High intensity beam operation of J-PARC RCS with minimum beam loss

Saha, P. K.   ; Harada, Hiroyuki  ; Shobuda, Yoshihiro   ; Tamura, Fumihiko   ; Okita, Hidefumi  ; Okabe, Kota  ; Nakanoya, Takamitsu  ; Hatakeyama, Shuichiro; Moriya, Katsuhiro  ; Takayanagi, Tomohiro   ; Hotchi, Hideaki*

In this research, numerical simulation studies and beam tests were performed to minimize the beam loss at high intensity operation of J-PARC RCS. The beam loss usually increases non-linearly with respect to the beam power ramp up at high-intensity. The longitudinal and transverse injection painting used for space charge mitigation at a lower beam energy are optimized to produce a further uniform beam distribution to realize further space charge mitigation. The beam loss at the present operation at a net beam power of nearly 850 kW to the MLF has been kept to a minimum level to achieve a stable user operation. The beam loss at 1 MW beam power has also been sufficiently reduced to remain only 0.05% which is dominated by the unavoidable foil scattering beam loss.