{"work":{"id":"970da27d-b031-4896-bd5c-6b2ba3963c59","openalex_id":"https://openalex.org/W2950529756","doi":"10.1088/0004-637x/788/1/48","arxiv_id":"1310.2241","raw_key":null,"title":"The Man Behind the Curtain: X-rays Drive the UV through NIR Variability in the 2013 AGN Outburst in NGC 2617","authors":[{"given":"B. J.","family":"Shappee","sequence":"first","affiliation":[]},{"ORCID":"https://orcid.org/0000-0003-0943-0026","given":"J. L.","family":"Prieto","sequence":"additional","affiliation":[],"authenticated-orcid":false},{"ORCID":"https://orcid.org/0000-0002-9961-3661","given":"D.","family":"Grupe","sequence":"additional","affiliation":[],"authenticated-orcid":false},{"given":"C. S.","family":"Kochanek","sequence":"additional","affiliation":[]},{"given":"K. Z.","family":"Stanek","sequence":"additional","affiliation":[]},{"given":"G.","family":"De Rosa","sequence":"additional","affiliation":[]},{"given":"S.","family":"Mathur","sequence":"additional","affiliation":[]},{"given":"Y.","family":"Zu","sequence":"additional","affiliation":[]},{"given":"B. M.","family":"Peterson","sequence":"additional","affiliation":[]},{"given":"R. W.","family":"Pogge","sequence":"additional","affiliation":[]},{"given":"S.","family":"Komossa","sequence":"additional","affiliation":[]},{"given":"M.","family":"Im","sequence":"additional","affiliation":[]},{"given":"J.","family":"Jencson","sequence":"additional","affiliation":[]},{"given":"T.W-S.","family":"Holoien","sequence":"additional","affiliation":[]},{"given":"U.","family":"Basu","sequence":"additional","affiliation":[]},{"given":"J. F.","family":"Beacom","sequence":"additional","affiliation":[]},{"given":"D. M.","family":"Szczygieł","sequence":"additional","affiliation":[]},{"given":"J.","family":"Brimacombe","sequence":"additional","affiliation":[]},{"given":"S.","family":"Adams","sequence":"additional","affiliation":[]},{"given":"A.","family":"Campillay","sequence":"additional","affiliation":[]},{"given":"C.","family":"Choi","sequence":"additional","affiliation":[]},{"given":"C.","family":"Contreras","sequence":"additional","affiliation":[]},{"given":"M.","family":"Dietrich","sequence":"additional","affiliation":[]},{"given":"M.","family":"Dubberley","sequence":"additional","affiliation":[]},{"given":"M.","family":"Elphick","sequence":"additional","affiliation":[]},{"given":"S.","family":"Foale","sequence":"additional","affiliation":[]},{"given":"M.","family":"Giustini","sequence":"additional","affiliation":[]},{"given":"C.","family":"Gonzalez","sequence":"additional","affiliation":[]},{"given":"E.","family":"Hawkins","sequence":"additional","affiliation":[]},{"ORCID":"https://orcid.org/0000-0003-4253-656X","given":"D. A.","family":"Howell","sequence":"additional","affiliation":[],"authenticated-orcid":false},{"given":"E. Y.","family":"Hsiao","sequence":"additional","affiliation":[]},{"given":"M.","family":"Koss","sequence":"additional","affiliation":[]},{"ORCID":"https://orcid.org/0000-0002-3809-0051","given":"K. M.","family":"Leighly","sequence":"additional","affiliation":[],"authenticated-orcid":false},{"ORCID":"https://orcid.org/0000-0003-2535-3091","given":"N.","family":"Morrell","sequence":"additional","affiliation":[],"authenticated-orcid":false},{"given":"D.","family":"Mudd","sequence":"additional","affiliation":[]},{"given":"D.","family":"Mullins","sequence":"additional","affiliation":[]},{"given":"J. M.","family":"Nugent","sequence":"additional","affiliation":[]},{"given":"J.","family":"Parrent","sequence":"additional","affiliation":[]},{"given":"M. M.","family":"Phillips","sequence":"additional","affiliation":[]},{"given":"G.","family":"Pojmanski","sequence":"additional","affiliation":[]},{"given":"W.","family":"Rosing","sequence":"additional","affiliation":[]},{"given":"R.","family":"Ross","sequence":"additional","affiliation":[]},{"given":"D.","family":"Sand","sequence":"additional","affiliation":[]},{"given":"D. M.","family":"Terndrup","sequence":"additional","affiliation":[]},{"given":"S.","family":"Valenti","sequence":"additional","affiliation":[]},{"given":"Z.","family":"Walker","sequence":"additional","affiliation":[]},{"given":"Y.","family":"Yoon","sequence":"additional","affiliation":[]}],"authors_text":"Shappee, B","year":2013,"venue":"astro-ph.HE","abstract":"After the All-Sky Automated Survey for SuperNovae (ASAS-SN) discovered a significant brightening of the inner region of NGC 2617, we began a ~70 day photometric and spectroscopic monitoring campaign from the X-ray through near-infrared (NIR) wavelengths. We report that NGC 2617 went through a dramatic outburst, during which its X-ray flux increased by over an order of magnitude followed by an increase of its optical/ultraviolet (UV) continuum flux by almost an order of magnitude. NGC 2617, classified as a Seyfert 1.8 galaxy in 2003, is now a Seyfert 1 due to the appearance of broad optical emission lines and a continuum blue bump. Such \"changing look Active Galactic Nuclei (AGN)\" are rare and provide us with important insights about AGN physics. Based on the Hbeta line width and the radius-luminosity relation, we estimate the mass of central black hole to be (4 +/- 1) x 10^7 M_sun. When we cross-correlate the light curves, we find that the disk emission lags the X-rays, with the lag becoming longer as we move from the UV (2-3 days) to the NIR (6-9 days). Also, the NIR is more heavily temporally smoothed than the UV. This can largely be explained by a simple model of a thermally emitting thin disk around a black hole of the estimated mass that is illuminated by the observed, variable X-ray fluxes.","external_url":"https://arxiv.org/abs/1310.2241","cited_by_count":1701,"metadata_source":"pith","metadata_fetched_at":"2026-07-08T19:55:33.393462+00:00","pith_arxiv_id":"1310.2241","created_at":"2026-05-08T20:44:10.125283+00:00","updated_at":"2026-07-11T11:50:26.030339+00:00","title_quality_ok":true,"display_title":"J., Prieto , J","render_title":"J., Prieto , J"},"hub":{"state":{"work_id":"970da27d-b031-4896-bd5c-6b2ba3963c59","tier":"hub","tier_reason":"10+ Pith inbound or 1,000+ external citations","pith_inbound_count":42,"external_cited_by_count":1701,"distinct_field_count":5,"first_pith_cited_at":"2019-06-27T07:19:18+00:00","last_pith_cited_at":"2026-07-07T08:10:09+00:00","author_build_status":"not_needed","summary_status":"needed","contexts_status":"needed","graph_status":"needed","ask_index_status":"not_needed","reader_status":"not_needed","recognition_status":"not_needed","updated_at":"2026-08-22T15:59:28.111038+00:00","tier_text":"hub"},"tier":"hub","role_counts":[{"context_role":"background","n":3},{"context_role":"method","n":1}],"polarity_counts":[{"context_polarity":"background","n":2},{"context_polarity":"unclear","n":1},{"context_polarity":"use_method","n":1}],"runs":{},"summary":{},"graph":{},"authors":[]}}