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تسجيل مستخدم جديدSearch for chameleons with CAST
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In this work we present a search for (solar) chameleons with the CERN Axion Solar Telescope (CAST). This novel experimental technique, in the field of dark energy research, exploits both the chameleon coupling to matter ($beta_{rm m}$) and to photons ($beta_{gamma}$) via the Primakoff effect. By reducing the X-ray detection energy threshold used for axions from 1$,$keV to 400$,$eV CAST became sensitive to the converted solar chameleon spectrum which peaks around 600$,$eV. Even though we have not observed any excess above background, we can provide a 95% C.L. limit for the coupling strength of chameleons to photons of $beta_{gamma}!lesssim!10^{11}$ for $1<beta_{rm m}<10^6$.
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