IPAC2015 - List of Authors (Toyama, T.)

Paper	Title	Page
MOPHA058	Beam Based Gain Calibration for Beam Position Monitor at J-PARC Main Ring	927
	H. Kuboki, J. Takano, M. Tejima, T. Toyama KEK, Ibaraki, Japan S. Hatakeyama JAEA/J-PARC, Tokai-mura, Japan
	Funding: MEXT KAKENHI Grant Number 25105002, Grant-in-Aid for Scientific Research on Innovative Areas titled "Unification and Development of the Neutrino Science Frontier" Beam Position Monitor (BPM) is one of the essential elements in a synchrotron facility. It provides the accurate beam positions, which are used to correct the closed orbit distortion. Each BPM is installed with the electronics which enable to acquire the data of the turn-by-turn beam positions. Here, we define the "gain" as the proportionality coefficient between the signal detected at the ADC and the ideal signal without any errors. The signal strength from a BPM electrode varies depending on 1) transmission characteristics of a long cable, 2) processing circuit, and 3) contact resistance at the connected parts. These are the origin of the gain deviations. In order to correct the deviations, a Beam Based Gain Calibration (BBGC) method has been proposed . Development of a new method for adequate gain calibration is required because any calibration method for routine operation has not been established for BPMs with diagonal-cut electrodes used at J-PARC Main Ring. The results of analysis will be presented using the Total Least Square fitting as an adequate method for the BBGC with sufficient accuracy within 0.6% in one standard deviation. M. Tejima et al., DIPAC2011 (2011).
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA058
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MOPTY001	Development of Wideband BPM for Precise Measurement of Internal Bunch Motion	937
	K.G. Nakamura Kyoto University, Kyoto, Japan Y.H. Chin, T. Koseki, T. Obina, M. Okada, M. Tobiyama, T. Toyama KEK, Ibaraki, Japan Y. Shobuda JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	Funding: This work was supported by MEXT KAKENHI Grant Number 25105002, Grant-in-Aid for Scientific Research on Innovative Areas titled “ Unification and　Development of the Neutrino Science Frontier” To suppress intra-bunch oscillations and to reduce particle losses, the intra-bunch feedback (IBFB) system has been developed in 2014 for the J-PARC Main Ring (MR). A new BPM was also installed to the MR for the IBFB system. This BPM has a sufficient frequency response and position sensitivity(up to 1.5GHz within 15% fluctuation ). However, a better performance may be needed in future for more precise analysis of internal motions (e.g. due to an electron cloud). We report the development of the BPM and precise measurement results of the BPM characteristics. We also report simulation studies of the digital equalizer which helps to reconstructs the beam shape from beam signals.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPTY001
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Beam Based Gain Calibration for Beam Position Monitor at J-PARC Main Ring

927

H. Kuboki, J. Takano, M. Tejima, T. Toyama
KEK, Ibaraki, Japan
S. Hatakeyama
JAEA/J-PARC, Tokai-mura, Japan

Funding: MEXT KAKENHI Grant Number 25105002, Grant-in-Aid for Scientific Research on Innovative Areas titled "Unification and Development of the Neutrino Science Frontier"
Beam Position Monitor (BPM) is one of the essential elements in a synchrotron facility. It provides the accurate beam positions, which are used to correct the closed orbit distortion. Each BPM is installed with the electronics which enable to acquire the data of the turn-by-turn beam positions. Here, we define the "gain" as the proportionality coefficient between the signal detected at the ADC and the ideal signal without any errors. The signal strength from a BPM electrode varies depending on 1) transmission characteristics of a long cable, 2) processing circuit, and 3) contact resistance at the connected parts. These are the origin of the gain deviations. In order to correct the deviations, a Beam Based Gain Calibration (BBGC) method has been proposed *. Development of a new method for adequate gain calibration is required because any calibration method for routine operation has not been established for BPMs with diagonal-cut electrodes used at J-PARC Main Ring. The results of analysis will be presented using the Total Least Square fitting as an adequate method for the BBGC with sufficient accuracy within 0.6% in one standard deviation.
* M. Tejima et al., DIPAC2011 (2011).

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPHA058

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPTY001

Development of Wideband BPM for Precise Measurement of Internal Bunch Motion

937

K.G. Nakamura
Kyoto University, Kyoto, Japan
Y.H. Chin, T. Koseki, T. Obina, M. Okada, M. Tobiyama, T. Toyama
KEK, Ibaraki, Japan
Y. Shobuda
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

Funding: This work was supported by MEXT KAKENHI Grant Number 25105002, Grant-in-Aid for Scientific Research on Innovative Areas titled “ Unification and　Development of the Neutrino Science Frontier”
To suppress intra-bunch oscillations and to reduce particle losses, the intra-bunch feedback (IBFB) system has been developed in 2014 for the J-PARC Main Ring (MR). A new BPM was also installed to the MR for the IBFB system. This BPM has a sufficient frequency response and position sensitivity(up to 1.5GHz within 15% fluctuation ). However, a better performance may be needed in future for more precise analysis of internal motions (e.g. due to an electron cloud). We report the development of the BPM and precise measurement results of the BPM characteristics. We also report simulation studies of the digital equalizer which helps to reconstructs the beam shape from beam signals.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-MOPTY001

Export •

reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)