Abstract

We study the distribution of zeros of general solutions of the Airy and Bessel equations in the complex plane. Our results characterize the patterns followed by the zeros for any solution, in such a way that if one zero is known it is possible to determine the location of the rest of zeros.

Highlights

  • Airy and Bessel functions are important examples of special functions satisfying second order lineal ODEs

  • We begin with a description of the anti-Stokes lines (ASLs) and Stokes line (SL), followed by an analysis of the distribution of the zeros for the general solution cos αAi(z) + sin αBi(z); this analysis will be important in the description of the zeros of general Bessel functions cos αJν(z) − sin αYν (z)

  • Differently from the Airy case, asymptotics for large z will be not enough to obtain a complete picture of the distribution of zeros, and we will need to consider uniform asymptotic approximations for large order [9] in order to describe some of the zeros

Read more

Summary

Introduction

Airy and Bessel functions are important examples of special functions satisfying second order lineal ODEs. The use of asymptotics (both of Poincare type and uniform asymptotics for large orders in the case of Bessel functions) will provide more detailed and quantitative information These results will characterize the possible patterns followed by the zeros for any solution, leading to the development of methods which are able to compute safely and accurately all the zeros in a given region and having as only input data the location of just one zero (and the order for the case of the Bessel equation). These are the so-called anti-Stokes lines (ASLs) in the LG approximation. For the zeros of y′(z), as we will see, the approximation that they are on ASL curves given by (2) (and equivalently 4) will be in general sufficiently accurate. The numerical method for complex zeros of y(z) given in [14] is successful for the zeros of y′(z) with only a simple change in the iteration function of the fixed point method

Zeros of Airy functions
Anti-Stokes lines for the Airy equation in the LG approximation
Zeros approaching asymptotically the negative real axis
Zeros of Bessel functions
Stokes and anti-Stokes lines for the Bessel equation in the LG approximation
Zeros of Hankel functions
Zeros close to the eye-shaped region or inside the eye-shaped region
Algorithms
Algorithm for Airy functions
Algorithm for Bessel functions
Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.