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تسجيل مستخدم جديدBounds on WIMP dark matter from galaxy clusters at low redshift
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The study of the cross-correlation angular power spectrum between gravitational tracers and electromagnetic signals can be a powerful tool to constrain Dark Matter (DM) microscopic properties. In this work we correlate Fermi diffuse g-ray maps with catalogues of galaxy clusters. To emphasize the sensitivity to a DM signal, we select clusters at low-redshift $0<z<0.2$ and with large-halo mass $M_{500}>10^{13}M_odot$. The analysis is performed with four catalogues in different wavebands, including infrared, optical and X-rays. No evidence for a DM signal is identified. On the other hand, we derive competitive bounds: the thermal cross-section is excluded at 95% C.L. for DM masses below 20 GeV and annihilation in the $tau^+-tau^-$ channel.
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