Abstract for Proposal 088188
Confirming an eROSITA & Swift-selected Close Supermassive Black Hole Binary
In performing multiple all-sky X-ray surveys and monitoring several
hundred thousand AGN every six months eROSITA has the capability
to identify exceptional AGN with a periodic X-ray flux signal. These
objects are interpreted as close supermassive black hole binary (SMBHB)
candidates. Additional Swift data between the half-a-year eROSITA
data will be used first to confirm i) the periodic signal and ii) the
accurate period. Only in a such case, will we initiate our XMM-Newton
pilot study program requesting one ToO observation of 120 ks for the best
eROSITA/Swift-selected periodic AGN. The detection of a double-peaked
Fe K$alpha$ emission will establish the SMBHB nature of the object. Due
to the eROSITA observing pattern, we can identify the closest-distance
pairs ever discovered.
Details on Observing Strategy and Trigger Criteria
criteria: i) periodic signal with eROSITA and confirmed with Swift
or NICER, ii) expected flux during XMM observation f0.2-5 keV ~10-12
cgs; reaction time: up to 15 days; observing strategy: EPIC pn, large
window mode