Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Title A name given to the resource Faculty Publications Article Faculty Publications -Articles Dublin Core The Dublin Core metadata element set is common to all Omeka records, including items, files, and collections. For more information see, http://dublincore.org/documents/dces/. Creator An entity primarily responsible for making the resource Roy, Dilip Kumar; Barua, Samuzal; Misra, Ranjeev; Sarma, Rathin; Jithesh, V. Title A name given to the resource Tracing Fe K X-Ray Reverberation Lag in the Energy-resolved Spectra of Narrow-line Seyfert 1 Galaxy Ton S180 Date A point or period of time associated with an event in the lifecycle of the resource 01-01-2026 Source A related resource from which the described resource is derived Astrophysical Journal;Volume;1000;Issue;1;Article No.;107; Identifier An unambiguous reference to the resource within a given context <a href="https://doi.org/10.3847/1538-4357/ae474a" target="_blank" rel="noreferrer noopener">https://doi.org/10.3847/1538-4357/ae474a</a> <br /><br /><a href="https://www.scopus.com/pages/publications/105034634865?origin=resultslist" target="_blank" rel="noreferrer noopener">https://www.scopus.com/pages/publications/105034634865?origin=resultslist</a> Coverage The spatial or temporal topic of the resource, the spatial applicability of the resource, or the jurisdiction under which the resource is relevant Roy D.K., Department of Physics, Rabindranath Tagore University, Assam, Hojai, 782435, India; Barua S., Shanghai Astronomical Observatory, Chinese Academy of Sciences, 80 Nandan Road, Shanghai, 200030, China; Misra R., Inter-University Centre for Astronomy and Astrophysics (IUCAA), PB No. 4, Ganeshkhind, Pune, 411007, India; Sarma R., Department of Physics, Rabindranath Tagore University, Assam, Hojai, 782435, India; Jithesh V., Department of Physics and Electronics, Christ University, Hosur Main Road, Bengaluru, 560029, India Description An account of the resource We report the Fe K relativistic reverberation feature for the first time in the narrow-line Seyfert 1 galaxy Ton S180. Using a long observation from XMM-Newton we find that the Fe K emission lag peaks at 117 49 s in the lag energy spectrum computed for frequencies (0.3-8.5) 10?4 Hz. The lag amplitude drops to 22.85 14.20 s as the frequency increases to (8.5-30) 10?4 Hz. The time-averaged spectrum of the source shows a relatively narrow Fe K line at ?6.4 keV, indicating a low black hole spin ( a = 0 . 4 3 ? 0.14 + 0.10 ) based on the reflection modeling. We perform general relativistic transfer function modeling of the lag energy spectra individually. This provides an independent timing-based measure of the spin at a = 0.3 0 ? 0.17 + 0.34 , a black hole mass M BH = 0.2 9 ? 0.16 + 0.01 1 0 8 M ? , comparable to the previous measurement, and a coronal height h = 2.5 9 ? 0.33 + 5.17 r g . Further, we observe that the Fe K lag and the black hole mass fit well in the linear lag-mass relation shown by other Seyfert 1 galaxies. 2026. The Author(s). Published by the American Astronomical Society. Publisher An entity responsible for making the resource available American Astronomical Society Relation A related resource ISSN: 0004637X; Language A language of the resource English Type The nature or genre of the resource Article Rights Information about rights held in and over the resource All Open Access; Gold Open Access; Green Open Access Format The file format, physical medium, or dimensions of the resource online