A very informative video can be found here. Electron Spin Resonance (ESR) is also referred to as Electron Paramagenetic Resonance (EPR) is a direct method for measuring the absorption of microwave ...

They are thin glass walled tubes, uniformly thick, that produce low background noise. Electron spin resonance (ESR), also referred to as electron paramagnetic resonance (EPR), is a direct method for ...