(Taylor & Francis, 2022) Ferreira González, Chelo; López García, José Luis; Pérez Sinusía, Ester; Estatistika, Informatika eta Matematika; Institute for Advanced Materials and Mathematics - INAMAT2; Estadística, Informática y Matemáticas; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
A modification of Watson’s lemma for Laplace transforms ∞
0 f(t)
e−zt dt was introduced in [Nielsen, 1906], deriving a new asymptotic
expansion for large |z| with the extra property of being convergent as well. Inspired in that idea, in this paper we derive asymptotic expansions of two-dimensional Laplace transforms F(x, y) := ∞
0
∞
0 f(t,s) e−xt−ys dt ds for large |x| and |y| that are also convergent. The expansions of F(x, y) are accompanied by error bounds.
Asymptotic and convergent expansions of some specialfunctions are
given as illustration.