Matches in SemOpenAlex for { <https://semopenalex.org/work/W2893263816> ?p ?o ?g. }
- W2893263816 abstract "Active galactic nuclei (AGN) that show strong rest-frame optical/UV variability in their blue continuum and broad line emission are classified as changing-look AGN, or at higher luminosities changing look quasars (CLQs). These surprisingly large and sometimes rapid transitions challenge accepted models of quasar physics and duty cycles, offer several new avenues for study of quasar host galaxies, and open a wider interpretation of the cause of differences between broad and narrow line AGN. To better characterize extreme quasar variability, we present follow-up spectroscopy as part of a comprehensive search for CLQs across the full SDSS footprint using spectroscopically confirmed quasars from the SDSS DR7 catalog. Our primary selection requires large-amplitude (|Delta g|>1 mag, |Delta r|>0.5 mag) variability over any of the available time baselines probed by the SDSS and Pan-STARRS 1 surveys. We employ photometry from the Catalina Sky Survey to verify variability behavior in CLQ candidates where available, and confirm CLQs using optical spectroscopy from the William Herschel, MMT, Magellan, and Palomar telescopes. For our adopted S/N threshold on variability of broad Hbeta emission, we find 17 new CLQs, yielding a confirmation rate of >~ 20%. These candidates are at lower Eddington ratio relative to the overall quasar population which supports a disk-wind model for the broad line region. Based on our sample, the CLQ fraction increases from 10% to roughly half as the continuum flux ratio between repeat spectra at 3420 Angstroms increases from 1.5 to 6. We release a catalog of over 200 highly variable candidates to facilitate future CLQ searches." @default.
- W2893263816 created "2018-10-05" @default.
- W2893263816 creator A5002637900 @default.
- W2893263816 creator A5008481255 @default.
- W2893263816 creator A5012492950 @default.
- W2893263816 creator A5021929791 @default.
- W2893263816 creator A5026454021 @default.
- W2893263816 creator A5032947191 @default.
- W2893263816 creator A5036888763 @default.
- W2893263816 creator A5039703984 @default.
- W2893263816 creator A5040331573 @default.
- W2893263816 creator A5047654208 @default.
- W2893263816 creator A5054115522 @default.
- W2893263816 creator A5060836964 @default.
- W2893263816 creator A5066592371 @default.
- W2893263816 creator A5070619859 @default.
- W2893263816 creator A5073008745 @default.
- W2893263816 creator A5084696446 @default.
- W2893263816 creator A5088650111 @default.
- W2893263816 creator A5090077382 @default.
- W2893263816 date "2018-09-28" @default.
- W2893263816 modified "2023-09-27" @default.
- W2893263816 title "Changing-Look Quasar Candidates: First Results from Follow-up Spectroscopy" @default.
- W2893263816 hasPublicationYear "2018" @default.
- W2893263816 type Work @default.
- W2893263816 sameAs 2893263816 @default.
- W2893263816 citedByCount "0" @default.
- W2893263816 crossrefType "posted-content" @default.
- W2893263816 hasAuthorship W2893263816A5002637900 @default.
- W2893263816 hasAuthorship W2893263816A5008481255 @default.
- W2893263816 hasAuthorship W2893263816A5012492950 @default.
- W2893263816 hasAuthorship W2893263816A5021929791 @default.
- W2893263816 hasAuthorship W2893263816A5026454021 @default.
- W2893263816 hasAuthorship W2893263816A5032947191 @default.
- W2893263816 hasAuthorship W2893263816A5036888763 @default.
- W2893263816 hasAuthorship W2893263816A5039703984 @default.
- W2893263816 hasAuthorship W2893263816A5040331573 @default.
- W2893263816 hasAuthorship W2893263816A5047654208 @default.
- W2893263816 hasAuthorship W2893263816A5054115522 @default.
- W2893263816 hasAuthorship W2893263816A5060836964 @default.
- W2893263816 hasAuthorship W2893263816A5066592371 @default.
- W2893263816 hasAuthorship W2893263816A5070619859 @default.
- W2893263816 hasAuthorship W2893263816A5073008745 @default.
- W2893263816 hasAuthorship W2893263816A5084696446 @default.
- W2893263816 hasAuthorship W2893263816A5088650111 @default.
- W2893263816 hasAuthorship W2893263816A5090077382 @default.
- W2893263816 hasConcept C121332964 @default.
- W2893263816 hasConcept C1276947 @default.
- W2893263816 hasConcept C135041427 @default.
- W2893263816 hasConcept C144024400 @default.
- W2893263816 hasConcept C149923435 @default.
- W2893263816 hasConcept C150846664 @default.
- W2893263816 hasConcept C2908647359 @default.
- W2893263816 hasConcept C32891209 @default.
- W2893263816 hasConcept C43481613 @default.
- W2893263816 hasConcept C44870925 @default.
- W2893263816 hasConcept C4839761 @default.
- W2893263816 hasConcept C68271606 @default.
- W2893263816 hasConcept C73329638 @default.
- W2893263816 hasConcept C96141758 @default.
- W2893263816 hasConcept C98444146 @default.
- W2893263816 hasConceptScore W2893263816C121332964 @default.
- W2893263816 hasConceptScore W2893263816C1276947 @default.
- W2893263816 hasConceptScore W2893263816C135041427 @default.
- W2893263816 hasConceptScore W2893263816C144024400 @default.
- W2893263816 hasConceptScore W2893263816C149923435 @default.
- W2893263816 hasConceptScore W2893263816C150846664 @default.
- W2893263816 hasConceptScore W2893263816C2908647359 @default.
- W2893263816 hasConceptScore W2893263816C32891209 @default.
- W2893263816 hasConceptScore W2893263816C43481613 @default.
- W2893263816 hasConceptScore W2893263816C44870925 @default.
- W2893263816 hasConceptScore W2893263816C4839761 @default.
- W2893263816 hasConceptScore W2893263816C68271606 @default.
- W2893263816 hasConceptScore W2893263816C73329638 @default.
- W2893263816 hasConceptScore W2893263816C96141758 @default.
- W2893263816 hasConceptScore W2893263816C98444146 @default.
- W2893263816 hasLocation W28932638161 @default.
- W2893263816 hasOpenAccess W2893263816 @default.
- W2893263816 hasPrimaryLocation W28932638161 @default.
- W2893263816 hasRelatedWork W1967146124 @default.
- W2893263816 hasRelatedWork W1985786875 @default.
- W2893263816 hasRelatedWork W2093294533 @default.
- W2893263816 hasRelatedWork W2230578375 @default.
- W2893263816 hasRelatedWork W2278589840 @default.
- W2893263816 hasRelatedWork W2637629984 @default.
- W2893263816 hasRelatedWork W2803326584 @default.
- W2893263816 hasRelatedWork W2951307536 @default.
- W2893263816 hasRelatedWork W3013284073 @default.
- W2893263816 hasRelatedWork W3041794221 @default.
- W2893263816 hasRelatedWork W3098039553 @default.
- W2893263816 hasRelatedWork W3098804876 @default.
- W2893263816 hasRelatedWork W3100163713 @default.
- W2893263816 hasRelatedWork W3100264327 @default.
- W2893263816 hasRelatedWork W3100471876 @default.
- W2893263816 hasRelatedWork W3103937042 @default.
- W2893263816 hasRelatedWork W3113701977 @default.
- W2893263816 hasRelatedWork W3121494415 @default.
- W2893263816 hasRelatedWork W3137184110 @default.
- W2893263816 hasRelatedWork W3211675215 @default.
- W2893263816 isParatext "false" @default.