Detection of Quasi-periodic Oscillations in SGR 150228213

TL;DR

This paper reports the detection of high-frequency quasi-periodic oscillations in a short magnetar burst, providing new insights into magnetar burst mechanisms and their potential connection to fast radio bursts.

Contribution

It presents the first detection of QPOs in a short magnetar burst, expanding the understanding of magnetar oscillations beyond giant flares.

Findings

Detected ~110 Hz and ~60 Hz QPOs with 3.35σ confidence

No QPOs detected in other bursts from the same magnetar

Associated a repeating fast radio burst with the magnetar burst

Abstract

The detection of quasi-periodic oscillations (QPOs) in magnetar giant flares (GFs) has brought a new perspective to study the mechanism of magnetar bursts. Due to the scarcity of GFs, searching QPOs from magnetar short bursts is reasonable. Here we report the detection of a high frequency QPO at approximately 110 Hz and a wide QPO at approximately 60 Hz in a short magnetar burst SGR 150228213, with a confidence level of 3.35$\sigma$. This burst was initially attributed to 4U 0142+61 by $Fermi$/GBM on location, but we haven't detected such QPOs in other bursts from this magnetar. We also found that there was a repeating fast radio burst associated with SGR 150228213 on location. Finally, we discuss the possible origins of SGR 150228213.