Mao, L. J.

Paper	Title	Page
MOIO01	Electron Cooling Performance at IMP Facility	1
	X. D. Yang, W. P. Chai, H. Jia, G. H. Li, J. Li, P. Li, X. M. Ma, L. J. Mao, R. S. Mao, M. T. Song, T. L. Yan, J. C. Yang, D. Y. Yin, Y. J. Yuan, W. Zhang, X. H. Zhang, T. C. Zhao, W. H. zheng IMP, Lanzhou
	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, the momentum spread of the ion beam varying with particle number was measured during the ion beam decay, 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.
	Slides
TUPS03	Closed Orbit Correction in 2 MeV Electron Cooler Section at COSY-Juelich	92
	L. J. Mao, J. Dietrich, V. Kamerdzhiev, B. Lorentz, H.-J. Stein FZJ, Jülich
	A 2 MeV magnetized electron cooling system will be installed in COSY to boost the luminosity for future high density internal target experiments. For an effective electron cooling, the proton beam and electron beam have to overlap coaxially, it lead to the necessity of a good orbit correction in cooler section. Since the toroid magnets, the proton beam orbit distortion is anti-symmetric in horizontal plane. With steerers at each side of cooler, the proton beam can be made coaxial in the cooler and the deflection can be compensated. The distortion caused by bending coils in toroid is symmetric in vertical plane. A four-bump method is suggested for correction. Using the magnetic field data measured in BINP, we calculated the orbit distortion of proton beam at injection energy, and investigated the scheme of closed orbit correction. The simulation of orbit distortion and result of the correction are presented in this paper.
TUPS05	Simulation of High-Energy Electron Cooling at COSY with BETACOOL Program	95
	L. J. Mao, J. Dietrich FZJ, Jülich
	A 2 MeV electron cooling device will be installed at COSY in order to boost the luminosity of pellet target experiments. The magnetized electron cooling technique is used to compensate the energy loss and emittance growth for future COSY pellet target experiments. In this article, a numerical simulation of cooling process is performed with BETACOOL code. The cooling time is calculated for variant cooler setting parameters. The intrabeam scattering (IBS) and target effect are essential for prediction of equilibrium beam parameters. The influence of the pellet target on the beam parameters is demonstrated.