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arXiv · 2112.02794

The Spin of New Black Hole Candidate: MAXI J1803-298 Observed by NuSTAR and NICER

Ye Feng·Xueshan Zhao·Yufeng Li·Lijun Gou·Nan Jia·Zhenxuan Liao·Yuan Wang
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Abstract

MAXI J1803-298, a newly-discovered Galactic transient and black hole candidate, was first detected by \emph{MAXI}/GSC on May 1st, 2021. In this paper, we present a detailed spectral analysis of MAXI J1803-298. Utilizing the X-ray reflection fitting method, we perform a joint fit to the spectra of MAXI J1803-298, respectively, observed by \emph{NuSTAR} and \emph{NICER}/XTI on the same day over the energy range between 0.7-79.0 keV, and found its spin (and the inclination angle i) can be constrained to be close to an extreme value, 0.991 ($i\sim$ $70 ^{\circ}$), at 68\% confidence interval. The results suggest that MAXI J1803-298 may be a fast-rotating black hole with a large inclination angle.

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Ye Feng, Xueshan Zhao, Yufeng Li, Lijun Gou, Nan Jia, Zhenxuan Liao, Yuan Wang. 2021-12-06. The Spin of New Black Hole Candidate: MAXI J1803-298 Observed by NuSTAR and NICER. https://doi.org/10.1093/mnras%2Fstac1868

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