Lepton Flavour Violating tau and mu decays induced by scalar leptoquark

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We show that the scalar leptoquark Yukawa couplings generate a significant lepton flavour violation. We compute the light scalar leptoquark contributions to the branching ratios (Br) of the lepton flavour violating (LFV) decays ℓ → ℓᵢ ℓⱼ ℓⱼ and ℓ → ℓ′ γ with (i,j = e,μ). We discuss the role of the relevant input parameters to these decay rates which are the Yukawa couplings (hₐℓ) with (a=u,c,t), the light scalar mass Mₛ₁ and the mixing angle 2θLQ. We investigate the experimental limits from (g-2)μ, μ-e conversion and π→ e νₑ, μνμ to get constraint on the input parameter space. We predict that the upper limits on the branching ratios of τ→ ℓᵢ ℓⱼ ℓⱼ can reach the experimental current limits. We also show that it is possible to accommodate both τ→ ℓᵢ ℓⱼ ℓⱼ and τ→ ℓγ branching ratios for certain choices of LQ parameters.