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Using the popular Langer?Polyakov?Coleman instanton method, the
decay rate of metastable states and the level splitting of energy,
due to tunneling of some one-dimensional potentials have been
calculated. The operators appearing in the prefactor of the decay
rate or the level splitting of energy of these kinds of potentials
possess the shape invariance symmetry, hence using this property,
the determinant of these operators have been calculated
analytically via heat kernel method.
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