i've looked online and the closest i've found to a definition is this: what does this mean? i understand that an unstable baryon will decay into proton / neutron and a pion via the strong force. but what actually is this resonance? is it a resonance in the traditional sense? is it referring to the excited state of the baryon? does it have modes of vibration? if someone could shed a little light on this it would be appreciated as there appears to be very little information on the internet that explains what a baryon resonance actually is or to what property the term 'resonance' actually refers.