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arXiv · 2404.02061

SRG/ART-XC Galactic Bulge deep survey. I. Maximum likelihood source detection algorithm for X-ray surveys

A. Semena·A. Vikhlinin·I. Mereminskiy·A. Lutovinov·A. Tkachenko·I. Lapshov·R. Burenin
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Abstract

We describe an X-ray source detection method entirely based on the maximum likelihood analysis, in application to observations with the ART-XC telescope onboard the Spectrum Roentgen Gamma observatory. The method optimally combines the data taken at different conditions, a situation commonly found in scanning surveys or mosaic observations with a telescope with a significant off-axis PSF distortion. The method can be naturally extended to include additional information from the X-ray photon energies, detector grades, etc. The likelihood-based source detection naturally results in a stable and uniform definition of detection thresholds under different observing conditions (PSF, background level). This greatly simplifies the statistical calibration of the survey needed to, e.g., obtain the $\log N - \log S$ distribution of detected sources or their luminosity function. The method can be applied to the data from any imaging X-ray telescope.

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A. Semena, A. Vikhlinin, I. Mereminskiy, A. Lutovinov, A. Tkachenko, I. Lapshov, R. Burenin. 2024-04-02. SRG/ART-XC Galactic Bulge deep survey. I. Maximum likelihood source detection algorithm for X-ray surveys. https://arxiv.org/abs/2404.02061

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