Magnetic excitation in relativistic heavy ion collisions

TL;DR

This paper investigates how strong magnetic fields in ultraperipheral relativistic heavy ion collisions can induce nucleon-to-delta transitions, leading to potential observable pion production.

Contribution

It introduces a model for magnetic field-induced nucleon-delta conversion and estimates the transition probability and cross section in heavy ion collisions.

Findings

Estimated transition probability for nucleon to delta conversion.

Calculated cross section for delta production.

Potential for experimental detection via forward pions.

Abstract

In this note we study the conversion of nucleons into deltas induced by a strong magnetic field in ultraperipheral relativistic heavy ion collisions. The interaction Hamiltonian couples the magnetic field to the spin operator, which, acting on the spin part of the wave function, converts a spin 1/2 into a spin 3/2 state. We estimate this transition probability and calculate the cross section for delta production. This process can in principle be measured, since the delta moves close to the beam and decays almost exclusively into pions. Forward pions may be detected by forward calorimeters.