#### Research Articles

# Exact formula for the sum of the squares of the Bessel function and the Neumann function of the same order of half-odd integer

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**Authors:**

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RAD Piyadasa ,

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Department of Mathematics, University of Kelaniya, Kelaniya, LK

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DK Mallawa Arachchi

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Department of Mathematics, University of Kelaniya, Kelaniya, LK

## Abstract

Sum of the squares of the Bessel function and the Neumann function of the same order of half-odd integer has been found to be very useful in addressing a puzzle in nuclear physics. One approximate formula available in the literature is valid for the complex argument whose real part is greater than zero, and the absolute value of error term is undefined for half-odd integers. Another approximate formula which is valid for all complex arguments has been obtained using sophisticated mathematical method called Barnes' method. However, the error in the formula is very difficult to calculate. We have obtained exact formula for the sum of the squares of Bessel and Neumann functions of the same order of half-odd integers which is valid for all complex arguments, and its proof is also given.

**Keywords:** Bessel functions; Neumann functions; Anomalous absorption; Partial waves

DOI: 10.4038/josuk.v4i0.2694

*J Sci.Univ.Kelaniya *4 (2008): 15-20
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How to Cite:
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Piyadasa, R. and Arachchi, D.M., 2011. Exact formula for the sum of the squares of the Bessel function and the Neumann function of the same order of half-odd integer. *Journal of Science of the University of Kelaniya Sri Lanka*, 4, pp.15–20. DOI: http://doi.org/10.4038/josuk.v4i0.2694
Published on
17 Jan 2011.

Peer Reviewed

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