Questions tagged [bessel-functions]
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103
questions
7
votes
1answer
118 views
Reference for proof of an integral from the “Tables of Integral Transforms” involving a Gaussian and a Laguerre polynomial
I am looking for a proof of one of the integrals presented in Harry Bateman's Tables of Integral Transforms. The specific integral in question is presented on page 42 in chapter 8.9 as equation (3):
$$...
9
votes
1answer
365 views
An integral identity involving cotangents and Bessel functions
Numerical experiments suggest that the following integral identity holds for Bessel functions of the first kind,
$$J_2(t) = 12 \int_0^{1/2}\mathrm{d}x\,\cot \pi x \int_0^x \mathrm{d}y\, \cot \pi y \, ...
2
votes
2answers
45 views
Asymptotic behavior of a Bessel function on a sequence on zeros with a shifted parameter of type
Let $J_\nu$ be a Bessel function of the first kind and let $\{\lambda_{n, \nu}\}_{n\ge 1}$ be a sequence of its zeroes. I claim that
$$
\inf_{n\ge 1}\bigg|\sqrt{\lambda_{n,\nu}} J_{\nu+1}(\lambda_{n,\...
1
vote
0answers
96 views
A series with zeroes of Bessel functions
Consider a finite sum
$$
S_n(t)=\sum_{m=1}^n \frac{J_\nu(z_{m,\nu} t)}{J_{\nu+1}(z_{m,\nu})}, \nu>0, 0\leq t <1,
$$
$z_{m,\nu}$ are ordered real positive zeroes of the Bessel function $J_\nu(t)$....
0
votes
0answers
42 views
Can the Bessel functions tend to a plane wave?
Can the Bessel functions tend to a plane wave?
If I have this function:
$$
y(u)= c_1J_{-\sqrt{b}/2}(e^{2u}/6)+c_2J_{\sqrt{b}/2}(e^{2u}/6)+c_1J_{-i\sqrt{b}/2}(e^{2u}/6)+c_2J_{i\sqrt{b}/2}(e^{2u}/6)
$$
...
0
votes
0answers
126 views
A *natural* polynomial expansion of the Riemann $\xi(s)$ function
This is something that I've known for some time. Its an expansion of Riemann's $\xi$ function based on the traditional representation
$$
\xi(s)=\frac{1}{2}\left(1-s(1-s)\int_{1}^{\infty}\frac{\psi(x)}{...
0
votes
2answers
171 views
Orthogonality of Bessel function $\int_0^bxJ_a(\ell x)J_a(\ell' x)=0$ for $\ell\neq\ell'$
How do I show the above relation with Sturm-Liouville theory (assume the usual boundary conditions for the identity)? Here is what I have tried: if we start with
$$
\big(xJ_a'(\ell x)
\big)'+\left(\...
5
votes
2answers
176 views
Upper bounds for Bessel functions
Cosider the K-Bessel function $$K_\nu(x):= \frac\pi 2 \frac{I_{-\nu}(x)-I_\nu(x)}{\sin(\nu\pi)}.$$
See also Watson, G. N., A treatise on the theory of Bessel functions., Cambridge: University Press, ...
2
votes
2answers
140 views
Discrete random walk and SDEs
My advisor has some vague ideas about the relation between discrete random walks and SDEs, and advise me to read a little bit about them.
To be more precise, ( if I understand correctly what my ...
1
vote
0answers
104 views
What is the Jacobi-Anger expansion of $\sin^{[k]} (\theta) $?
Cross-post from MSE.
The Jacobi-Anger expansion gives expressions for functional iterates of trigonometric functions in terms of Bessel functions. For instance, we have $$\sin(z \sin(\theta)) = 2 \...
1
vote
0answers
51 views
Problem of correctly defining Hankel transforms
I have found the definition of the $v$-th order Hankel transform in the book of A.D. Poularikas "Transforms and applications" in Chapter $9$:
$$H_{v}(f(s))=\int_{0}^{+ \infty} rf(r) J_{v}(sr)...
2
votes
1answer
154 views
Definite integral of modified Bessel function of second kind
How do I integrate a modified Bessel function of the second kind as shown below? A good approximation of the definite integral is also ok, I do not need an exact solution.
$\int_\frac{1}{\lambda}^{\...
3
votes
0answers
80 views
Inverse mellin transform
Let $K_1(t)$ be the K-Bessel function, then we have
$\int_{0}^{\infty}K_v(y)y^s\frac{dy}{y}=2^{s-2}\Gamma(\frac{s+v}{2})\Gamma(\frac{s-v}{2})$ See page 106 of Bump's book Automorphic forms and ...
3
votes
0answers
126 views
L functions of Symmetric power of elliptic curves
Let $E$ be an elliptic curve over the raional field with conductor $N$, which corresponds to the eigenform $f(z)=\sum a_nq^n$. Let $L(Sym^2E,s)$ be the L function of the symmetric power of $E$.I am ...
3
votes
0answers
86 views
L functions of elliptic curves over quadratic fields
Let $E$ be an ellitpic curve over a quadratic field $K/\mathbb{Q}$. Then the L function of $E$ is defined as
$L(E_K,s)=\prod_{\mathfrak{p}\nmid \Delta}(1-a_{\mathfrak{p}}N(\mathfrak{p})^{-s}+N(\...
2
votes
1answer
131 views
Integral involving Bessel function
I have to work out the integral:
$$
\int_0^{\infty} dq \frac{J_0(q \xi)}{q+1}
$$
where $ J_0(z) $ is the Bessel function of the first type and order zero, $\xi \in \mathbb{R}$, $\xi \ge 0 $. So far, ...
0
votes
1answer
57 views
Variant of modified Bessel functions
Consider the integral
\begin{align*}
g_f(x)=\int_{\phi=0}^{2\pi} f(\phi) ~e^{x cos(\phi)}~\mathrm{d}\phi,
\end{align*}
where $f(\phi)$ is a probability density functions defined over $[0,2\pi]$,
\...
2
votes
1answer
81 views
Asymptotic behavior of maximum of bessel function
Let $J_n$ be the Bessel function of the first kind. Let $J_n^{(\max)} = \max_{x>0} J_n(x)$. What is known about the asymptotic behavior of $J_n^{(\max)}$ at large $n$? Specifically, I am looking ...
0
votes
0answers
52 views
Integral of an expression including a fraction having modified Bessel functions of the first kind on both numerator and denominator
I am looking for an analytic result of the following integral
$$\iint_0^\infty {{\rm{d}}x{\rm{d}}y{x^2}{y^2}\exp \left\{ { - {\alpha _1}{x^2} - {\alpha _2}{y^2}} \right\}\frac{{{\rm{I}}_1^2\left[ {\...
2
votes
1answer
249 views
Integral with 4 Bessel functions and an exponential
I would like to solve the following integral
$$
\int_0^\infty e^{-a k^2} J_{3/2}(b k) J_{3/2}(c k) J_{3/2}(f k) J_{1/2}(r k) k^{-3} dk,
$$
where $a,b,c,f,r > 0$, and $J_\nu(x)$ is the Bessel ...
3
votes
0answers
63 views
Limit of Hankel function for large complex order, fixed real argument
Consider the Hankel function $H_\nu(z)$ where $\nu=re^{i\theta}$ (real $z>0$, $r>0$, $0\leq\theta<\pi$) as $r\rightarrow\infty$. I am aware that the Bessel function $J_\nu(z)$ has the ...
3
votes
1answer
283 views
Almost periodicity of Bessel functions
We know that a periodic function (e.g. a trigonometric function) has the property
$$
f(x+n\Lambda)=f(x) \qquad n\in\mathbb Z
$$
A Bessel function is not exactly periodic, because the value of the ...
1
vote
1answer
212 views
A Bessel-like integral
I encounter the following integral when trying to find the inverse Fourier transform of the characteristic function of a certain sum of random variables. Here, $0\le\lambda\le1$, $p\ge0$, $q\ge0$ are ...
2
votes
1answer
289 views
Integral involving associated Laguerre polynomial and Bessel function
In a quantum mechanics problem I encountered the following integral
\begin{equation*}
\int_0^\infty t^{\nu+1}J_\nu(\beta t)L_{\mu-\nu}^{2\nu}(t)e^{-t/2}dt\,,
\end{equation*}
where $L$ denotes the ...
4
votes
1answer
99 views
Limit for series of Bessel functions evaluated at zeros
The following series arises in an electrostatics problem for a conducting cylinder:
$$
V=\sum_{n=1}^\infty\frac{J_0(k_n\rho)e^{-k_nz}}{k_nJ_1(k_n)^2}
$$
where $J_i$ is the Bessel function of $i^{th}$ ...
0
votes
1answer
382 views
Reciprocal expansion of modified Bessel function
I am reading Sherstyukov and Sumin - Reciprocal expansion of modified Bessel function in simple fractions and obtaining general summation relationships containing its zeros. The authors say they are ...
4
votes
1answer
314 views
Gegenbauer's addition theorem for Jacobi polynomials
I have the following identity,
$$\int_{-1}^{1} \! dz \, j_0\bigl(\sqrt{x^2 + y^2 - 2xy z}\bigr) \, P_n(z)
= 2 \, j_n(x) \, j_n(y) \;,$$
where $x, y > 0$, $P_n$ is a Legendre polynomial, and $...
0
votes
1answer
88 views
The ratio of Hankel functions
I have to obtain an asymptotic solution for small real positive $x$ for the ratio of Spherical Hankel functions ($n=0,1,2....)$
${h^{(2)}_n(x)}/{h^{(1)}_n(x)}$
I found that series should be
$-1 + i ...
2
votes
1answer
88 views
Can the integral $ \int_0^R\quad J_{m-n}(a r)J_m(b r) dr$ be explicitly represented in a closed form?
Doe the following definite integral have an explicit representation in terms of a Bessel functions or a generalized hypergeometric function ${}_pF_q$?
$$
\int_0^R\quad J_{m-n}(a r)J_m(b r) dr, \quad \...
0
votes
0answers
123 views
A complex integration formula
I'm trying to integrate a formula but I can’t figure it out. Its calculation involves an error function. Here's the formula:
$f(a, b, c)=\int_{0}^{+\pi} d \theta \exp (a \cos \theta) \operatorname{...
6
votes
3answers
298 views
A hypergeometric identity related to Bessel functions
The identity in my recent answer can be stated in a particularly neat form:
$${}_2F_0\left({-n, n+1\atop{}};\frac{x}{2}\right) ~\cdot~ {}_2F_0\left({-n, n+1\atop{}};-\frac{x}{2}\right) ~=~ {}_3F_0\...
6
votes
1answer
204 views
Spherical Bessel functions. Sum of squares
In (1) there is a property of spherical Bessel functions, which's derivation I can not find in the literature.
${\mathsf{j}_{n}^{2}}\left(z\right)+{\mathsf{y}_{n}^{2}}\left(z\right)=\sum_{k=%
0}^{n}\...
2
votes
1answer
137 views
How to compute means μ1 and μ2 knowing sum of Skellam distributions f(k;μ1,μ2) and sum μ1+μ2, where k is from 2 to n?
The probability mass function for the Skellam distribution for a count difference $ k=n_1-n_2 $ from two Poisson-distributed variables with means $\mu_1$ and $\mu_1$ is given by:
$$ f(k;\mu_1,\mu_2)=...
6
votes
0answers
139 views
Computing the difficult integral $\int_0^\infty J_0(x)^4\log(x)dx$
Computing numerically integrals of oscillating functions from $0$ to $\infty$ is a well-known and difficult problem. Here is an example for which I do not know a solution: I know how to compute (to ...
2
votes
1answer
139 views
How to get asymptotic expansion of the sum of modified Bessel function $\sum_{n=1}^\infty K_0(s\, n)$ as $s\to 0^+$?
I guess for the modified Bessel funcion $K_0(z)$,
$$\sum_{n=1}^\infty K_0(s\, n)
\sim
\frac{-2\log 2 - \log \pi + \gamma}{2} + \frac{\log s}{2} + \frac{\pi}{2\, s}, \quad s\to 0^+,$$
if taking
$$\...
0
votes
1answer
161 views
Alternate forms of the Bessel equation
I have a question regarding an alternate form of the Bessel equation and how that alternate form translates to the modified Bessel equation and its solution. The modified form is from:
http://...
0
votes
1answer
238 views
Closed form of integration of modified Bessel function composed with trigonometric function times a linear term
Assuming one draws two points from a von Mises distribution on a circle, I am looking for the expected distance between two such points.
Given the pdf of a centered von Mises distribution
$$f_X(t \...
4
votes
2answers
323 views
Asymptotics for the first zero of the Bessel functions
Let $J_\nu$ be the standard Bessel function of the first kind and let $x_\nu$ be its smallest zero. Is there a simple reference or result for the asymptotic expansion of $x_\nu$ when $\nu$ goes to $+\...
3
votes
3answers
421 views
Approximation of half-integers modified Bessel function of the second kind
I am trying to optimise the calculation of the probability distribution poisson-inverse-gaussian
its calculation involves a half-integers modified Bessel function of the second kind. Here's a formula ...
3
votes
3answers
235 views
ODE with Bessel decay
This is related to my previous question, but it is probably less scary and an expert in using Mathematica could figure out an answer easily.
I would like to estimate the asymptotic behaviour of the ...
2
votes
0answers
56 views
Bessel decay for nonhomogeneous PDE
I'm interested in the following nonhomogeneous PDE
$$ (\Delta-k^{2})u=-g $$
on the upper-half plane with smooth and integrable Dirichlet boundary condition, where $g$ is a smooth positive function ...
1
vote
0answers
95 views
Is the ratio of two distinct zeros of a Bessel function of the first kind an irrational number?
Let $J_1$ be the Bessel function of the first kind with parameter $\alpha=1$. Namely, $J_1$ satisfies the differential equation for $y$ given by $x^2y''+xy'+(x^2-1)y=0$ and $J_1(0)=0$.
Is it true ...
1
vote
0answers
58 views
Integral reducible to Bessel function
I wonder whether one could reduce the following integral to some combination of special (e.g. Bessel) functions: $$\int_{m}^{\infty}d\epsilon \exp\left(-s\epsilon\right)\left( \epsilon^{2}-m^{2}\right)...
9
votes
2answers
754 views
Kuznetsov trace formula, orthogonality of Bessel functions
Sorry if this is a vague question. I remember from my younger days that
before proving his trace formula, Kuznetsov had a pretty result on
orthogonality of Bessel functions. The formulas that I am ...
5
votes
2answers
427 views
An integral involving three Bessel functions
I am looking for a closed form for the following integral
$$ I = \int_0^\infty \mathrm{d} x \ x \ J_0(ax) J_0(bx) J_1(cx) $$
which can be thought of as a particular case of the more general integral
...
1
vote
0answers
188 views
Exponential decay of a convolution
Let $z=(x,y) \in \mathbb{R}^N \times (0,+\infty)$, and let
$$
P_m(z)=y^{2s} |z|^{-\frac{N+2s}{2}} K_{\frac{N+2s}{2}}(m|z|),
$$
where $N \geq 3$ is an integer, $0<s<1$ and $K_{\frac{N+2s}{2}}$ ...
0
votes
2answers
141 views
Literature about the integral of Bessel $\int_0^x I_{0,1}(u) e^{-a u}du$?
Thanks to sound remarks here and here, and looking again at these equations, I noticed that my puzzle boils down to these 2 special functions:
$$\int_0^x I_i(u) e^{-a u}du, \quad i=0,1$$
where $I_n(u)$...
2
votes
1answer
212 views
What can we know about “the half” of the generating series of Bessel function
I am interested in the series
$$\sum_{n\geq 1}I_n(x)\lambda^n$$
which is not the full generating series of the modified Bessel function of the first kind because it starts from $n=1$ and not at $-\...
7
votes
2answers
390 views
The tangent curve to Bessel functions?
Consider a function from the Bessel family, for concreteness say $f(x) := J_0(x)$, depicted in blue below (the question can be asked for any order of the first or second kind):
I'm interested in the ...
5
votes
1answer
639 views
Integral involving Laguerre, Gaussian and modified Bessel function
I am trying to prove that the integral
\begin{align}
\int_{0}^{\infty } e^{-\frac{r^2}{2B}} r^{l-n}
L_n^{l-n}\left(\frac{r^2}{C}\right) I_{l-n}\left(\rho r \right) r dr
\end{align}
has ...
