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arXiv · 2505.11322

Intriguing nature of AM Her type candidate CXOU J204734.8+300105

Rahul Sharma·Chetana Jain·Biswajit Paul·Anjan Dutta·Vikram Rana
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Abstract

The detection and characterization of periodic X-ray signals are crucial for identifying new compact objects and studying the mechanisms powering their emission. We report on the timing and spectral variability of CXOU J204734.8+300105, a proposed eclipsing polar-type cataclysmic variable (CV) candidate. This source has been observed once with Chandra and twice with XMM-Newton, revealing several intriguing and conflicting features in its X-ray emission. The Chandra observation showed a periodicity of $\sim$6000 s with an eclipse-like feature. The X-ray light curve from 2017 XMM-Newton observation showed a period of $\sim$2000 seconds without any apparent eclipse, while the simultaneous optical light curve from OM showed a period of $\sim$6000 seconds. This variability raises questions about the true nature of the source. Spectral analysis indicates a multi-component emission and emission lines due to Fe. The spectral characteristics are consistent with those observed in other CV systems. Additionally, we identified optical and near-infrared counterparts from various catalogues. Our findings suggest a dynamic and evolving accretion environment of CXOU J204734.8+300105.

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Rahul Sharma, Chetana Jain, Biswajit Paul, Anjan Dutta, Vikram Rana. 2025-05-16. Intriguing nature of AM Her type candidate CXOU J204734.8+300105. https://doi.org/10.3847/1538-4357%2Faddc5b

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