IPAC2019 - List of Authors (Chou, P.J.)

Paper	Title	Page
MOPGW093	Optics Calibration for Routine Operations In Taiwan Photon Source	335
	F.H. Tseng, C.H. Chen, P.J. Chou NSRRC, Hsinchu, Taiwan
	To ensure a stable performance of Taiwan Photon Source (TPS), we perform the calibration of accelerator optics using LOCO (Linear Optics from Closed Orbit) technique every month. After the optics and coupling corrections, the rms beta beatings in both planes are reduced to less than 1%. The emittance coupling ratio is also restored to within the design value.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPGW093
About •	paper received ※ 06 May 2019 paper accepted ※ 18 May 2019 issue date ※ 21 June 2019
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TUPMP041	Preliminary Design of RF-Shielded Bellows	1341
	Y.T. Huang, C.K. Chan, C.-C. Chang, C.M. Cheng, P.J. Chou, Y.C. Yang NSRRC, Hsinchu, Taiwan
	A new design of RF-shielded bellows is proposed for the TPS to alleviate wake field effects and Joule heating resulting from contact resistance at the contact interface of sliding two dissimilar metals. Most efforts are put into controlling corrosion which is regarded as the main cause of electrical contact degradation. Rh-Au is chosen as a mating interface because they are stable under high temperature condition. Experimental tests are made to find an effective plating thickness of Rh and Au and to determine a suitable normal load applicable on the Rh-Au interface. A preliminary design of RF-shielded bellows that can sustain thousands of cycles during their lifetime is under testing.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPMP041
About •	paper received ※ 06 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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TUPGW070	Multi-Bend Achromat Lattice Design for the Future of TPS Upgrade	1564
	M.-S. Chiu, P.J. Chou, J.C. Huang NSRRC, Hsinchu, Taiwan S.-Y. Lee Indiana University, Bloomington, Indiana, USA
	We present a TPS upgrade option with the hybrid 7BA (H7BA) lattice. We also derive a simple formula on optimal dipole angle distribution among H7BA dipoles. The agreement is satisfactory. We also report preliminary results on the dynamic aperture (DA) optimization. Possible improvement on H7BA lattice is outlined.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPGW070
About •	paper received ※ 24 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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TUPGW071	Optimization and Measurements on the Double Mini-Betay Lattice in the TPS Storage Ring	1567
	M.-S. Chiu, B.Y. Chen, C.H. Chen, J.Y. Chen, Y.-S. Cheng, P.C. Chiu, P.J. Chou, T.W. Hsu, K.H. Hu, J.C. Huang, P.Y. Huang, C.-C. Kuo, T.Y. Lee, C.Y. Liao, W.Y. Lin, Y.-C. Liu, H.-J. Tsai, F.H. Tseng NSRRC, Hsinchu, Taiwan
	The Taiwan Photon Source (TPS) is capable of operat-ing in multi-bunch and single-bunch mode. To operate in a hybrid mode as requested by users, we developed a lattice with chromaticities of 0.8/2 (x/y) to provide higher single bunch currents. Beam dynamics simulations and lattice characterizations including dynamic aperture, frequency map analysis, tune shift with energy, tune shift with amplitude, and betatron coupling will be discussed in this report.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPGW071
About •	paper received ※ 30 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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WEPTS053	Frequency Map Measurements at the TPS	3240
	C.H. Chen, B.Y. Chen, J.Y. Chen, M.-S. Chiu, P.J. Chou, T.W. Hsu, B.Y. Huang, C.-C. Kuo, W.Y. Lin, Y.-C. Liu, H.-J. Tsai, F.H. Tseng NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) has been operated for several years since it’s first light in December 2014. TPS has achieved reliable routine operation at 500 mA with more than 10 hrs beam lifetime. The dynamic aperture measurements and associated Frequency Map Analyses (FMA) at TPS reveal the beam dynamics behavior with and without insertion devices. A preliminary measurement study by using the turn-by-turn BPMs and comparison with the model simulation results will be presented in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPTS053
About •	paper received ※ 30 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019
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THPRB092	Reduction of Beam Induced RF-Heating in the Horizontal Stripline Kicker at the TPS	4035
	P.J. Chou, C.K. Chan, C.-C. Chang, K.T. Hsu, K.H. Hu, C.K. Kuan, I.C. Sheng NSRRC, Hsinchu, Taiwan
	In preparation for 500 mA operation at the Taiwan Pho-ton Source (TPS), we redesigned the horizontal stripline kicker for the beam feedback system to gain a smaller loss factor with higher shunt impedance. We introduced ground fenders (see Fig. 1) to this new design which resulted in the reduction of the loss factor and substantial increase of the kicker shunt impedance. The transverse profile of the kicker electrodes was matched to the race-track beam pipe in the straight sections to minimize broadband impedance. The ground fenders can reduce the leakage of image currents through the gaps between the two strip line electrodes and also help to achieve a better impedance matching for the TEM modes in the transmission lines formed by the stripline electrodes and beam pipe in the kicker. The RF design and analysis of trapped resonant modes in the kicker were simulated by the 3-D electromagnetic code GdfidL [1]. Results of the RF design and analysis of trapped resonant modes will be discussed together with analytical estimates of coupled bunch instabilities at a beam current of 500 mA.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB092
About •	paper received ※ 17 April 2019 paper accepted ※ 19 May 2019 issue date ※ 21 June 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Optics Calibration for Routine Operations In Taiwan Photon Source

335

F.H. Tseng, C.H. Chen, P.J. Chou
NSRRC, Hsinchu, Taiwan

To ensure a stable performance of Taiwan Photon Source (TPS), we perform the calibration of accelerator optics using LOCO (Linear Optics from Closed Orbit) technique every month. After the optics and coupling corrections, the rms beta beatings in both planes are reduced to less than 1%. The emittance coupling ratio is also restored to within the design value.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-MOPGW093

About •

paper received ※ 06 May 2019 paper accepted ※ 18 May 2019 issue date ※ 21 June 2019

Export •

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

TUPMP041

Preliminary Design of RF-Shielded Bellows

1341

Y.T. Huang, C.K. Chan, C.-C. Chang, C.M. Cheng, P.J. Chou, Y.C. Yang
NSRRC, Hsinchu, Taiwan

A new design of RF-shielded bellows is proposed for the TPS to alleviate wake field effects and Joule heating resulting from contact resistance at the contact interface of sliding two dissimilar metals. Most efforts are put into controlling corrosion which is regarded as the main cause of electrical contact degradation. Rh-Au is chosen as a mating interface because they are stable under high temperature condition. Experimental tests are made to find an effective plating thickness of Rh and Au and to determine a suitable normal load applicable on the Rh-Au interface. A preliminary design of RF-shielded bellows that can sustain thousands of cycles during their lifetime is under testing.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPMP041

About •

paper received ※ 06 May 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

Export •

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

TUPGW070

Multi-Bend Achromat Lattice Design for the Future of TPS Upgrade

1564

M.-S. Chiu, P.J. Chou, J.C. Huang
NSRRC, Hsinchu, Taiwan
S.-Y. Lee
Indiana University, Bloomington, Indiana, USA

We present a TPS upgrade option with the hybrid 7BA (H7BA) lattice. We also derive a simple formula on optimal dipole angle distribution among H7BA dipoles. The agreement is satisfactory. We also report preliminary results on the dynamic aperture (DA) optimization. Possible improvement on H7BA lattice is outlined.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPGW070

About •

paper received ※ 24 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

Export •

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

TUPGW071

Optimization and Measurements on the Double Mini-Betay Lattice in the TPS Storage Ring

1567

M.-S. Chiu, B.Y. Chen, C.H. Chen, J.Y. Chen, Y.-S. Cheng, P.C. Chiu, P.J. Chou, T.W. Hsu, K.H. Hu, J.C. Huang, P.Y. Huang, C.-C. Kuo, T.Y. Lee, C.Y. Liao, W.Y. Lin, Y.-C. Liu, H.-J. Tsai, F.H. Tseng
NSRRC, Hsinchu, Taiwan

The Taiwan Photon Source (TPS) is capable of operat-ing in multi-bunch and single-bunch mode. To operate in a hybrid mode as requested by users, we developed a lattice with chromaticities of 0.8/2 (x/y) to provide higher single bunch currents. Beam dynamics simulations and lattice characterizations including dynamic aperture, frequency map analysis, tune shift with energy, tune shift with amplitude, and betatron coupling will be discussed in this report.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-TUPGW071

About •

paper received ※ 30 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

Export •

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

WEPTS053

Frequency Map Measurements at the TPS

3240

C.H. Chen, B.Y. Chen, J.Y. Chen, M.-S. Chiu, P.J. Chou, T.W. Hsu, B.Y. Huang, C.-C. Kuo, W.Y. Lin, Y.-C. Liu, H.-J. Tsai, F.H. Tseng
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) has been operated for several years since it’s first light in December 2014. TPS has achieved reliable routine operation at 500 mA with more than 10 hrs beam lifetime. The dynamic aperture measurements and associated Frequency Map Analyses (FMA) at TPS reveal the beam dynamics behavior with and without insertion devices. A preliminary measurement study by using the turn-by-turn BPMs and comparison with the model simulation results will be presented in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-WEPTS053

About •

paper received ※ 30 April 2019 paper accepted ※ 22 May 2019 issue date ※ 21 June 2019

Export •

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

THPRB092

Reduction of Beam Induced RF-Heating in the Horizontal Stripline Kicker at the TPS

4035

P.J. Chou, C.K. Chan, C.-C. Chang, K.T. Hsu, K.H. Hu, C.K. Kuan, I.C. Sheng
NSRRC, Hsinchu, Taiwan

In preparation for 500 mA operation at the Taiwan Pho-ton Source (TPS), we redesigned the horizontal stripline kicker for the beam feedback system to gain a smaller loss factor with higher shunt impedance. We introduced ground fenders (see Fig. 1) to this new design which resulted in the reduction of the loss factor and substantial increase of the kicker shunt impedance. The transverse profile of the kicker electrodes was matched to the race-track beam pipe in the straight sections to minimize broadband impedance. The ground fenders can reduce the leakage of image currents through the gaps between the two strip line electrodes and also help to achieve a better impedance matching for the TEM modes in the transmission lines formed by the stripline electrodes and beam pipe in the kicker. The RF design and analysis of trapped resonant modes in the kicker were simulated by the 3-D electromagnetic code GdfidL [1]. Results of the RF design and analysis of trapped resonant modes will be discussed together with analytical estimates of coupled bunch instabilities at a beam current of 500 mA.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2019-THPRB092

About •

paper received ※ 17 April 2019 paper accepted ※ 19 May 2019 issue date ※ 21 June 2019

Export •

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