page_url":"https://doi.org/10.1364/josa.52.000507","pdf_url":null,"source":{"id":"https://openalex.org/S4210189509","display_name":"Journal of the Optical Society of America","issn_l":"0030-3941","issn":["0030-3941","2375-1037"],"is_oa":false,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/P4310315679","host_organization_name":"Optica Publishing Group","host_organization_lineage":["https://openalex.org/P4310315679"],"host_organization_lineage_names":["Optica Publishing Group"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Journal of the Optical Society of America","raw_type":"journal-article"},"volume":null,"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5072238932","display_name":"Kenneth M. Baird","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I4210159778","display_name":"National Research Council Canada","ror":"https://ror.org/04mte1k06","country_code":"CA","type":"government","lineage":["https://openalex.org/I4210159778"]}],"countries":["CA"],"is_corresponding":false,"raw_author_name":"K. M. Baird","raw_affiliation_strings":["Division of Applied Physics, National Research Council, Ottawa, Canada"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Division of Applied Physics, National Research Council, Ottawa, Canada","institution_ids":["https://openalex.org/I4210159778"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5070863505","display_name":"D. S. Smith","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I4210159778","display_name":"National Research Council Canada","ror":"https://ror.org/04mte1k06","country_code":"CA","type":"government","lineage":["https://openalex.org/I4210159778"]}],"countries":["CA"],"is_corresponding":false,"raw_author_name":"D. S. Smith","raw_affiliation_strings":["Division of Applied Physics, National Research Council, Ottawa, Canada"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Division of Applied Physics, National Research Council, Ottawa, Canada","institution_ids":["https://openalex.org/I4210159778"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":1,"corresponding_author_ids":[],"corresponding_institution_ids":["https://openalex.org/I4210159778"],"apc_list":null,"apc_paid":null,"fwci":13.1057,"has_fulltext":false,"cited_by_count":15,"citation_normalized_percentile":{"value":0.98820755,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":null,"biblio":{"volume":"52","issue":"5","first_page":"507","last_page":"507"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T11890","display_name":"Scientific Measurement and Uncertainty Evaluation","score":0.9911999702453613,"subfield":{"id":"https://openalex.org/subfields/1804","display_name":"Statistics, Probability and Uncertainty"},"field":{"id":"https://openalex.org/fields/18","display_name":"Decision Sciences"},"domain":{"id":"https://openalex.org/domains/2","display_name":"Social Sciences"}},"topics":[{"id":"https://openalex.org/T11890","display_name":"Scientific Measurement and Uncertainty Evaluation","score":0.9911999702453613,"subfield":{"id":"https://openalex.org/subfields/1804","display_name":"Statistics, Probability and Uncertainty"},"field":{"id":"https://openalex.org/fields/18","display_name":"Decision Sciences"},"domain":{"id":"https://openalex.org/domains/2","display_name":"Social Sciences"}},{"id":"https://openalex.org/T12004","display_name":"Advanced Frequency and Time Standards","score":0.006500000134110451,"subfield":{"id":"https://openalex.org/subfields/3107","display_name":"Atomic and Molecular Physics, and Optics"},"field":{"id":"https://openalex.org/fields/31","display_name":"Physics and Astronomy"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T12019","display_name":"Calibration and Measurement Techniques","score":0.000699999975040555,"subfield":{"id":"https://openalex.org/subfields/2202","display_name":"Aerospace Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/atomic-clocks","display_name":"atomic clocks","score":0.36899998784065247},{"id":"https://openalex.org/keywords/length-metrology","display_name":"length metrology","score":0.531000018119812},{"id":"https://openalex.org/keywords/frequency-measurement-accuracy","display_name":"frequency measurement accuracy","score":0.30399999022483826}],"concepts":[{"id":"https://openalex.org/C120665830","wikidata":"https://www.wikidata.org/wiki/Q14620","display_name":"Optics","level":1,"score":0.44443079829216003},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.19278454780578613}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.1364/josa.52.000507","doi":"https://doi.org/10.1364/josa.52.000507","is_oa":false,"landing_page_url":"https://doi.org/10.1364/josa.52.000507","pdf_url":null,"source":{"id":"https://openalex.org/S4210189509","display_name":"Journal of the Optical Society of America","issn_l":"0030-3941","issn":["0030-3941","2375-1037"],"is_oa":false,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/P4310315679","host_organization_name":"Optica Publishing Group","host_organization_lineage":["https://openalex.org/P4310315679"],"host_organization_lineage_names":["Optica Publishing Group"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Journal of the Optical Society of America","raw_type":"journal-article"},{"id":"pmh:oai:cisti-icist.nrc-cnrc.ca:cistinparc:8900294","doi":null,"is_oa":false,"landing_page_url":"https://nrc-publications.canada.ca/eng/view/object/?id=3e79e8f7-71c9-4480-a72a-41a3520b1301","pdf_url":null,"source":{"id":"https://openalex.org/S7407055245","display_name":"NPARC","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":null,"host_organization_name":null,"host_organization_lineage":[],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":null,"raw_type":"article"}],"best_oa_location":null,"sustainable_development_goals":[],"study_designs":[],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":9,"referenced_works":["https://openalex.org/W1980297943","https://openalex.org/W1980602297","https://openalex.org/W2025035374","https://openalex.org/W2030501604","https://openalex.org/W2053594403","https://openalex.org/W2079207127","https://openalex.org/W2113790188","https://openalex.org/W2161586869","https://openalex.org/W2514270783"],"related_works":["https://openalex.org/W2166348417","https://openalex.org/W1988640409","https://openalex.org/W135010500","https://openalex.org/W2285432213","https://openalex.org/W2036420756","https://openalex.org/W1999592974","https://openalex.org/W4250308312","https://openalex.org/W4220829749","https://openalex.org/W2020900445","https://openalex.org/W81618908"],"abstract_inverted_index":{"The":[0,35],"primary":[1],"standard":[2,53],"of":[3,9,14,21,28,42,46,57,71],"length":[4],"is":[5],"defined":[6,52],"in":[7],"terms":[8],"the":[10,22,26,39,43,51],"unperturbed":[11],"2p10\u22125d5":[12],"radiation":[13],"Kr-86.":[15],"This":[16],"paper":[17],"reports":[18],"new":[19],"measurements":[20],"perturbations":[23],"due":[24],"to":[25,54],"conditions":[27],"excitation":[29],"necessary":[30],"for":[31],"its":[32],"practical":[33],"realization.":[34],"results":[36],"confirm":[37],"that":[38],"present":[40],"recommendation":[41],"International":[44],"Committee":[45],"Weights":[47],"and":[48,61],"Measures":[49],"yields":[50],"an":[55,65,69],"accuracy":[56],"better":[58],"than":[59],"1:108":[60],"they":[62],"indicate":[63],"how":[64],"improvement":[66],"by":[67,76],"about":[68],"order":[70],"magnitude":[72],"may":[73],"be":[74],"realized":[75],"more":[77],"exact":[78],"specifications.":[79]},"counts_by_year":[],"updated_date":"2026-09-22T06:50:58.402377","created_date":"2016-06-24T00:00:00"}
