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arXiv · 2203.11531

SRGz: building an optical cross-match model for the X-ray SRG/eROSITA sources using the Lockman Hole data

M. I. Belvedersky·A. V. Meshcheryakov·M. R. Gilfanov·P. S. Medvedev
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Abstract

We present a probabilistic model built for the optical cross-match between the SRG/eROSITA X-ray sources and photometric data from the DESI Legacy Imaging Surveys. The model relies both on positional and photometric information on optical objects nearby X-ray sources and allows performing selection with precision and recall $\approx94$% (for $F_{\rm X,0.5-2}>10^{-14}$ erg/s/cm$^2$). With this model, we calibrated positional error of the SRG/eROSITA sources detected in the Lockman Hole: $\sigma_{\rm corr} = 0.87\sqrt{ \sigma_{\rm det}^{2.53} + 1.12^2}$. The model will become a part of the SRGz system for data analysis of the X-ray data obtained from the all-sky SRG/eROSITA survey.

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M. I. Belvedersky, A. V. Meshcheryakov, M. R. Gilfanov, P. S. Medvedev. 2022-03-22. SRGz: building an optical cross-match model for the X-ray SRG/eROSITA sources using the Lockman Hole data. https://arxiv.org/abs/2203.11531

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