Radius of α-Spirallikeness of Order cos(α)/2 for Entire Functions

We determine the radius of α-spirallikeness of order cos(α)/2 for entire functions represented as infinite products of their positive zeros. The discussion includes several examples featuring special functions such as Gamma functions, Bessel functions, Struve functions, Wright functions, Ramanujan-type entire functions, and q-Bessel functions. We also consider combinations of classical Bessel functions, including both first-order and second-order derivatives. Additionally, several other special functions that can be incorporated into the established classes are described. We utilize Mathematica 12 software to compute the numerical values of the radius for some functions.