J/other/NatAs/2.ivo://CDS.VizieR/J/other/NatAs/2.778doi:10.26093/cds/vizier/dt/ckhhiCDSKaminski T.Tylenda R.Menten K.M.Karakas A.Winters J.M.,Breier A.A.Wong K.T.Giesen T.F.Patel N.A.2026-03-04T20:02:59Z2018-11-06T14:09:18ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frradio-spectroscopyspectroscopyDecades ago, {gamma}-ray observatories identified diffuse Galactic emission at 1.809MeV originating from {beta}^+^ decays of an isotope of aluminium, ^26^Al, that has a mean lifetime of 1.04 million years. Objects responsible for the production of this radioactive isotope have never been directly identified owing to insufficient angular resolutions and sensitivities of the {gamma}-ray observatories. Here, we report observations of millimetre-wave rotational lines of the isotopologue of aluminium monofluoride that contains the radioactive isotope (^26^AlF). The emission is observed towards CK Vul, which is thought to be a remnant of a stellar merger. Our constraints on the production of ^26^Al, combined with the estimates on the merger rate, make it unlikely that objects similar to CK Vul are major producers of Galactic ^26^Al. However, the observation may be a stepping stone for unambiguous identification of other Galactic sources of ^26^Al. Moreover, a high content of ^26^Al in the remnant indicates that, before the merger, the CK Vul system contained at least one solar-mass star that evolved to the red giant branch.2018NatAs...2..778Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/other/NatAs/2.778CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/other/NatAs/2.778https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/other/NatAs/2.778http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/other/NatAs/2.778https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/other/NatAs/2.778https://vizier.iucaa.in/viz-bin/votable?-source=J/other/NatAs/2.778http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/other/NatAs/2.778GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapMillimeterdefaultJ/other/NatAs/2.778/linelist*List of hyperfine rotational transitions of ^26^Al^19^F up to 1.8THzrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMoleculeMolecule designation (Molecule)meta.id;meta.maincharM1Mainfold of upper state (Mprime)phys.atmol.qncharJ1Total angular momentum of upper state (Jprime)phys.angMomentumintS1Symmetry of upper state (Sprime)phys.atmol.configurationintN1Eigenvalue number for upper state (#prime)phys.atmolintM2Mainfold of lower state (Mbis)phys.atmol.qncharJ2Total angular momentum of lower state (Jbis)phys.angMomentumintS2Symmetry of lower state (Sbis)phys.atmol.configurationintN2Eigenvalue number for lower state (#bis)phys.atmolintPositionFrequency of the component in MHz (Position)MHzem.freqdoubleStdDevOne standard deviation uncertainty in frequency (StdDev)MHzstat.error;em.freqfloatStrengthSpectroscopic strength of the component (Strength)phys.atmol.collStrengthdoubleWidth[0] Component width (all set to zero) (Width)spect.line.widthdoubledeltaJTransition quantum numbers (deltaJ) (1)phys.atmol.qn;phys.atmol.transitionchar