{"id":"https://openalex.org/W7221830641","doi":"https://doi.org/10.1051/0004-6361/202660656","title":"High-resolution transmission spectroscopy of KELT-18b. Metastable helium detection at 1083 nm","display_name":"High-resolution transmission spectroscopy of KELT-18b. Metastable helium detection at 1083 nm","publication_year":2026,"publication_date":"2026-10-21","ids":{"openalex":"https://openalex.org/W7221830641","doi":"https://doi.org/10.1051/0004-6361/202660656"},"language":"en","primary_location":{"id":"doi:10.1051/0004-6361/202660656","doi":"https://doi.org/10.1051/0004-6361/202660656","is_oa":true,"landing_page_url":"https://doi.org/10.1051/0004-6361/202660656","pdf_url":null,"source":{"id":"https://openalex.org/S205231332","display_name":"Astronomy and Astrophysics","issn_l":"0004-6361","issn":["0004-6361","1432-0746"],"is_oa":true,"is_in_doaj":true,"is_core":true,"listed_in":["anvur-scientific","cwts-core","doaj","dongbi-a","jufo-3","ki-jl-2","norway-2","poland-140","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310319748","host_organization_name":"EDP Sciences","host_organization_lineage":["https://openalex.org/P4310319748","https://openalex.org/P4310319982"],"host_organization_lineage_names":["EDP Sciences","Science Press"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Astronomy &amp; Astrophysics","raw_type":"journal-article"},"volume":null,"type":"article","is_traditional":true,"indexed_in":["arxiv","crossref","datacite","doaj"],"open_access":{"is_oa":true,"oa_status":"gold","oa_url":"https://doi.org/10.1051/0004-6361/202660656","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5158684080","display_name":"M. Chella","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"M. Chella","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"middle","author":{"id":"https://openalex.org/A5158685228","display_name":"M. Monticelli","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"M. Monticelli","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"middle","author":{"id":"https://openalex.org/A5158737713","display_name":"F. Biassoni","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"F. Biassoni","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"middle","author":{"id":"https://openalex.org/A5031995613","display_name":"F. Borsa","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"F. Borsa","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"middle","author":{"id":"https://openalex.org/A5158690808","display_name":"M. Rainer","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"M. Rainer","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"middle","author":{"id":"https://openalex.org/A5158682422","display_name":"G. Guilluy","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"G. Guilluy","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"middle","author":{"id":"https://openalex.org/A5158700844","display_name":"M. Basilicata","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"M. Basilicata","raw_affiliation_strings":[],"raw_orcid":null,"affiliations":[]},{"author_position":"last","author":{"id":"https://openalex.org/A5158710244","display_name":"L. Cabona","orcid":null,"observed_orcids":[]},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"L. Cabona","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":1650,"currency":"EUR","value_usd":1865},"apc_paid":{"value":1650,"currency":"EUR","value_usd":1865},"fwci":0.0,"has_fulltext":true,"cited_by_count":0,"citation_normalized_percentile":{"value":0.68224631,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"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/T10039","display_name":"Stellar, planetary, and galactic studies","score":0.9990000128746033,"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/T10039","display_name":"Stellar, planetary, and galactic studies","score":0.9990000128746033,"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/T12917","display_name":"Astronomy and Astrophysical Research","score":0.0006000000284984708,"subfield":{"id":"https://openalex.org/subfields/3105","display_name":"Instrumentation"},"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/T10325","display_name":"Astro and Planetary Science","score":0.00019999999494757503,"subfield":{"id":"https://openalex.org/subfields/1912","display_name":"Space and Planetary Science"},"field":{"id":"https://openalex.org/fields/19","display_name":"Earth and Planetary Sciences"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/ultra-hot-jupiters","display_name":"ultra-hot Jupiters","score":0.8859999775886536},{"id":"https://openalex.org/keywords/atmospheric-escape","display_name":"atmospheric escape","score":0.7089999914169312},{"id":"https://openalex.org/keywords/photoevaporation","display_name":"photoevaporation","score":0.8769999742507935},{"id":"https://openalex.org/keywords/mass-loss-rate","display_name":"mass loss rate","score":0.9039999842643738},{"id":"https://openalex.org/keywords/evaporation-efficiency","display_name":"evaporation efficiency","score":0.9200000166893005},{"id":"https://openalex.org/keywords/he-h-ratio","display_name":"He/H ratio","score":0.8040000200271606},{"id":"https://openalex.org/keywords/extreme-ultraviolet-irradiation","display_name":"extreme ultraviolet irradiation","score":0.7260000109672546},{"id":"https://openalex.org/keywords/principal-component-analysis","display_name":"principal component analysis","score":0.878000020980835},{"id":"https://openalex.org/keywords/doppler-tomography","display_name":"Doppler tomography","score":0.9269999861717224},{"id":"https://openalex.org/keywords/transmission-spectroscopy","display_name":"transmission spectroscopy","score":0.5590000152587891},{"id":"https://openalex.org/keywords/carmenes","display_name":"CARMENES","score":0.6940000057220459}],"concepts":[{"id":"https://openalex.org/C163479331","wikidata":"https://www.wikidata.org/wiki/Q44559","display_name":"Exoplanet","level":3,"score":0.7052000164985657},{"id":"https://openalex.org/C546029482","wikidata":"https://www.wikidata.org/wiki/Q560","display_name":"Helium","level":2,"score":0.6712999939918518},{"id":"https://openalex.org/C32891209","wikidata":"https://www.wikidata.org/wiki/Q483666","display_name":"Spectroscopy","level":2,"score":0.6417999863624573},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.5151000022888184},{"id":"https://openalex.org/C51244244","wikidata":"https://www.wikidata.org/wiki/Q634","display_name":"Planet","level":2,"score":0.46480000019073486},{"id":"https://openalex.org/C65440619","wikidata":"https://www.wikidata.org/wiki/Q177974","display_name":"Atmosphere (unit)","level":2,"score":0.43459999561309814},{"id":"https://openalex.org/C33390570","wikidata":"https://www.wikidata.org/wiki/Q188463","display_name":"Spectrometer","level":2,"score":0.4318000078201294},{"id":"https://openalex.org/C206489886","wikidata":"https://www.wikidata.org/wiki/Q382979","display_name":"Hot Jupiter","level":4,"score":0.4058000147342682},{"id":"https://openalex.org/C44870925","wikidata":"https://www.wikidata.org/wiki/Q37547","display_name":"Astrophysics","level":1,"score":0.40119999647140503},{"id":"https://openalex.org/C761482","wikidata":"https://www.wikidata.org/wiki/Q118093","display_name":"Transmission (telecommunications)","level":2,"score":0.40070000290870667},{"id":"https://openalex.org/C30475298","wikidata":"https://www.wikidata.org/wiki/Q909554","display_name":"Computational physics","level":1,"score":0.39500001072883606},{"id":"https://openalex.org/C120665830","wikidata":"https://www.wikidata.org/wiki/Q14620","display_name":"Optics","level":1,"score":0.39100000262260437},{"id":"https://openalex.org/C119824511","wikidata":"https://www.wikidata.org/wiki/Q13553575","display_name":"Absorption spectroscopy","level":2,"score":0.3734999895095825},{"id":"https://openalex.org/C2778505590","wikidata":"https://www.wikidata.org/wiki/Q141022","display_name":"Eclipse","level":2,"score":0.36090001463890076},{"id":"https://openalex.org/C146024833","wikidata":"https://www.wikidata.org/wiki/Q1385457","display_name":"Extreme ultraviolet","level":3,"score":0.3546000123023987},{"id":"https://openalex.org/C125287762","wikidata":"https://www.wikidata.org/wiki/Q1758948","display_name":"Absorption (acoustics)","level":2,"score":0.34860000014305115},{"id":"https://openalex.org/C4839761","wikidata":"https://www.wikidata.org/wiki/Q212111","display_name":"Spectral line","level":2,"score":0.34850001335144043},{"id":"https://openalex.org/C192562407","wikidata":"https://www.wikidata.org/wiki/Q228736","display_name":"Materials science","level":0,"score":0.32899999618530273},{"id":"https://openalex.org/C142757262","wikidata":"https://www.wikidata.org/wiki/Q76436","display_name":"Doppler effect","level":2,"score":0.3190000057220459},{"id":"https://openalex.org/C2779843651","wikidata":"https://www.wikidata.org/wiki/Q7390335","display_name":"SIGNAL (programming language)","level":2,"score":0.3025999963283539},{"id":"https://openalex.org/C100905312","wikidata":"https://www.wikidata.org/wiki/Q206717","display_name":"Planetary system","level":3,"score":0.29750001430511475},{"id":"https://openalex.org/C41074950","wikidata":"https://www.wikidata.org/wiki/Q240105","display_name":"Radial velocity","level":3,"score":0.29159998893737793},{"id":"https://openalex.org/C61441594","wikidata":"https://www.wikidata.org/wiki/Q132814","display_name":"Evaporation","level":2,"score":0.29089999198913574},{"id":"https://openalex.org/C89464430","wikidata":"https://www.wikidata.org/wiki/Q849516","display_name":"Metastability","level":2,"score":0.28130000829696655},{"id":"https://openalex.org/C147534773","wikidata":"https://www.wikidata.org/wiki/Q190120","display_name":"Water vapor","level":2,"score":0.2775999903678894},{"id":"https://openalex.org/C184779094","wikidata":"https://www.wikidata.org/wiki/Q26383","display_name":"Atomic physics","level":1,"score":0.2766999900341034},{"id":"https://openalex.org/C96141758","wikidata":"https://www.wikidata.org/wiki/Q216817","display_name":"Emission spectrum","level":3,"score":0.2728999853134155},{"id":"https://openalex.org/C2778022998","wikidata":"https://www.wikidata.org/wiki/Q651136","display_name":"Transit (satellite)","level":3,"score":0.2632000148296356},{"id":"https://openalex.org/C113196181","wikidata":"https://www.wikidata.org/wiki/Q485223","display_name":"Analytical Chemistry (journal)","level":2,"score":0.25060001015663147}],"mesh":[],"locations_count":4,"locations":[{"id":"doi:10.1051/0004-6361/202660656","doi":"https://doi.org/10.1051/0004-6361/202660656","is_oa":true,"landing_page_url":"https://doi.org/10.1051/0004-6361/202660656","pdf_url":null,"source":{"id":"https://openalex.org/S205231332","display_name":"Astronomy and Astrophysics","issn_l":"0004-6361","issn":["0004-6361","1432-0746"],"is_oa":true,"is_in_doaj":true,"is_core":true,"listed_in":["anvur-scientific","cwts-core","doaj","dongbi-a","jufo-3","ki-jl-2","norway-2","poland-140","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310319748","host_organization_name":"EDP Sciences","host_organization_lineage":["https://openalex.org/P4310319748","https://openalex.org/P4310319982"],"host_organization_lineage_names":["EDP Sciences","Science Press"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Astronomy &amp; Astrophysics","raw_type":"journal-article"},{"id":"pmh:oai:arXiv.org:2610.17220","doi":null,"is_oa":true,"landing_page_url":"https://arxiv.org/abs/2610.17220","pdf_url":"https://arxiv.org/pdf/2610.17220","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":"pmh:oai:edpsciences.org:dkey/10.1051/0004-6361/202660656","doi":null,"is_oa":false,"landing_page_url":"https://www.aanda.org/10.1051/0004-6361/202660656/pdf","pdf_url":"https://www.aanda.org/10.1051/0004-6361/202660656/pdf","source":{"id":"https://openalex.org/S4306400744","display_name":"Springer Link (Chiba Institute of Technology)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"listed_in":[],"host_organization":"https://openalex.org/I8488066","host_organization_name":"Chiba Institute of Technology","host_organization_lineage":["https://openalex.org/I8488066"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"https://doi.org/10.1051/0004-6361/202660656","raw_type":"Text"},{"id":"doi:10.48550/arxiv.2610.17220","doi":"https://doi.org/10.48550/arxiv.2610.17220","is_oa":true,"landing_page_url":"https://doi.org/10.48550/arxiv.2610.17220","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":null,"license_id":null,"version":null,"is_accepted":false,"is_published":false,"raw_source_name":null,"raw_type":"Preprint"}],"best_oa_location":{"id":"doi:10.1051/0004-6361/202660656","doi":"https://doi.org/10.1051/0004-6361/202660656","is_oa":true,"landing_page_url":"https://doi.org/10.1051/0004-6361/202660656","pdf_url":null,"source":{"id":"https://openalex.org/S205231332","display_name":"Astronomy and Astrophysics","issn_l":"0004-6361","issn":["0004-6361","1432-0746"],"is_oa":true,"is_in_doaj":true,"is_core":true,"listed_in":["anvur-scientific","cwts-core","doaj","dongbi-a","jufo-3","ki-jl-2","norway-2","poland-140","russia-white-list-1","vabb-shw"],"host_organization":"https://openalex.org/P4310319748","host_organization_name":"EDP Sciences","host_organization_lineage":["https://openalex.org/P4310319748","https://openalex.org/P4310319982"],"host_organization_lineage_names":["EDP Sciences","Science Press"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Astronomy &amp; Astrophysics","raw_type":"journal-article"},"sustainable_development_goals":[],"study_designs":[],"awards":[{"id":"https://openalex.org/G7312380752","display_name":null,"funder_award_id":"PID2023-146210NB-I00","funder_id":"https://openalex.org/F4320335598","funder_display_name":"Agencia Estatal de Investigaci\u00f3n"}],"funders":[{"id":"https://openalex.org/F4320335598","display_name":"Agencia Estatal de Investigaci\u00f3n","ror":"https://ror.org/003x0zc53"}],"has_content":{"pdf":true,"grobid_xml":true},"content_urls":{"pdf":"https://content.openalex.org/works/W7221830641.pdf","grobid_xml":"https://content.openalex.org/works/W7221830641.grobid-xml"},"referenced_works_count":1,"referenced_works":["https://openalex.org/W2857876088"],"related_works":["https://openalex.org/W3131257949","https://openalex.org/W4399618008","https://openalex.org/W3136740483","https://openalex.org/W7127572180","https://openalex.org/W2953463866","https://openalex.org/W4412120288","https://openalex.org/W4384261795","https://openalex.org/W4384306075","https://openalex.org/W7131871827","https://openalex.org/W4387891191"],"abstract_inverted_index":{"Exoplanets":[0],"orbiting":[1,288],"near":[2,319],"their":[3,17],"host":[4,291],"stars":[5],"experience":[6],"intense":[7],"irradiation,":[8],"which":[9],"can":[10],"drive":[11],"the":[12,41,47,62,74,81,87,115,145,153,158,163,170,174,225,239,263,271,284,289,303],"expansion":[13],"and":[14,67,101,141,165,173,182,191,203,217],"escape":[15],"of":[16,46,89,127,209,227,275],"upper":[18],"atmospheres.":[19],"The":[20,132],"near-infrared":[21],"metastable":[22],"helium":[23,175,279],"triplet":[24,124,176],"at":[25,251],"1083.3":[26],"nm":[27],"has":[28],"emerged":[29],"as":[30,104,106,283],"a":[31,57,98,107,122,135,200,252,295],"powerful":[32],"diagnostic":[33],"to":[34,72,144,245,260,305,309],"probe":[35],"these":[36],"mass-loss":[37,201],"processes.":[38],"We":[39],"present":[40],"first":[42],"high-resolution":[43],"transmission":[44,241],"spectroscopy":[45,66],"ultrahot":[48],"Jupiter":[49],"KELT-18b,":[50],"probing":[51],"its":[52],"escaping":[53],"atmosphere":[54,226],"by":[55],"analyzing":[56],"single":[58],"transit":[59],"obtained":[60],"with":[61,139,238,277,293],"CARMENES":[63],"spectrograph.":[64],"Transmission":[65],"Doppler":[68],"tomography":[69],"were":[70,96],"utilized":[71],"isolate":[73],"planetary":[75,192,313],"signal.":[76,160],"To":[77],"mitigate":[78],"contamination":[79],"from":[80],"strong":[82],"telluric":[83],"OH":[84],"lines":[85],"overlapping":[86],"region":[88],"interest,":[90],"two":[91,116],"distinct":[92],"data":[93],"analysis":[94,110],"procedures":[95],"applied:":[97],"standard":[99],"Molecfit":[100],"OH-masking":[102],"approach,":[103],"well":[105],"principal":[108],"component":[109],"(PCA)-based":[111],"method.":[112],"By":[113],"combining":[114],"complementary":[117],"approaches,":[118],"we":[119,168,198,301],"successfully":[120],"detect":[121],"He,I":[123],"absorption":[125],"feature":[126],"1.10":[128],"\u00b1":[129],"0.22%":[130],"(5.1\u03c3).":[131],"signal":[133,314],"exhibits":[134],"velocity":[136],"shift":[137],"consistent":[138],"zero":[140],"is":[142,229,315],"attributed":[143],"exoplanetary":[146],"atmosphere.":[147],"An":[148],"injection":[149,307],"test":[150],"reveals":[151],"that":[152,224],"PCA-based":[154],"method":[155],"significantly":[156],"suppresses":[157],"retrieved":[159],"Additionally,":[161],"using":[162],"ATES":[164],"TPM":[166],"codes,":[167],"modeled":[169],"atmospheric":[171],"photoevaporation":[172],"profile":[177],"for":[178,189,207,256],"different":[179],"He/H":[180,249],"ratios":[181,250],"stellar":[183],"extreme":[184],"ultraviolet":[185],"(XUV)":[186],"fluxes,":[187],"accounting":[188],"instrument":[190],"rotational":[193],"broadening.":[194],"From":[195],"our":[196,233],"simulations":[197,234],"derive":[199],"rate":[202],"an":[204],"evaporation":[205],"efficiency":[206],"KELT-18b":[208,228,282],"10.47":[210],"\u0142eq":[211,215,219,221],"10":[212],"(":[213],")":[214],"11.68":[216],"0.153":[218],"\u03b7":[220],"0.321,":[222],"showing":[223],"undergoing":[230],"photoevaporation.":[231],"Furthermore,":[232,297],"show":[235],"good":[236],"agreement":[237],"observed":[240],"spectrum,":[242],"allowing":[243],"us":[244],"exclude":[246],"very":[247],"low":[248],"3\u03c3":[253],"confidence":[254],"level":[255],"XUV":[257],"fluxes":[258],"up":[259],"approximately":[261],"twice":[262],"nominal":[264],"reconstructed":[265],"value.":[266],"M":[267],"Our":[268],"result":[269],"expands":[270],"known":[272],"parameter":[273],"space":[274],"exoplanets":[276],"confirmed":[278],"absorption,":[280],"establishing":[281],"most":[285],"massive":[286],"planet":[287],"hottest":[290],"star":[292],"such":[294],"detection.":[296],"when":[298],"employing":[299],"PCA,":[300],"emphasize":[302],"need":[304],"perform":[306],"tests":[308],"investigate":[310],"whether":[311],"any":[312],"removed,":[316],"not":[317],"only":[318],"quadrature":[320],"but":[321],"also":[322],"during":[323],"transits.":[324]},"counts_by_year":[],"updated_date":"2026-11-08T12:12:28.789561","created_date":"2026-10-15T00:00:00"}
