{"id":"https://openalex.org/W2048755753","doi":"https://doi.org/10.1086/153093","title":"An atlas of Seyfert galaxies","display_name":"An atlas of Seyfert galaxies","publication_year":1974,"publication_date":"1974-09-01","ids":{"openalex":"https://openalex.org/W2048755753","doi":"https://doi.org/10.1086/153093","mag":"2048755753"},"language":"en","primary_location":{"id":"doi:10.1086/153093","doi":"https://doi.org/10.1086/153093","is_oa":false,"landing_page_url":"https://doi.org/10.1086/153093","pdf_url":null,"source":{"id":"https://openalex.org/S1980519","display_name":"The Astrophysical Journal","issn_l":"0004-637X","issn":["0004-637X","1538-4357"],"is_oa":false,"is_in_doaj":true,"is_core":true,"listed_in":["anvur-scientific","cwts-core","doaj","dongbi-a","jufo-1","ki-jl-1","norway-2","oarl","poland-140","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310320083","host_organization_name":"IOP Publishing","host_organization_lineage":["https://openalex.org/P4310320083","https://openalex.org/P4310311669"],"host_organization_lineage_names":["IOP Publishing","Institute of Physics"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"The Astrophysical Journal","raw_type":"journal-article"},"volume":null,"type":"article","is_traditional":true,"indexed_in":["crossref","doaj"],"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/A5109449303","display_name":"Edward Ye. Khachikian","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"E. Y. Khachikian","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"last","author":{"id":"https://openalex.org/A5009038521","display_name":"D. W. Weedman","orcid":"https://orcid.org/0000-0003-1775-512X","observed_orcids":["https://orcid.org/0000-0003-1775-512X"]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"D. W. Weedman","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]}],"institutions":[],"countries_distinct_count":0,"institutions_distinct_count":0,"corresponding_author_ids":[],"corresponding_institution_ids":[],"apc_list":{"value":4499,"currency":"USD","value_usd":4499},"apc_paid":null,"fwci":6.8214,"has_fulltext":false,"cited_by_count":335,"citation_normalized_percentile":{"value":0.96311208,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":97,"max":100},"biblio":{"volume":"192","issue":null,"first_page":"581","last_page":"581"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10026","display_name":"Galaxies: Formation, Evolution, Phenomena","score":0.9980000257492065,"subfield":{"id":"https://openalex.org/subfields/3103","display_name":"Astronomy and Astrophysics"},"field":{"id":"https://openalex.org/fields/31","display_name":"Physics and Astronomy"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T10026","display_name":"Galaxies: Formation, Evolution, Phenomena","score":0.9980000257492065,"subfield":{"id":"https://openalex.org/subfields/3103","display_name":"Astronomy and Astrophysics"},"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/T10744","display_name":"Astrophysical Phenomena and Observations","score":0.000699999975040555,"subfield":{"id":"https://openalex.org/subfields/3103","display_name":"Astronomy and Astrophysics"},"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/T10039","display_name":"Stellar, planetary, and galactic studies","score":0.00039999998989515007,"subfield":{"id":"https://openalex.org/subfields/3103","display_name":"Astronomy and Astrophysics"},"field":{"id":"https://openalex.org/fields/31","display_name":"Physics and Astronomy"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/seyfert-galaxies","display_name":"Seyfert galaxies","score":1.0},{"id":"https://openalex.org/keywords/active-galactic-nuclei","display_name":"active galactic nuclei","score":0.921999990940094},{"id":"https://openalex.org/keywords/cosmological-redshift","display_name":"cosmological redshift","score":0.8799999952316284},{"id":"https://openalex.org/keywords/ubv-photometry","display_name":"UBV photometry","score":0.7310000061988831},{"id":"https://openalex.org/keywords/optical-spectra","display_name":"optical spectra","score":0.5879999995231628},{"id":"https://openalex.org/keywords/quasars","display_name":"quasars","score":0.8339999914169312}],"concepts":[{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.9363342523574829},{"id":"https://openalex.org/C44870925","wikidata":"https://www.wikidata.org/wiki/Q37547","display_name":"Astrophysics","level":1,"score":0.7810611724853516},{"id":"https://openalex.org/C98444146","wikidata":"https://www.wikidata.org/wiki/Q318","display_name":"Galaxy","level":2,"score":0.7666720151901245},{"id":"https://openalex.org/C2776968204","wikidata":"https://www.wikidata.org/wiki/Q3412366","display_name":"QSOS","level":4,"score":0.7003931403160095},{"id":"https://openalex.org/C33024259","wikidata":"https://www.wikidata.org/wiki/Q76250","display_name":"Redshift","level":3,"score":0.6472250819206238},{"id":"https://openalex.org/C135041427","wikidata":"https://www.wikidata.org/wiki/Q83373","display_name":"Quasar","level":3,"score":0.6051443219184875},{"id":"https://openalex.org/C1276947","wikidata":"https://www.wikidata.org/wiki/Q333","display_name":"Astronomy","level":1,"score":0.5545580983161926},{"id":"https://openalex.org/C89108925","wikidata":"https://www.wikidata.org/wiki/Q1565388","display_name":"Luminous infrared galaxy","level":3,"score":0.5442526340484619},{"id":"https://openalex.org/C26405456","wikidata":"https://www.wikidata.org/wiki/Q338","display_name":"Cosmology","level":2,"score":0.4927697479724884},{"id":"https://openalex.org/C43481613","wikidata":"https://www.wikidata.org/wiki/Q46587","display_name":"Active galactic nucleus","level":3,"score":0.4846099317073822}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1086/153093","doi":"https://doi.org/10.1086/153093","is_oa":false,"landing_page_url":"https://doi.org/10.1086/153093","pdf_url":null,"source":{"id":"https://openalex.org/S1980519","display_name":"The Astrophysical Journal","issn_l":"0004-637X","issn":["0004-637X","1538-4357"],"is_oa":false,"is_in_doaj":true,"is_core":true,"listed_in":["anvur-scientific","cwts-core","doaj","dongbi-a","jufo-1","ki-jl-1","norway-2","oarl","poland-140","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310320083","host_organization_name":"IOP Publishing","host_organization_lineage":["https://openalex.org/P4310320083","https://openalex.org/P4310311669"],"host_organization_lineage_names":["IOP Publishing","Institute of Physics"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"The Astrophysical Journal","raw_type":"journal-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":0,"referenced_works":[],"related_works":["https://openalex.org/W3019888217","https://openalex.org/W1618140166","https://openalex.org/W3105037118","https://openalex.org/W3105156008","https://openalex.org/W3091223498","https://openalex.org/W2039311986","https://openalex.org/W3174720068","https://openalex.org/W3042497634","https://openalex.org/W75030913","https://openalex.org/W7036203057"],"abstract_inverted_index":{"Data":[0],"now":[1],"available":[2],"for":[3,32,43,62],"71":[4],"Seyfert":[5,64],"galaxies":[6],"are":[7,30,56],"summarized":[8],"and":[9,26],"discussed.":[10],"A":[11,35],"collection":[12],"of":[13,23,47],"37":[14],"spectra":[15],"is":[16,39,51,71],"presented":[17],"to":[18,41,73],"illustrate":[19],"the":[20,44,54,69],"spectral":[21],"characteristics":[22],"these":[24],"galaxies,":[25,48],"new":[27],"UBV":[28],"data":[29],"included":[31],"18":[33],"galaxies.":[34],"well-defined":[36],"angular-diameter-redshift":[37],"relation":[38],"found":[40],"exist":[42],"total":[45],"sample":[46],"so":[49],"it":[50],"concluded":[52],"that":[53],"redshifts":[55],"cosmological.":[57],"The":[58],"mean":[59],"ultraviolet":[60,80],"magnitude":[61],"40":[63],"nuclei":[65,78],"whose":[66],"properties":[67],"resemble":[68],"QSOs":[70],"calculated":[72],"be":[74],"-20.4,":[75],"with":[76],"21":[77],"having":[79],"magnitudes":[81],"greater":[82],"than":[83,87],"-20":[84],"but":[85],"less":[86],"-21.5.":[88]},"counts_by_year":[{"year":2026,"cited_by_count":16},{"year":2025,"cited_by_count":13},{"year":2024,"cited_by_count":14},{"year":2023,"cited_by_count":11},{"year":2022,"cited_by_count":6},{"year":2021,"cited_by_count":14},{"year":2020,"cited_by_count":6},{"year":2019,"cited_by_count":9},{"year":2018,"cited_by_count":13},{"year":2017,"cited_by_count":8},{"year":2016,"cited_by_count":13},{"year":2015,"cited_by_count":8},{"year":2014,"cited_by_count":5},{"year":2013,"cited_by_count":11},{"year":2012,"cited_by_count":9}],"updated_date":"2026-11-07T11:25:07.637180","created_date":"2016-06-24T00:00:00"}