J/MNRAS/484/834ivo://CDS.VizieR/J/MNRAS/484/834doi:10.26093/cds/vizier.74840834CDSGiles D.Walkowicz L.2024-08-19T20:17:01Z2022-10-18T12:27:51ZCDS support team

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

cds-question@unistra.frsurveysastrometryvisible-astronomyAdvances in astronomy are often driven by serendipitous discoveries. As survey astronomy continues to grow, the size and complexity of astronomical data bases will increase, and the ability of astronomers to manually scour data and make such discoveries decreases. In this work, we introduce a machine learning-based method to identify anomalies in large data sets to facilitate such discoveries, and apply this method to long cadence light curves from NASA's Kepler Mission. Our method clusters data based on density, identifying anomalies as data that lie outside of dense regions. This work serves as a proof-of-concept case study and we test our method on four quarters of the Kepler long cadence light curves. We use Kepler's most notorious anomaly, Boyajian's star (KIC 8462852), as a rare 'ground truth' for testing outlier identification to verify that objects of genuine scientific interest are included among the identified anomalies. We evaluate the method's ability to identify known anomalies by identifying unusual behaviour in Boyajian's star; we report the full list of identified anomalies for these quarters, and present a sample subset of identified outliers that includes unusual phenomena, objects that are rare in the Kepler field, and data artefacts. By identifying <4 per cent of each quarter as outlying data, we demonstrate that this anomaly detection method can create a more targeted approach in searching for rare and novel phenomena.2019MNRAS.484..834Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/484/834CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/133 : Kepler Input Catalog (Kepler Mission Team, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/484/834https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/484/834http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/484/834https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/484/834https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/484/834http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/484/834GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/484/834/table4 (List of outliers)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/484/834/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/484/834/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/484/834/table4?GETtext/xml+votable180.050000true291.0430583336.593811110.0055555555555555564/922 933-935 944-945 5/3645-3647 3683 3692-3694 3729-3731 3760 3784 3789 3792-3793 6/14559 14567 14573 14575 14577-14579 14730-14731 14738 14744 14746 14749-14751 14780 14782 14792 14794-14795 14816-14818 14826-14827 14830-14831 14914-14915 15044-15045 15057 15059-15062 15140-15142 15144 15146 15152-15153 15155 15161 15176 15178 15200 15202 15232https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/484/834?format=asciiOpticaldefaultJ/MNRAS/484/834/table4List of outliersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC identification numbermeta.id;meta.mainlongRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainTeff? Effective temperatureKphys.temperature.effectiveintnullableE_Teff? Upper error on TeffKstat.error;stat.maxintnullablee_Teff? Lower error on TeffKstat.error;phys.temperature.effectiveintnullablelogg? Surface gravitylog(cm**2.s**-1)phys.gravityfloatnullableE_logg? Upper error on logglog(cm**2.s**-1)stat.error;stat.maxfloatnullablee_logg? Lower error on logglog(cm**2.s**-1)stat.errorfloatnullableKepmag? Kepler magnitudemagphot.mag;em.optfloatnullableQ4Outlier flag on quarter 4 of the Kepler mission (1)meta.codeintQ8Outlier flag on quarter 8 of the Kepler mission (1)meta.codeintQ11Outlier flag on quarter 11 of the Kepler mission (1)meta.codeintQ16Outlier flag on quarter 16 of the Kepler mission (1)meta.codeint