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تسجيل مستخدم جديدBlast from the past: constraints from the CHARM experiment on Heavy Neutral Leptons with tau mixing
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We re-analyze the results of the searches for Heavy Neutral Leptons (HNLs) by the CHARM experiment. We study HNL decay channel $Nto e^{+}e^{-} u/mu^{+}mu^{-} u$ and show that, in addition to the constraints on the HNLs mixings with $ u_e$ or $ u_{mu}$, the same data also implies limits on the HNLs that mix only with $ u_{tau}$ and have masses in the range $380 text{ MeV}<m_{N}lesssim 1.6text{ GeV}$ - the region in the parameter space that was considered in the literature as a target for HNLs searches.
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