SIMBAD references

A possible quasi-periodic oscillation (QPO) at frequency 7.045 × 10^–5 Hz is found in the narrow-line Seyfert 1 galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April 11. We find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3-10 keV band by using the method of the Lomb-Scargle Periodogram, the Weighted Wavelet Z-transform and the REDFIT. We analyze the data in 0.3-0.6 keV, 0.6-1 keV, 1-3 keV and 3-10 keV energy bands, and find obvious QPO signals at 0.3-0.6 keV and 1-3 keV bands. We then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^–5 Hz, and use a model to fit them. We find that the QPO signal mainly comes from the X-ray hot corona.