検索対象:     
報告書番号:
※ 半角英数字
 年 ~ 
 年

Application of digital narrow band noise to J-PARC Main Ring

J-PARC Main Ringのための狭帯域ノイズ信号の応用

Schnase, A.; 田村 文彦   ; 小関 忠*; 冨澤 正人*; 外山 毅*; 吉井 正人*; 大森 千広*; 野村 昌弘  ; 山本 昌亘   ; 戸田 信*; 鈴木 寛光; 島田 太平 ; 原 圭吾*; 長谷川 豪志*

Schnase, A.; Tamura, Fumihiko; Koseki, Tadashi*; Tomizawa, Masahito*; Toyama, Takeshi*; Yoshii, Masahito*; Omori, Chihiro*; Nomura, Masahiro; Yamamoto, Masanobu; Toda, Makoto*; Suzuki, Hiromitsu; Shimada, Taihei; Hara, Keigo*; Hasegawa, Katsushi*

Applying narrow band noise to the beam in J-PARC Main Ring in flattop, while the acceleration voltage is off helps to counteract the effect of ripple on the slow extraction. For this purpose, a complex noise sequence output by DSP modulates a custom made DDS synthesizer to create single side spectra without carrier. The noise is calculated starting from a description in frequency domain. An algorithm creates narrow band spectra with optimized behavior in time domain. Frequency domain data is transformed to time domain, and the amplitude is smoothed. The smoothed data is transformed back to frequency domain, and the spectral shape is restored. This process repeats until the amplitude in time domain has converged, while the desired spectrum shape is preserved. Noise generated in this way can be tailored for different requirements. We show the signal properties, the hardware, and preliminary beam test results, when the noise is applied (a) to the MR RF system, and (b) to the horizontal exciter system.

Access

:

- Accesses

InCites™

:

Altmetrics

:

[CLARIVATE ANALYTICS], [WEB OF SCIENCE], [HIGHLY CITED PAPER & CUP LOGO] and [HOT PAPER & FIRE LOGO] are trademarks of Clarivate Analytics, and/or its affiliated company or companies, and used herein by permission and/or license.