{"id":"https://openalex.org/W7204864459","doi":"https://doi.org/10.48550/arxiv.2608.29682","title":"The multi-frequency radio light curve of the sub-pc SMBH binary candidate PG 1302-102","display_name":"The multi-frequency radio light curve of the sub-pc SMBH binary candidate PG 1302-102","publication_year":2026,"publication_date":"2026-08-30","ids":{"openalex":"https://openalex.org/W7204864459","doi":"https://doi.org/10.48550/arxiv.2608.29682"},"language":"en","primary_location":{"id":"pmh:oai:arXiv.org:2608.29682","doi":null,"is_oa":true,"landing_page_url":"https://arxiv.org/abs/2608.29682","pdf_url":"https://arxiv.org/pdf/2608.29682","source":{"id":"https://openalex.org/S4306400194","display_name":"arXiv (Cornell University)","issn_l":"2331-8422","issn":["2331-8422"],"is_oa":true,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/I205783295","host_organization_name":"Cornell University","host_organization_lineage":["https://openalex.org/I205783295"],"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":"text"},"volume":null,"type":"preprint","is_traditional":true,"indexed_in":["arxiv","datacite"],"open_access":{"is_oa":true,"oa_status":"green","oa_url":"https://arxiv.org/pdf/2608.29682","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5112540761","display_name":"Sayan Basu","orcid":null,"observed_orcids":[]},"institutions":[{"id":"https://openalex.org/I192619145","display_name":"University of the Witwatersrand","ror":"https://ror.org/03rp50x72","country_code":"ZA","type":"education","lineage":["https://openalex.org/I192619145"]}],"countries":["ZA"],"is_corresponding":false,"raw_author_name":"Basu, Sayan","raw_affiliation_strings":["Wits Centre for Astrophysics , School of Physics , University of the Witwatersrand , 1 Jan Smuts Avenue , Johannesburg , 2000 , South Africa"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Wits Centre for Astrophysics , School of Physics , University of the Witwatersrand , 1 Jan Smuts Avenue , Johannesburg , 2000 , South Africa","institution_ids":["https://openalex.org/I192619145"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5041928811","display_name":"Roger P Deane","orcid":"https://orcid.org/0000-0003-1027-5043","observed_orcids":["https://orcid.org/0000-0003-1027-5043"]},"institutions":[{"id":"https://openalex.org/I192619145","display_name":"University of the Witwatersrand","ror":"https://ror.org/03rp50x72","country_code":"ZA","type":"education","lineage":["https://openalex.org/I192619145"]},{"id":"https://openalex.org/I69552723","display_name":"University of Pretoria","ror":"https://ror.org/00g0p6g84","country_code":"ZA","type":"education","lineage":["https://openalex.org/I69552723"]}],"countries":["ZA"],"is_corresponding":false,"raw_author_name":"Deane, Roger P.","raw_affiliation_strings":["Department of Physics , University of Pretoria , Private Bag X20 , Pretoria 0028 , South Africa","Wits Centre for Astrophysics , School of Physics , University of the Witwatersrand , 1 Jan Smuts Avenue , Johannesburg , 2000 , South Africa"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Physics , University of Pretoria , Private Bag X20 , Pretoria 0028 , South Africa","institution_ids":["https://openalex.org/I69552723"]},{"raw_affiliation_string":"Wits Centre for Astrophysics , School of Physics , University of the Witwatersrand , 1 Jan Smuts Avenue , Johannesburg , 2000 , South Africa","institution_ids":["https://openalex.org/I192619145"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5027003606","display_name":"K. W. Bannister","orcid":"https://orcid.org/0000-0003-2149-0363","observed_orcids":["https://orcid.org/0000-0003-2149-0363"]},"institutions":[{"id":"https://openalex.org/I1292875679","display_name":"Commonwealth Scientific and Industrial Research Organisation","ror":"https://ror.org/03qn8fb07","country_code":"AU","type":"government","lineage":["https://openalex.org/I1292875679","https://openalex.org/I2801453606","https://openalex.org/I4387156119"]},{"id":"https://openalex.org/I1299164729","display_name":"Australia Telescope National Facility","ror":"https://ror.org/05qajvd42","country_code":"AU","type":"facility","lineage":["https://openalex.org/I1292875679","https://openalex.org/I1299164729","https://openalex.org/I2801453606","https://openalex.org/I4387156119"]}],"countries":["AU"],"is_corresponding":false,"raw_author_name":"Bannister, Keith W.","raw_affiliation_strings":["ATNF , CSIRO, Space and Astronomy , PO Box 76 , Epping , NSW 1710 Australia"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"ATNF , CSIRO, Space and Astronomy , PO Box 76 , Epping , NSW 1710 Australia","institution_ids":["https://openalex.org/I1292875679","https://openalex.org/I1299164729"]}]}],"institutions":[],"countries_distinct_count":2,"institutions_distinct_count":4,"corresponding_author_ids":[],"corresponding_institution_ids":[],"apc_list":null,"apc_paid":null,"fwci":null,"has_fulltext":true,"cited_by_count":0,"citation_normalized_percentile":null,"cited_by_percentile_year":null,"biblio":{"volume":null,"issue":null,"first_page":null,"last_page":null},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10744","display_name":"Astrophysical Phenomena and Observations","score":0.7914999723434448,"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/T10744","display_name":"Astrophysical Phenomena and Observations","score":0.7914999723434448,"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/T10463","display_name":"Pulsars and Gravitational Waves Research","score":0.13529999554157257,"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/T10026","display_name":"Galaxies: Formation, Evolution, Phenomena","score":0.053700000047683716,"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/supermassive-black-hole-binaries","display_name":"supermassive black hole binaries","score":0.8799999952316284},{"id":"https://openalex.org/keywords/radio-light-curves","display_name":"radio light curves","score":0.734000027179718},{"id":"https://openalex.org/keywords/multi-frequency-radio-emission","display_name":"multi-frequency radio emission","score":0.6010000109672546},{"id":"https://openalex.org/keywords/nanohertz-gravitational-wave-background","display_name":"nanohertz gravitational-wave background","score":0.7720000147819519},{"id":"https://openalex.org/keywords/gravitational-wave-emission","display_name":"gravitational wave emission","score":0.5440000295639038},{"id":"https://openalex.org/keywords/quasar-variability","display_name":"quasar variability","score":0.44999998807907104}],"concepts":[{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.894599974155426},{"id":"https://openalex.org/C130726490","wikidata":"https://www.wikidata.org/wiki/Q675076","display_name":"Light curve","level":2,"score":0.8891000151634216},{"id":"https://openalex.org/C135041427","wikidata":"https://www.wikidata.org/wiki/Q83373","display_name":"Quasar","level":3,"score":0.7788000106811523},{"id":"https://openalex.org/C44870925","wikidata":"https://www.wikidata.org/wiki/Q37547","display_name":"Astrophysics","level":1,"score":0.7190999984741211},{"id":"https://openalex.org/C173120059","wikidata":"https://www.wikidata.org/wiki/Q40392","display_name":"Supermassive black hole","level":3,"score":0.600600004196167},{"id":"https://openalex.org/C42061751","wikidata":"https://www.wikidata.org/wiki/Q2280060","display_name":"Spectral index","level":3,"score":0.5752999782562256},{"id":"https://openalex.org/C190330329","wikidata":"https://www.wikidata.org/wiki/Q190035","display_name":"Gravitational wave","level":2,"score":0.5702999830245972},{"id":"https://openalex.org/C48372109","wikidata":"https://www.wikidata.org/wiki/Q3913","display_name":"Binary number","level":2,"score":0.5328999757766724},{"id":"https://openalex.org/C197129107","wikidata":"https://www.wikidata.org/wiki/Q1921621","display_name":"Merge (version control)","level":2,"score":0.43709999322891235},{"id":"https://openalex.org/C33024259","wikidata":"https://www.wikidata.org/wiki/Q76250","display_name":"Redshift","level":3,"score":0.43479999899864197},{"id":"https://openalex.org/C1276947","wikidata":"https://www.wikidata.org/wiki/Q333","display_name":"Astronomy","level":1,"score":0.41190001368522644},{"id":"https://openalex.org/C202572682","wikidata":"https://www.wikidata.org/wiki/Q35273","display_name":"Optical telescope","level":3,"score":0.374099999666214},{"id":"https://openalex.org/C4839761","wikidata":"https://www.wikidata.org/wiki/Q212111","display_name":"Spectral line","level":2,"score":0.36489999294281006},{"id":"https://openalex.org/C2780848835","wikidata":"https://www.wikidata.org/wiki/Q4213","display_name":"Telescope","level":2,"score":0.33410000801086426},{"id":"https://openalex.org/C32602459","wikidata":"https://www.wikidata.org/wiki/Q4913879","display_name":"Binary black hole","level":3,"score":0.32420000433921814},{"id":"https://openalex.org/C2985930086","wikidata":"https://www.wikidata.org/wiki/Q65037198","display_name":"Light emission","level":2,"score":0.3163999915122986},{"id":"https://openalex.org/C68271606","wikidata":"https://www.wikidata.org/wiki/Q625648","display_name":"Photometry (optics)","level":3,"score":0.29490000009536743},{"id":"https://openalex.org/C96141758","wikidata":"https://www.wikidata.org/wiki/Q216817","display_name":"Emission spectrum","level":3,"score":0.2944999933242798},{"id":"https://openalex.org/C120665830","wikidata":"https://www.wikidata.org/wiki/Q14620","display_name":"Optics","level":1,"score":0.2906999886035919},{"id":"https://openalex.org/C50341732","wikidata":"https://www.wikidata.org/wiki/Q880302","display_name":"Black hole (networking)","level":5,"score":0.28439998626708984},{"id":"https://openalex.org/C32224563","wikidata":"https://www.wikidata.org/wiki/Q37640","display_name":"Orbital period","level":3,"score":0.2793999910354614},{"id":"https://openalex.org/C193786831","wikidata":"https://www.wikidata.org/wiki/Q50053","display_name":"Binary star","level":3,"score":0.2793999910354614},{"id":"https://openalex.org/C51493423","wikidata":"https://www.wikidata.org/wiki/Q2486351","display_name":"Superluminal motion","level":2,"score":0.2770000100135803},{"id":"https://openalex.org/C26405456","wikidata":"https://www.wikidata.org/wiki/Q338","display_name":"Cosmology","level":2,"score":0.2572999894618988}],"mesh":[],"locations_count":2,"locations":[{"id":"pmh:oai:arXiv.org:2608.29682","doi":null,"is_oa":true,"landing_page_url":"https://arxiv.org/abs/2608.29682","pdf_url":"https://arxiv.org/pdf/2608.29682","source":{"id":"https://openalex.org/S4306400194","display_name":"arXiv (Cornell University)","issn_l":"2331-8422","issn":["2331-8422"],"is_oa":true,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/I205783295","host_organization_name":"Cornell University","host_organization_lineage":["https://openalex.org/I205783295"],"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":"text"},{"id":"doi:10.48550/arxiv.2608.29682","doi":"https://doi.org/10.48550/arxiv.2608.29682","is_oa":true,"landing_page_url":"https://doi.org/10.48550/arxiv.2608.29682","pdf_url":null,"source":{"id":"https://openalex.org/S4306400194","display_name":"arXiv (Cornell University)","issn_l":"2331-8422","issn":["2331-8422"],"is_oa":true,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/I205783295","host_organization_name":"Cornell University","host_organization_lineage":["https://openalex.org/I205783295"],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":null,"is_accepted":false,"is_published":false,"raw_source_name":null,"raw_type":"Preprint"}],"best_oa_location":{"id":"pmh:oai:arXiv.org:2608.29682","doi":null,"is_oa":true,"landing_page_url":"https://arxiv.org/abs/2608.29682","pdf_url":"https://arxiv.org/pdf/2608.29682","source":{"id":"https://openalex.org/S4306400194","display_name":"arXiv (Cornell University)","issn_l":"2331-8422","issn":["2331-8422"],"is_oa":true,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/I205783295","host_organization_name":"Cornell University","host_organization_lineage":["https://openalex.org/I205783295"],"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":"text"},"sustainable_development_goals":[],"study_designs":[],"awards":[],"funders":[{"id":"https://openalex.org/F4320320671","display_name":"National Research Foundation","ror":"https://ror.org/05s0g1g46"},{"id":"https://openalex.org/F4320320692","display_name":"University of Pretoria","ror":"https://ror.org/00g0p6g84"},{"id":"https://openalex.org/F4320321970","display_name":"University of the Western Cape","ror":"https://ror.org/00h2vm590"},{"id":"https://openalex.org/F4320322663","display_name":"Universiteit Stellenbosch","ror":"https://ror.org/05bk57929"},{"id":"https://openalex.org/F4320322696","display_name":"Cape Peninsula University of Technology","ror":"https://ror.org/056e9h402"},{"id":"https://openalex.org/F4320324164","display_name":"University of Cape Town","ror":"https://ror.org/03p74gp79"}],"has_content":{"pdf":true,"grobid_xml":true},"content_urls":{"pdf":"https://content.openalex.org/works/W7204864459.pdf","grobid_xml":"https://content.openalex.org/works/W7204864459.grobid-xml"},"referenced_works_count":2,"referenced_works":["https://openalex.org/W2994720460","https://openalex.org/W4387994934"],"related_works":["https://openalex.org/W2011739082","https://openalex.org/W2909524582","https://openalex.org/W3133395520","https://openalex.org/W1509673159","https://openalex.org/W2118811399","https://openalex.org/W3086628218","https://openalex.org/W2790263983","https://openalex.org/W1468711679","https://openalex.org/W7119511607","https://openalex.org/W2047465039"],"abstract_inverted_index":{"Supermassive":[0],"black":[1,119],"hole":[2],"binary":[3,102],"(SMBHB)":[4],"candidates":[5,45],"with":[6,107,150,202,206],"sub-parsec":[7],"(sub-pc)":[8],"orbital":[9],"separations":[10],"are":[11,124],"rare,":[12],"high-value":[13],"systems,":[14],"thought":[15],"to":[16,126,133],"be":[17,239],"the":[18,22,67,90,115,158,180,195,207,211,222,254,258,270],"dominant":[19],"sources":[20,38],"of":[21,44,52,66,73,82,92,104,144,179,192,269],"recently":[23,212],"detected":[24],"nanoHertz":[25],"(nHz)":[26],"gravitational":[27],"wave":[28],"(GW)":[29],"background.":[30],"Alongside":[31],"pulsar-timing-array":[32],"searches":[33],"for":[34],"localized":[35],"nHz":[36],"GW":[37,134],"from":[39,49,157],"SMBHBs,":[40],"an":[41,264],"increasing":[42],"number":[43],"have":[46],"been":[47],"identified":[48],"synoptic":[50],"surveys":[51],"large":[53],"quasar":[54,68],"optical":[55,63,184,208,216,236,259],"light":[56,64,141,167,227],"curves":[57],"over":[58,85],"increasingly":[59],"long":[60],"baselines.":[61],"The":[62,164],"curve":[65,142,168],"PG~1302-102":[69,145],"at":[70,172,183,200],"a":[71,76,97,101,108,138,147,203],"redshift":[72],"$z=0.278$":[74],"exhibits":[75],"pronounced,":[77],"smoothly":[78],"varying":[79],"periodic":[80],"signal":[81],"~5.2":[83],"years":[84],"approximately":[86],"20":[87],"years.":[88],"Although":[89],"cause":[91],"this":[93,112,250],"periodicity":[94,181,193,217,237,260],"remains":[95],"debated,":[96],"plausible":[98],"explanation":[99],"is":[100,169,218],"system":[103],"two":[105,230],"SMBHs":[106],"sub-pc":[109],"separation.":[110],"At":[111],"close":[113],"distance,":[114],"$10^{8.3-9.4}":[116],"M_{\\odot}$":[117],"nuclear":[118],"holes":[120],"in":[121,194,215,221],"PG":[122],"1302-102":[123],"expected":[125],"merge":[127],"within":[128],"$\\sim$$10^{5}$":[129],"yr":[130],"solely":[131],"due":[132],"emission.":[135],"We":[136,247],"present":[137,220],"multi-frequency":[139],"radio":[140,166,223,234],"analysis":[143],"spanning":[146],"$\\sim$19-year":[148],"baseline,":[149],"observations":[151],"between":[152],"2005":[153],"and":[154,235,262],"2024":[155],"drawn":[156],"Australian":[159],"Telescope":[160],"Compact":[161],"Array":[162],"(ATCA).":[163],"ATCA":[165],"highly":[170],"variable":[171],"5.5~GHz":[173],"but":[174],"shows":[175],"no":[176],"significant":[177],"evidence":[178,191],"seen":[182],"wavelengths.":[185],"However,":[186],"we":[187],"report":[188],"fractionally":[189],"stronger":[190],"in-band":[196,224],"spectral":[197,225],"index":[198,226],"time-series":[199],"5.5~GHz,":[201],"period":[204],"consistent":[205],"periodicity.":[209],"Furthermore,":[210],"reported":[213],"change":[214],"also":[219],"curve.":[228],"These":[229],"results":[231],"suggest":[232],"that":[233,249],"may":[238],"physically":[240],"coupled":[241],"despite":[242,257],"very":[243],"different":[244],"emission":[245],"mechanisms.":[246],"argue":[248],"radio-optical":[251],"coupling":[252],"reinforces":[253],"SMBHB":[255],"interpretation,":[256],"change,":[261],"provides":[263],"intriguing":[265],"case":[266],"study":[267],"ahead":[268],"LSST-SKAO":[271],"era.":[272]},"counts_by_year":[],"updated_date":"2026-11-07T11:25:07.637180","created_date":"2026-09-02T00:00:00"}