Volume 636, April 2020
|Number of page(s)||8|
|Section||Letters to the Editor|
|Published online||09 April 2020|
Letter to the Editor
X-ray quasi-periodic eruptions from the galactic nucleus of RX J1301.9+2747
Centro de Astrobiología (CSIC-INTA), Camino Bajo del Castillo s/n, Villanueva de la Cañada, 28692 Madrid, Spain
2 Telespazio-Vega UK for ESA, Operations Department, European Space Astronomy Centre (ESAC), Camino Bajo del Castillo s/n, Villanueva de la Cañada, 28692 Madrid, Spain
Accepted: 6 March 2020
Following the recent discovery of X-ray quasi-periodic eruptions (QPEs) coming from the nucleus of the galaxy GSN 069, here we report on the detection of QPEs in the active galaxy named RX J1301.9+2747. QPEs are rapid and recurrent increases of the X-ray count-rate by more than one order of magnitude with respect to a stable quiescent level. During a XMM-Newton observation lasting 48 ks that was performed on 30 and 31 May 2019, three strong QPEs lasting about half an hour each were detected in the light curves of RX J1301.9+2747. The first two QPEs are separated by a longer recurrence time (about 20 ks) compared to the second and third (about 13 ks). This pattern is consistent with the alternating long-short recurrence times of the GSN 069 QPEs, although the difference between the consecutive recurrence times is significantly smaller in GSN 069. Longer X-ray observations will better clarify the temporal pattern of the QPEs in RX J1301.9+2747 and will allow a detailed comparison with GSN 069 to be performed. The X-ray spectral properties of QPEs in the two sources are remarkably similar, with QPEs representing fast transitions from a relatively cold and likely disk-dominated state to a state that is characterized by a warmer emission similar to the so-called soft X-ray excess, a component that is almost ubiquitously seen in the X-ray spectra of unobscured, radiatively efficient active galaxies. Previous X-ray observations of RX J1301.9+2747 in 2000 and 2009 strongly suggest that QPEs have been present for at least the past 18.5 yr. The detection of QPEs from a second galactic nucleus after GSN 069 rules out contamination by a Galactic source in both cases, such that QPEs ought to be considered a novel extragalactic phenomenon associated with accreting supermassive black holes.
Key words: galaxies: active / galaxies: nuclei / quasars: general / quasars: supermassive black holes / X-rays: individuals: RX J1301.9+2747
© ESO 2020
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.