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Evidence for variability time-scale-dependent UV/X-ray delay in Seyfert 1 AGN NGC 7469
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dc.contributor.author | Pahari, Mayukh | |
dc.contributor.author | McHardy, Ian M. | |
dc.contributor.author | Vincentelli, Federico | |
dc.contributor.author | Cackett, Edward M. | |
dc.contributor.author | Peterson, Bradley M. | |
dc.contributor.author | Goad, Michael R. | |
dc.contributor.author | Gültekin, Kayhan | |
dc.contributor.author | Horne, Keith | |
dc.date.accessioned | 2020-08-20T11:30:03Z | |
dc.date.available | 2020-08-20T11:30:03Z | |
dc.date.issued | 2020-05 | |
dc.identifier | 269474355 | |
dc.identifier | 3c403198-ed18-4ffe-9c6f-f99a92bb7b5c | |
dc.identifier | 000535882100075 | |
dc.identifier | 85101306792 | |
dc.identifier.citation | Pahari , M , McHardy , I M , Vincentelli , F , Cackett , E M , Peterson , B M , Goad , M R , Gültekin , K & Horne , K 2020 , ' Evidence for variability time-scale-dependent UV/X-ray delay in Seyfert 1 AGN NGC 7469 ' , Monthly Notices of the Royal Astronomical Society , vol. 494 , no. 3 , pp. 4057-4068 . https://doi.org/10.1093/mnras/staa1055 | en |
dc.identifier.issn | 0035-8711 | |
dc.identifier.uri | https://hdl.handle.net/10023/20492 | |
dc.description | MP acknowledges Royal Society-SERB Newton International Fellowship support funded jointly by the Royal Society, UK and the Science and Engineering Board of India (SERB) through Newton–Bhabha Fund. IMcH acknowledges support from a Royal Society Leverhulme Trust Research Fellowship LT160006 and from STFC grant ST/M001326/1. EMC gratefully acknowledges support from the National Science Foundation through award number AST-1909199. KH acknowledges support from STFC grant ST/R000824/1. | en |
dc.description.abstract | Using a month-long X-ray light curve from RXTE/PCA and 1.5 month-long UV continuum light curves from IUE spectra in 1220-1970 Å, we performed a detailed time-lag study of the Seyfert 1 galaxy NGC 7469. Our cross-correlation analysis confirms previous results showing that the X-rays are delayed relative to the UV continuum at 1315 Å by 3.49 ± 0.22 d, which is possibly caused by either propagating fluctuation or variable Comptonization. However, if variations slower than 5 d are removed from the X-ray light curve, the UV variations then lag behind the X-ray variations by 0.37 ± 0.14 d, consistent with reprocessing of the X-rays by a surrounding accretion disc. A very similar reverberation delay is observed between Swift/XRT X-ray and Swift/UVOT UVW2, U light curves. Continuum light curves extracted from the Swift/GRISM spectra show delays with respect to X-rays consistent with reverberation. Separating the UV continuum variations faster and slower than 5 d, the slow variations at 1825 Å lag those at 1315 Å by 0.29 ± 0.06 d, while the fast variations are coincident (0.04 ± 0.12 d). The UV/optical continuum reverberation lag from IUE, Swift, and other optical telescopes at different wavelengths are consistent with the relationship: τ ∝ λ4/3, predicted for the standard accretion disc theory while the best-fitting X-ray delay from RXTE and Swift/XRT shows a negative X-ray offset of ∼0.38 d from the standard disc delay prediction. | |
dc.format.extent | 12 | |
dc.format.extent | 1955435 | |
dc.language.iso | eng | |
dc.relation.ispartof | Monthly Notices of the Royal Astronomical Society | en |
dc.subject | Accretion, accretion discs | en |
dc.subject | Black hole physics | en |
dc.subject | Galaxies: individual: NGC 7469 | en |
dc.subject | Galaxies: Seyfert | en |
dc.subject | X-rays: galaxies | en |
dc.subject | QB Astronomy | en |
dc.subject | QC Physics | en |
dc.subject | 3rd-DAS | en |
dc.subject.lcc | QB | en |
dc.subject.lcc | QC | en |
dc.title | Evidence for variability time-scale-dependent UV/X-ray delay in Seyfert 1 AGN NGC 7469 | en |
dc.type | Journal article | en |
dc.contributor.sponsor | Science & Technology Facilities Council | en |
dc.contributor.institution | University of St Andrews. School of Physics and Astronomy | en |
dc.contributor.institution | University of St Andrews. St Andrews Centre for Exoplanet Science | en |
dc.identifier.doi | 10.1093/mnras/staa1055 | |
dc.description.status | Peer reviewed | en |
dc.identifier.url | https://arxiv.org/abs/2004.07901 | en |
dc.identifier.grantnumber | ST/R00824/1 | en |
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