2024/06/18 by Wang, Xin-Lei, Yan, Zhen, Xie, Fu-Guo +2
#FOS: Physical sciences #High Energy Astrophysical Phenomena (astro-ph.HE)
paper · doi:10.48550/arxiv.2406.12477
Based on the Insight-HXMT archival data, we have detected a new atypical low-frequency quasi-periodic oscillation (LFQPO) in the black hole X-ray binary MAXI J1348-630. The new LFQPO is detected in all the three instruments of Insight-HXMT with a combined significance of 3--5 σ, covering a wide energy range of 1--100 keV. The fractional root-mean-square (RMS) seems decrease with energy. It exclusively appears in the hard state during both the main and mini outburst, spanning an X-ray intensity range by a factor of 10, and a very narrow hardness range. The frequency of this new type of LFQPO is moderately stable, in the range of 0.08--0.15 Hz. We discussed different models for the LFQPO, and found none is able to explain the observed properties of this new type of LFQPO.