A uniform asymptotic expansion for the incomplete gamma function

We describe a new uniform asymptotic expansion for the incomplete gamma function Γ( a, z) valid for large values of z. This expansion contains a complementary error function of an argument measuring transition across the point z= a (which is different from that in the well-known uniform expansion fo...

Full description

Saved in:
Bibliographic Details
Published inJournal of computational and applied mathematics Vol. 148; no. 2; pp. 323 - 339
Main Author Paris, R.B.
Format Journal Article
LanguageEnglish
Published Amsterdam Elsevier B.V 15.11.2002
Elsevier
Subjects
Online AccessGet full text

Cover

Loading…
More Information
Summary:We describe a new uniform asymptotic expansion for the incomplete gamma function Γ( a, z) valid for large values of z. This expansion contains a complementary error function of an argument measuring transition across the point z= a (which is different from that in the well-known uniform expansion for large a of Temme), with easily computable coefficients that do not involve a removable singularity at z= a. Our expansion is, however, valid in a smaller domain of the parameters than that of Temme. Numerical examples are given to illustrate the accuracy of the expansion.
Bibliography:ObjectType-Article-2
SourceType-Scholarly Journals-1
ObjectType-Feature-1
content type line 23
ISSN:0377-0427
1879-1778
DOI:10.1016/S0377-0427(02)00553-8