Electron Cooling Performance at IMP Facility

TL;DR

This paper reports on the performance of electron cooling at the IMP facility, analyzing ion beam accumulation, lifetime, momentum spread, and beam oscillations under various electron beam profiles and conditions.

Contribution

It presents experimental results on electron cooling efficiency, beam lifetime, and momentum spread, along with upgrades to the cooling systems, advancing understanding of beam dynamics at IMP.

Findings

Maximum ion beam intensity achieved in 10 seconds.

Measured ion beam lifetime and momentum spread variations.

Observed oscillations and frequency shifts in the ion beam.

Abstract

The ion beam of 58Ni19+ with the energy of 6.39MeV/u was accumulated in the main ring of HIRFL-CSR with the help of electron cooling. The related angle between ion and electron beams in the horizontal and vertical planes was intentionally created by the steering coils in the cooling section after maximized the accumulated ion beam in the ring. The radial electron intensity distribution was changed by the ratio of potentials of grid electrode and anode of the electron gun, the different electron beam profiles were formed from solid to hollow in the experiments. In these conditions, the maximum accumulated ion beam intensity in the 10 seconds was measured, the lifetime of ion beam was measured, simultaneously the momentum spread of the ion beam varying with particle number was measured during the ion beam decay, furthermore, and the power coefficient was derived from these data. In additional, the momentum spread in the case of constant particle number was plotted with the angle and electron beam profile. The oscillation and shift of the central frequency of the ion beam were observed during the experiments. The upgrade and improvement in the CSRm cooler and the progress in the CSRe cooler were presented. These results were useful to attempt the crystal beam forming investigation in the CSR.