bessel http://www.openmath.org/CDs/bessel.ocd 1/1/5000 private alg1 arith1 calculus1 fns1 relation1 This content dictionary contains symbols to describe the bessel functions and associated functions. BesselJ The BesselJ symbol represents the Bessel Functions of the first kind (of Integer Order). These are the solutions ,$J_{\pm \nu}(z)$, to the differential equation $z^2 \frac{d^2w}{dz^2}+z\frac{dw}{dz} + (z^2-\nu^2)w=0$ which has a branch cut along the negative real axis in the complex $z$ plane. When $\nu$ is integral they are analytic in the entire complex z plane. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [9.1.1] [9.1.20], [9.1.21] J : (integer, real) $\rightarrow$ real J : (integer, complex) $\rightarrow$ complex J : (symbolic, symbolic) $\rightarrow$ symbolic 2 $J_{\nu}(z)=\sum_{k=0}^{\infty} \frac{(-1)^k}{k!\Gamma(\nu+k+1)}(\frac{z}{2})^{\nu+2k}$, $|arg z| /lt \pi$, ascending series $J_n(z)=\frac{1}{\pi} \int_0^{\pi} cos(n \theta- zsin \theta) d \theta$, integral representation $J_{-n}(z)=(-1)^nJ_n(z)$, symmetry $J^{\prime}_0(z)=-J_1(z)$, derivative BesselY The symbol BesselY represents Bessel Functions of the second kind (of integer order). These are also known as Weber /functions. We denote these by $Y_{\nu}(z)$. $Y_{\nu}(z)$ are the second kind of Bessel functions. They are defined in terms of first kind of Bessel functions as $Y_{\nu}(z)=\frac{J_{\nu}(z)cos(\nu\pi)-J_{-\nu}(z)}{sin(\nu\pi)}$. which has a branch cut along the negative real axis in the complex $z$ plane. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [9.1.2] Y : (integer, real) $\rightarrow$ real Y : (integer, complex) $\rightarrow$ complex Y : (symbolic, symbolic) $\rightarrow$ symbolic $Y_{-n}(z)=(-1)^nY_n(z)$, symmetry $Y^{\prime}_0(z)=-Y_1(z)$, derivative HankelH1 The symbol HankelH1 represents the first variety of Bessel Functions of the third kind (also called the Hankel functions of the first kind). They are denoted as $H_{\nu}^{(1)}(z)$. They are defined by $H_{\nu}^{(1)}(z)=J_{\nu}(z)+iY_{\nu}(z)$. They have a branch cut along the negative real axis in the complex $z$ plane. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [9.1.3] Function H^(1) : (real, real) $\rightarrow$ real H^(1) : (complex, complex) $\rightarrow$ complex H^(1) : (symbolic, symbolic) $\rightarrow$ symbolic $H_{-\nu}^{(1)}(z)=e^{\nu \pi i} H_{\nu}^{(1)}(z)$ H^{(1)}_\nu(z)=J_\nu(z)+iY_\nu(z) HankelH2 The symbol HankelH2 represents the second variety of Bessel Functions of the third kind (also called the Hankel functions of the second kind). They are denoted as $H_{\nu}^{(2)}(z)$. They are defined by $H_{\nu}^{(1)}(z)=J_{\nu}(z)-iY_{\nu}(z)$. They have a branch cut along the negative real axis in the complex $z$ plane. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [9.1.4] H^(2) : (real, real) $\rightarrow$ real H^(2) : (complex, complex) $\rightarrow$ complex H^(2) : (symbolic, symbolic) $\rightarrow$ symbolic $H_{-\nu}^{(2)}(z)=e^{-\nu \pi i} H_{\nu}^{(2)}(z)$ H^{(2)}_\nu(z)=J_\nu(z)-iY_\nu(z) BesselI The symbol BesselI represents the Modified Bessel Functions of the first kind. They are denoted by $I_{\pm\nu}(z)$. The $I_{\pm\nu}(z)$ are the solutions of the differential equation $z^2\frac{d^2w}{d^2z}+z\frac{dw}{dz}-(z^2+\nu^2)w=0$ which has a branch cut along the negative real axis in the complex $z$ plane. When $\nu$ is integral, $I_{\nu}$ is an entire function of z. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [9.6.1] Function I : (integer, real) $\rightarrow$ real I : (integer, complex) $\rightarrow$ complex I : (symbolic, symbolic) $\rightarrow$ symbolic $I_{\nu}(z)=\sum_{k=0}^{\infty} \frac{1}{k!\Gamma(\nu+k+1)} (\frac{z}{2})^{2k+\nu}$, ascending series $I_{-n}(z)=I_n(z)$ BesselK The symbol BesselK represents the Modified Bessel Functions of the second kind. They are denoted by $K_{\nu}(z)$. They are the solutions of the differential equation $z^2\frac{d^2w}{d^2z}+z\frac{dw}{dz}-(z^2+\nu^2)w=0$ which has a branch cut along the negative real axis in the complex $z$ plane. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [9.6.1] Function K : (integer, real) $\rightarrow$ real K : (integer, complex) $\rightarrow$ complex K : (symbolic, symbolic) $\rightarrow$ symbolic $K_{\nu}(z)=\frac{1}{2}\pi \frac{I_{-\nu}(z)-I_{\nu}(z)} {sin(\nu\pi)}$, relation to $I_{\nu}(z)$ $\sqrt{\frac{\pi}{2z}}K_{n+\frac{1}{2}}(z)= \frac{1}{2}\pi(-1)^{n+1} \sqrt{\frac{\pi}{2z}} [I_{n+\frac{1}{2}}(z) -I_{-n-\frac{1}{2}}(z)]$, relation to $I_{\nu}(z)$ $K_{-\nu}(z)=K_{\nu}(z)$ SphericalBesselj The symbol SphericalBesselj represents the Spherical Bessel Functions of the first kind. They are denoted by $j_{n}(z)$. They satisfy the differential equation $z^2 w^{\prime\prime}+2zw^{\prime}+[z^2-n(n+1)]w=0$. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [10.1.1] j : (integer, real) $\rightarrow$ real j : (integer, complex) $\rightarrow$ complex j : (symbolic, symbolic) $\rightarrow$ symbolic $j_{n}(z)=\sqrt{\frac{1}{2}\pi/z}J_{n+\frac{1}{2}}(z)$ SphericalBessely The symbol SphericalBessely represents the Spherical Bessel Functions of the second kind. They are denoted by $y_{n}(z)$. They satisfy the differential equation $z^2 w^{\prime\prime}+2zw^{\prime}+[z^2-n(n+1)]w=0$. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [10.1.1] Function y : (integer, real) $\rightarrow$ real y : (integer, complex) $\rightarrow$ complex y : (symbolic, symbolic) $\rightarrow$ symbolic $y_{n}(z)=\sqrt{\frac{1}{2}\pi/z}Y_{n+\frac{1}{2}}(z)$ SphericalHankel1 The symbol SphericalHankel1 represents the Spherical Hankel Functions of the first kind (also called the first variety of the spherical Bessel functions of the third kind). They are denoted by $h_{n}^{(1)}(z)$. They satisfy the differential equation $z^2 w^{\prime\prime}+2zw^{\prime}+[z^2-n(n+1)]w=0$. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [10.1.1] Function h^(1) : (integer, real) $\rightarrow$ real h^(1) : (integer, complex) $\rightarrow$ complex h^(1) : (symbolic, symbolic) $\rightarrow$ symbolic $h_{n}^{(1)}(z)=\sqrt{\frac{1}{2}\pi/z}H_{n+\frac{1}{2}}^{(1)}(z)$ SphericalHankel2 The symbol SphericalHankel2 represents the Spherical Hankel Functions of the second kind (also called the second variety of the spherical Bessel functions of the third kind). They are denoted by $h_{n}^{(2)}(z)$. They satisfy the differential equation $z^2 w^{\prime\prime}+2zw^{\prime}+[z^2-n(n+1)]w=0$. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [10.1.1] h^(2) : (integer, real) $\rightarrow$ real h^(2) : (integer, complex) $\rightarrow$ complex h^(2) : (symbolic, symbolic) $\rightarrow$ symbolic $h_{n}^{(2)}(z)=\sqrt{\frac{1}{2}\pi/z}H_{n+\frac{1}{2}} ^{(2)}(z)$ SphericalBesselI_nPlusHalf The symbol SphericalBesselI_nPlusHalf represents the Modified Spherical Bessel Functions of the first kind. They are denoted by $I_{n+\frac{1}{2}}(z)$. They satisfy the differential equation $z^2 w^{\prime\prime}+2zw^{\prime}+[z^2+n(n+1)]w=0$ where $n \geq 0$. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [10.2.2] Function I_{n+1/2} : (integer, real) $\rightarrow$ real I_{n+1/2} : (integer, complex) $\rightarrow$ complex I_{n+1/2} : (symbolic, symbolic) $\rightarrow$ symbolic $\sqrt{\frac{1}{2} \pi/z} I_{n+\frac{1}{2}}(z)= e^{-n \pi i/2}j_n(ze^{\pi i/2})$, (-$\pi \lt argz \leq \pi/2$) SphericalBesselI_MinusnPlusHalf The symbol SphericalBesselI_MinusnPlusHalf represents the Modified Spherical Bessel Functions of the second kind. They are denoted by $I_{-n-\frac{1}{2}}(z)$. They satisfy the differential equation $z^2 w^{\prime\prime}+2zw^{\prime}+[z^2+n(n+1)]w=0$ where $n \geq 0$. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [10.2.3] I_{-n-1/2} : (integer, real) $\rightarrow$ real I_{-n-1/2} : (integer, complex) $\rightarrow$ complex I_{-n-1/2} : (symbolic, symbolic) $\rightarrow$ symbolic $\sqrt{\frac{1}{2} \pi/z} I_{-n-\frac{1}{2}}(z)= e^{3(n+1) \pi i/2}y_n(ze^{\pi i/2})$, (-$\pi \lt argz \leq \pi/2$) SphericalBesselK_nPlusHalf The symbol SphericalBesselK_nPlusHalf represent the Modified Spherical Bessel Functions of the third kind. They are denoted by $K_{n+\frac{1}{2}}(z)$. They satisfy the differential equation $z^2 w^{\prime\prime}+2zw^{\prime}+[z^2+n(n+1)]w=0$ where $n \geq 0$. They are defined as in M. Abramowitz and I. Stegun, Handbook of Mathematical Functions, [10.2.4] K_{n+1/2} : (integer, real) $\rightarrow$ real K_{n+1/2} : (integer, complex) $\rightarrow$ complex K_{n+1/2} : (symbolic, symbolic) $\rightarrow$ symbolic $\sqrt{\frac{1}{2} \pi/z} K_{n+\frac{1}{2}}(z)= \frac{1}{2} \pi (-1)^{n+1}\sqrt{\frac{1}{2} \pi/z}[I_{n+\frac{1}{2}} -I_{-n-\frac{1}{2}}]$