Bounds on Neutrino-Scalar Yukawa Coupling
نویسندگان
چکیده
General neutrino-scalar couplings appear in many extensions of Standard Model. We can probe these neutrino-scalar couplings by leptonic decay of mesons and from heavy neutrino search. Our analysis improves the present limits to |ge| < 1.9 × 10−6 and |gμ| < 1.9 × 10−7 at 90% C.L. for massless scalars. For massive scalars we found for the first time the constraints for g α couplings to be 10−6−10−1 respectively for scalar masses between up 100 MeV and we have no limits for masses above 300 MeV.
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