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arXiv · 2606.20308

Evidence for candidate X-ray pulsations from the ultraluminous X-ray source NGC 7456 ULX-1

Yuanle Yao·Xiang-Dong Li·Xiao-Jie Xu
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Abstract

We report evidence for a candidate pulsational signal at $\sim0.22$~Hz from NGC7456 ULX-1, a previously identified ultraluminous X-ray source (ULX). The signal is identified in the 2023 XMM-Newton observation using independent timing techniques including accelerated searches, $Z^2_n$ statistics, and an orbital-demodulation analysis designed to restore phase coherence in the presence of binary motion. The candidate pulsation frequency drift within the observation suggests rapid spin evolution driven by accretion torque. We further estimate the surface dipole magnetic field strength to be $B\sim 10^{12}-10^{14}$ G. These results provide evidence that NGC7456 ULX-1 may host an accreting neutron star, although confirmation with independent datasets or additional observations is required.

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Yuanle Yao, Xiang-Dong Li, Xiao-Jie Xu. 2026-06-18. Evidence for candidate X-ray pulsations from the ultraluminous X-ray source NGC 7456 ULX-1. https://arxiv.org/abs/2606.20308

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