Timing analysis of the new black hole candidate MAXI J1803−298 with Insight–HXMT and NICER

Abstract

We present the timing analysis results of MAXI J1803−298, a black hole candidate, during its 2021 outburst using data obtained from the Insight-HXMT and NICER telescopes. Our analysis reveals that the source undergoes a state transition from the low/hard state to the hard intermediate state, followed by the soft intermediate state, and ultimately reaching the high/soft state. We searched for the quasi-periodic oscillations (QPOs) and studied the characteristics of the outburst. At the beginning of the outburst, the source was in the hard state, many type-C QPOs were seen in the Insight-HXMT data, and the frequency of these QPOs increased from ∼0.16 to 2.6 Hz. Our analysis of the type-C QPOs’ rms–frequency relationship indicates a turning point in the frequency. We also analyzed the phase lag versus frequency and energy relationship and deduced that the source likely has a high inclination angle, consistent with previous research. The observed rms and phase lag features in type-C QPOs could be explained by the Lense-Thirring precession model, while the alternatives would be still viable. The lag spectrum of type-B QPO exhibits a ‘U-shaped’ pattern similar to many other sources, and the type-B QPOs’ rms increase as the energy rises. This phenomenon can be explained by the dual-corona model.

Timing and Spectral Analysis of the Black Hole X-Ray Binary MAXI J1803-298 with Insight-HXMT Data

“…In Figure 6, the QPO rms in the 1-10 keV energy band presents an opposite decreasing trend over frequency compared to the QPO rms in the 10-28 keV and 28-100 keV band, which is consistent with the result of Zhu et al (2023). Since the diskbb component is mainly present at energies below ∼10 keV, the type-C QPOs must be correlated with the Comptonized component.…”

“…Type-C and type-B QPOs were detected in the PDS of MAXI J1803-298 (Bult et al 2021;Ubach et al 2021). Zhu et al (2023) analyzed both QPO signals using Insight-Hard X-ray Modulation Telescope (Insight-HXMT) and NICER data, respectively. The type-C QPOs they observed are in the LHS, and are detected up to 60 keV, with frequency from ∼0.16 to 2.6 Hz.…”

“…Insight-HXMT has observed the complete evolution of MAXI J1803-298 from the LHS to the HSS in its 2021 outburst. We study the timing and spectral properties using the whole Insight-HXMT data to identify the states and the presence of QPO signals (see Zhu et al 2023). In Section 2, we introduce the data reduction strategy of Insight-HXMT observations and the basic analysis methods.…”

Energy Dependence of the Low-frequency Quasiperiodic Oscillations in Swift J1727.8–1613

“…The study of EXO 1846C031 using observations from the Insight-HXMT similarly identifies a transition frequency of approximately 2 Hz, with the rmsfrequency morphology in the LE, ME, and HE bands resembling our findings (Liu et al 2021). In the study of MAXI J1803-298, similar results were observed, indicating a comparable transition frequency (Zhu et al 2023). Shui et al (2023) present a systematic analysis of type C QPO observations of H1743-322.…”

“…In the QPO rms amplitude-energy relationship, the observed shapes in Figure 8 is similar to that of many other sources, like MAXI J1803−298 (Zhu et al 2023), MAXI J1535−571 (Huang et al 2018;Kong et al 2020;Garg et al 2022), XTE J1550−564 (Li et al 2013a), and MAXI J1631−479 (Bu et al 2021). You et al (2018) computed the fractional rms spectrum of the QPO within the framework of the L-T precession model (Ingram et al 2009), aiming to investigate energy-dependent variability during the state transition.…”