Hostname: page-component-cd9895bd7-dk4vv Total loading time: 0 Render date: 2024-12-25T05:17:24.085Z Has data issue: false hasContentIssue false

On the zeros of the second and third Jackson q-Bessel functions and their associated q-Hankel transforms

Published online by Cambridge University Press:  01 July 2009

M. H. ANNABY
Affiliation:
Department of Mathematics & Physics, Qatar University, P.O. Box 2713 Doha, Qatar. e-mail: [email protected], [email protected]
Z. S. MANSOUR
Affiliation:
Department of Mathematics, Faculty of Science, Cairo University, Giza, Egypt. e-mail: [email protected]

Abstract

We investigate the zeros of q-Bessel functions of the second and third types as well as those of the associated finite q-Hankel transforms. We derive asymptotic relations of the zeros of the q-Bessel functions by comparison with zeros of the theta function. The asymptotics of q-Bessel functions are also given. Zeros of finite q-Hankel transforms of q-summable functions are shown to be real and simple except for a finite number of possible non real zeros. Sufficient conditions are given to guarantee that all zeros are real. We give some applications concerning zeros of combinations of q-Bessel functions.

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Abreu, L. D., Bustoz, J. and Caradoso, J. L.The roots of the third Jackson q-Bessel functions. Internat. J. Math. Math. Sci. 67 (2003), 42414248.CrossRefGoogle Scholar
[2]Annaby, M. H. and Mansour, Z. S.A basic analog of a theorem of pólya. Math. Z. 258 (2008), 363379.CrossRefGoogle Scholar
[3]Annaby, M. H. and Mansour, Z. S.On the zeros of basic finite Hankel transforms. J. Math. Anal. Appl. 323 (2006), 10911103.CrossRefGoogle Scholar
[4]Annaby, M. H., Mansour, Z. S. and Ashour, O. A. On the reality and asymptotics of zeros of finite q-Hankel transforms. J. Approx. Theory (2008), doi:10.1016/j.jat.2008.11.001.CrossRefGoogle Scholar
[5]Bergweiler, W. and Hayman, W. K.Zeros of solutions of a functional equation. Comp. Meth. Func. Theory. 3 (2003), 5578.CrossRefGoogle Scholar
[6]Boas, R. P.Entire Functions (Academic Press, 1954).Google Scholar
[7]Bustoz, J. and Cardoso, J. L.Basic analog of Fourier series on a q-linear grid. J. Approx. Theory. 112 (2001), 154157.CrossRefGoogle Scholar
[8]Chen, Y., Ismail, M. E. H. and Muttalib, K. A.Asymptotics of basic Bessel functions q-Laguerre polynomials. J. Comput. Appl. Math. 54 (1994), 263272.CrossRefGoogle Scholar
[9]Olde Daalhuis, A. B.Asymptotic expansions for q-gamma, q-exponential and q-Bessel functions. J. Math. Anal. Appl. 186 (1994), 896913.CrossRefGoogle Scholar
[10]Gasper, G. and Rahman, M.Basic Hypergeometric Series (Cambridge University Press 2004).CrossRefGoogle Scholar
[11]Hayman, W. K.Subharmonic Functions, II (Academic Press, 1989).Google Scholar
[12]Hayman, W. K.On the zeros of q-bessel function. Contemp. Math. 382 (2005), 205216.CrossRefGoogle Scholar
[13]Ismail, M. E. H.The zeros of basic Bessel functions, the functions J ν+ax(x) and associated orthogonal polynomials. J. Math. Anal. Appl. 86 (1982), 1119.CrossRefGoogle Scholar
[14]Ismail, M. E. HClassical and Quantum Orthogonal Polynomials in One Variable. (Cambridge University Press, 2005).CrossRefGoogle Scholar
[15]Ismail, M. E. H. and Zhang, C.Zeros of entire functions and a problem of Ramanujan. Adv. Math. 209 (2007), 363380.CrossRefGoogle Scholar
[16]Jackson, F. H.A basic-sine and cosine with sympolical solutions of certain differential equations. proc. Edinburgh Math. Soc. 22 (1903–1904), 2834.CrossRefGoogle Scholar
[17]Jackson, F. H.The applications of basic numbers to Bessel's and Legendre's equations. Proc. Lond. Math. Soc. (2). 2 (1905), 192220.CrossRefGoogle Scholar
[18]Jackson, F. H.The basic gamma function and elliptic functions. Proc. Roy. Soc. A. 76 (1905), 127144.Google Scholar
[19]Jackson, F. H.On q-definite integrals. Quart. J. Pure and Appl. Math. 41 (1910), 193203.Google Scholar
[20]Katkova, O. M. and Vishnyakova, A. M.A sufficient condition for a polynomial to be stable. J. Math. Anal. Appl. 347 (2008), 8189.CrossRefGoogle Scholar
[21]Koelink, H. T. and Swarttouw, R. F.On the zeros of the Hahn–Exton q-Bessel function and associated q−Lommel polynomials. J. Math. Anal. Appl. 186 (1994), 690710.CrossRefGoogle Scholar
[22]Koornwinder, T. H. and Swarttouw, R. F.On a q−analog of Fourier and Hankel transforms. Trans. Amer. Math. Soc. 333 (1992), 445461.Google Scholar
[23]Kvitsinsky, A. A.Zeta functions, heat kernel expansions, and asymptotics for q-Bessel functions. J. Math. Anal. Appl. 196 (1995), 947964.CrossRefGoogle Scholar
[24]Levin, B. Ja.Distribution of Zeros of Entire Functions. Translations of Mathematical Monographs 5 (A.M.S. Providence, 1980).Google Scholar
[25]Pólya, G. and Szegő, G.Über die Nullstellen gewisser ganzer Funktionen. Math. Z. 2 (1918), 352383.CrossRefGoogle Scholar
[26]Pólya, G. and Szegő, G.Problems and Theorems in Analysis I. (Springer-Verlag, 1972).Google Scholar