Kavli Affiliate: Erin Kara
| First 5 Authors: Margherita Giustini, Giovanni Miniutti, Riccardo Arcodia, Adelle Goodwin, Kate D. Alexander
| Summary:
Quasi-periodic eruptions (QPEs) are an extreme X-ray variability phenomenon
associated with low-mass supermassive black holes. First discovered in the
nucleus of the galaxy GSN 069, they have been so far securely detected in five
other galaxies, including RX J1301.9+2747. When detected, the out-of-QPE
emission (quiescence) is consistent with the high-energy tail of thermal
emission from an accretion disk. We present the X-ray and radio properties of
RX J1301.9+2747, both in quiescence and during QPEs. We analyse X-ray data
taken during five XMM-Newton observations between 2000 and 2022. The last three
observations were taken in coordination with radio observations with the Karl
G. Jansky Very Large Array. We also make use of EXOSAT, ROSAT, and Chandra
archival observations taken between 1983 and 2009. XMM-Newton detected 34 QPEs
of which 8 have significantly lower amplitudes than the others. No correlated
radio/X-ray variability was observed during QPEs. In terms of timing
properties, the QPEs in RX J1301.9+2747 do not exhibit the striking regularity
observed in the discovery source GSN 069. In fact there is no clear repetition
pattern between QPEs: the average time separation between their peaks is about
four hours, but it can be as short as one, and as long as six hours. The QPE
spectral properties of RX J1301.9+2747 as a function of energy are however very
similar to those of GSN 069 and of other QPE sources. The quiescent emission of
RX J1301.9+2747 is more complex than that of GSN 069, as it requires a soft
X-ray excess-like component in addition to the thermal emission from the
accretion disk. Its long-term X-ray quiescent flux variations are of
low-amplitude and not strictly monotonic, with a general decay over $sim 22$
years. We discuss our observational results in terms of some of the ideas and
models that have been proposed so far for the physical origin of QPEs.
| Search Query: ArXiv Query: search_query=au:”Erin Kara”&id_list=&start=0&max_results=3