2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/193006We present a calculation of 1/m^2_b corrections to the lifetime differences of B_s mesons ΔΓ_s in the heavy-quark expansion. We find that they are small to significantly affect ΔΓ_s and present the result for lifetime difference including non-perturbative 1/m_b and 1/m_b^2 corrections. We also analyze the generic ΔB = 1 New Physics contributions to ΔΓ_s and provide several examples.21 pages, 6 figuresHigh Energy Physics - Phenomenologytext