Equation Icon  ( ) ( ) √ --2----2 √ --2----2 φm (t) = Am+ exp +i m + k t + Am − exp − i m + k t , (36 ) f (y ) = e2y∕ℓ[B J (m ℓey∕ℓ) + C Y (m ℓey∕ℓ)] . (37 ) m m 2 m 2