FAIR next generation scientists - 8th Edition Workshop

Recently, the BESIII collaboration has produced new data for the $\mathrm{\Lambda }$ baryon electric and magnetic form factor's ratio $G_E^{\mathrm{\Lambda }}/G_M^{\mathrm{\Lambda }}$ in the time-like region with high accuracy. By assuming the analyticity of the baryon form factors, a dispersive procedure can be used to analyze the data under a set of theoretical constraints. The dispersive procedure allows to determine behaviour of the modulus and the phase of the form factor's ratio in the time-like and space-like regions. Different classes of solutions are taken into account, and the results shed new light on interesting properties, such as the presence of zeroes of the form factor’s ratio in the space-like region. The new data, alongside the ones previously obtained by the collaboration, are used to eliminate the uncertainty on the ratio's phase showing new aspects of the $\mathrm{\Lambda }$ form factors which were unaccessible until now.