Beam based alignment of synchrotron under coupled quadrupole magnet environment

Hayashi, Naoki  ; Hatakeyama, Shuichiro; Harada, Hiroyuki  ; Hotchi, Hideaki  ; Takano, Jumpei*; Tejima, Masaki*; Toyama, Takeshi*

The Beam Based Alignment (BBA) of the BPM is inevitable for precise and absolute beam position measurements. Even though careful fabrication and installation of the BPM detector, it has to be calibrated by using the beam. Usually, it requires that the individual quadrupole magnet is able to be controlled. However, it is not always that case. In addition, scanning over the all BPM is time consuming procedure. The BBA method under coupled QM environment would help to reduce time for calibration. It presents general formula and experiences at J-PARC RCS and parts of results are compared with the ordinal method at J-PARC MR.