title: M(2) factor of Bessel Gauss beams.
abstract: We derive the analytical expression of the M(2) factor of a Bessel-Gauss beam of any order and discuss its behavior for high and low values of the width of the Gaussian profile. The case of unapertured Bessel beams can be treated as a limiting case of our analysis.
authors.forename: R
authors.initials: R
authors.lastname: Borghi
authors.forename: M
authors.initials: M
authors.lastname: Santarsiero