title: New Sum Rule for the Nuclear Magnetic Polarizability.
abstract: The well-known Levinger-Bethe photonuclear sum rule relates the strength of the photoexcitation of the giant dipole resonance in a nucleus to the number of nucleons in that nucleus. I extend this sum rule to the case of virtual photons and relate the size of the magnetic polarizability of a nucleus to the Q^{2} slope of the transverse virtual photoabsorption cross section integrated over the energy in the nuclear range. I check this sum rule for the deuteron where necessary data is available, discuss possible applications and connection with other sum rules postulated in the literature.
authors.affiliation: PRISMA Cluster of Excellence, Institut für Kernphysik, Johannes Gutenberg-Universität, 55099 Mainz, Germany.
authors.forename: Mikhail
authors.initials: M
authors.lastname: Gorchtein