Radon transform. In $\mathbb {R}^ 3$ it maps a function to its surface integrals over circular
cones, and in $\mathbb {R}^ 2$ it maps a function to its integrals along two rays with a
common vertex. Such transforms appear in various mathematical models arising in medical
imaging, nuclear industry and homeland security. This paper contains new results about
inversion of conical Radon transform with fixed opening angle and vertical central axis in …