Performance of the single-pass monitor system at SOR-RING

Abstract

The outlines of a program to develop a single-pass beam position monitor using a fast digitizing oscilloscope as one of the researches for the VSX (Vacuum Soft X-ray) accelerator facility at SOR (Synchrotron Orbital Radiation)-RING were described. The design conditions of the single-pass monitoring were briefly presented in respect to such as high speed digitizing oscilloscope, BT (Beam Transport) line, cable attenuation, maximum record length, digitized data transmission, and time duration. For the beam position calculation, two methods of data processing, that is, the peak height method and the integration method, were adopted. As to the relative accuracy of beam positions, the measured accuracy for the integration method was shown in figures. The relative accuracy with standard deviation less than 0.1 mm has been obtained. The differences of relative accuracy between two methods have been examined. It was found that the relative accuracy became almost constant for the number of sampling data points more than 250, and that the integration method gave higher accuracy than the peak-height methods.

SOR(シンクロトロン軌道放射)-RINGのVSX(真空軟X線)加速装置に向けた研究の一端としての、高速デジタルオシロスコープを用いたシングルビーム位置モニタの開発プログラムの概要を記述した。シングルパスモニタの設計条件を、高速デジタル化オシロスコープ、BT(ビーム輸送)ライン、ケーブル減衰、最大レコード長、デジタルデータ伝送、持続時間などに関して簡単に述べた。ビーム位置計算については、2つのデータ処理法、すなわち、ピーク高さ法および積分法を採用した。ビーム位置の相対精度については、積分法による実測精度を図に示した。標準偏差が0.1mm以下の相対精度を達成した。2方法間の相対精度の差を検討した。標本データ点数が250以上になると相対精度はほぼ一定となること、積分法の方がピーク高さ法よりも精度が高いことが分かった。