Indian Journal of Cryogenics

In a Penning trap, charged particles reside in a dynamic confinement in 3D space by a time-independent homogeneous magnetic field and a quadrupolar electro-static potential, undergoing axial, cyclotron and magnetron harmonic motions. The precision measurements of the frequencies of these harmonic motions provide information on several fundamental properties of the trapped charged particles, such as mass, g-factor etc. However, such high precision measurements become possible only at ultra-low electronic noise conditions achievable at 4K. The present configuration of the VECC, Penning trap assembly comprises a 5-electrode cylindrical trap and two annular magnets providing a magnetic field of ~0.1T. The detection electronics comprising a helical resonator and a low noise cryogenic amplifier followed by the electronics to detect the weak beat signal were developed at VECC, Kolkata. The trap signal and its characteristics were observed and studied at 4K. The challenges in operating the Penning Trap at 4K are presented here.