FEL2015 - List of Keywords (klystron)

Paper	Title	Other Keywords	Page
MOP029	PAL XFEL Pulse Modulator System Test Results Using a High Precision CCPS	controls, power-supply, high-voltage, resonance	89
	S.H. Kim, H.-S. Kang, G.H. Kim, I.S. Ko, S.J. Kwon, H.-S. Lee, S.S. Park, Y.J. Park PAL, Pohang, Kyungbuk, Republic of Korea M.-H. Cho POSTECH, Pohang, Kyungbuk, Republic of Korea K.Y. Jang, H.S. Shin POSCO ICT, Gyeonggi-do, Republic of Korea D.S. Kim, S.Y. Lee, M. Seo Dawonsys, Siheung-City, Republic of Korea
	PAL XFEL is supposed to install 51 units of the pulse modulator power supplies for a 10-GeV linear accelerator using S-band (2856 MHz) cavities. The requirements of the modulator stability really become very tight. The stability on beam voltage is required to be less than 50 ppm. In order to obtain the high precision stability from the modulator system, we have newly produced a capacitor charging power supply (CCPS) and obtained the target stability with 10 ppm (STD) accuracy from measuring PFN (Pulse Forming Network). The CCPS generates a maximum output voltage of 50 kV at average current of 2.4 A with 4 units of the CCPS. The modulator peak output capacity is 400 kV, 500 A and 7.5 us at a pulse repetition rate of 60 pps using CCPS, a modified type-E PFN, and a pulse transformer. In this paper, the test results of the modulator system will be described.
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MOP039	First Results of Commissioning of the PITZ Transverse Deflecting Structure	electron, simulation, laser, emittance	110
	H. Huck, P. Boonpornprasert, A. Donat, J.D. Good, M. Groß, I.I. Isaev, L. Jachmann, D.K. Kalantaryan, M. Khojoyan, W. Köhler, G. Kourkafas, M. Krasilnikov, D. Malyutin, D. Melkumyan, A. Oppelt, M. Otevřel, M. Pohl, Y. Renier, T. Rublack, J. Schultze, F. Stephan, G. Trowitzsch, G. Vashchenko, R.W. Wenndorff, Q.T. Zhao DESY Zeuthen, Zeuthen, Germany G. Asova INRNE, Sofia, Bulgaria M. A. Bakr Assiut University, Assiut, Egypt D. Churanov, L.V. Kravchuk, V.V. Paramonov, I.V. Rybakov, A.A. Zavadtsev, D.A. Zavadtsev RAS/INR, Moscow, Russia C. Gerth, M. Hoffmann, M. Hüning DESY, Hamburg, Germany C. Hernandez-Garcia JLab, Newport News, Virginia, USA M.V. Lalayan, A.Yu. Smirnov, N.P. Sobenin MEPhI, Moscow, Russia O. Lishilin, G. Pathak Uni HH, Hamburg, Germany
	For successful operation of X-ray Free Electron Lasers, one crucial parameter is the ultrashort electron bunch length yielding a high peak current and a short saturation length. In order to effectively compress the bunches during the acceleration process, a detailed understanding of the full longitudinal phase space distribution already in the injector is required. Transverse deflecting RF structures (TDS) can shear the bunch transversely, mapping the longitudinal coordinate to a transverse axis on an observation screen downstream. In addition to the bunch length, the slice emittance along the bunch as well as the full longitudinal phase space can be obtained. At the Photo Injector Test Facility at DESY, Zeuthen site (PITZ), an S-band traveling wave TDS is under commissioning since 2015. This cavity is a prototype for the TDS in the injector part of the European XFEL and has been designed and manufactured by the Institute for Nuclear Research (INR, Moscow, Russia). In this paper, first commissioning results of the system at PITZ are presented and discussed.
	Poster MOP039 [0.893 MB]
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TUP010	Recent Progress in Upgrade of the High-Intensity THz-FEL at Osaka University	FEL, electron, linac, operation	354
	G. Isoyama, M. Fujimoto, S. Funakoshi, K. Furukawa, A. Irizawa, R. Kato, K. Kawase, A. Tokuchi, R. Tsutsumi, M. Yaguchi ISIR, Osaka, Japan
	We are upgrading the THz-FEL at Osaka University for its applications to high intensity THz sciences, which originally generated the high intensity FEL with the macropulse energy up to 3.7 mJ and the micropulse energy up to ~10 uJ at a wavelength around 70 um. To increase the micropulse energy, charge in electron bunches is increased four time higher and the bunch intervals are expanded four times longer to maintain the average current in the linac unchanged. In the new operation mode, the macropulse energy increases up to 26 mJ and the micropulse energy to ~0.2 mJ, which is 20 times higher than the energy previously obtained in the conventional mode. We have developed a solid-state switch for the klystron modulator to highly stabilize the klystron voltage, so that the output power of the FEL becomes stable. We are conducting basic studies on FEL for further improvement of its performance, including measurement of power evolution from start-up to saturation, time structures of FEL micropulses measured with a Michelson interferometer, and time structures of macropulses measured with a Schottky diode detector. We will report results of these studies on the THz-FEL at Osaka University.
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WEP037	Development Activites Related to RF Cables for Good Phase Stability	feedback, electron, network, controls	654
	J. Hu, H.-S. Kang, H.-S. Lee PAL, Pohang, Kyungbuk, Republic of Korea
	XFEL systems reqiure extreme RF stabilities in amplitude and phase. RF cables as parts of the systems also require very high stabilites. RF cable measurement is performed to choose good cables. Simple measurement method and test results are presented. To enhance the phase stability of RF cables a prototype jacket surrounding a RF cable is constructed and the test result is described. Finally, a modification for phase measurement of RF cables is presented.
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Paper

Title

Other Keywords

Page

MOP029

PAL XFEL Pulse Modulator System Test Results Using a High Precision CCPS

controls, power-supply, high-voltage, resonance

89

S.H. Kim, H.-S. Kang, G.H. Kim, I.S. Ko, S.J. Kwon, H.-S. Lee, S.S. Park, Y.J. Park
PAL, Pohang, Kyungbuk, Republic of Korea
M.-H. Cho
POSTECH, Pohang, Kyungbuk, Republic of Korea
K.Y. Jang, H.S. Shin
POSCO ICT, Gyeonggi-do, Republic of Korea
D.S. Kim, S.Y. Lee, M. Seo
Dawonsys, Siheung-City, Republic of Korea

PAL XFEL is supposed to install 51 units of the pulse modulator power supplies for a 10-GeV linear accelerator using S-band (2856 MHz) cavities. The requirements of the modulator stability really become very tight. The stability on beam voltage is required to be less than 50 ppm. In order to obtain the high precision stability from the modulator system, we have newly produced a capacitor charging power supply (CCPS) and obtained the target stability with 10 ppm (STD) accuracy from measuring PFN (Pulse Forming Network). The CCPS generates a maximum output voltage of 50 kV at average current of 2.4 A with 4 units of the CCPS. The modulator peak output capacity is 400 kV, 500 A and 7.5 us at a pulse repetition rate of 60 pps using CCPS, a modified type-E PFN, and a pulse transformer. In this paper, the test results of the modulator system will be described.

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reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

MOP039

First Results of Commissioning of the PITZ Transverse Deflecting Structure

electron, simulation, laser, emittance

110

H. Huck, P. Boonpornprasert, A. Donat, J.D. Good, M. Groß, I.I. Isaev, L. Jachmann, D.K. Kalantaryan, M. Khojoyan, W. Köhler, G. Kourkafas, M. Krasilnikov, D. Malyutin, D. Melkumyan, A. Oppelt, M. Otevřel, M. Pohl, Y. Renier, T. Rublack, J. Schultze, F. Stephan, G. Trowitzsch, G. Vashchenko, R.W. Wenndorff, Q.T. Zhao
DESY Zeuthen, Zeuthen, Germany
G. Asova
INRNE, Sofia, Bulgaria
M. A. Bakr
Assiut University, Assiut, Egypt
D. Churanov, L.V. Kravchuk, V.V. Paramonov, I.V. Rybakov, A.A. Zavadtsev, D.A. Zavadtsev
RAS/INR, Moscow, Russia
C. Gerth, M. Hoffmann, M. Hüning
DESY, Hamburg, Germany
C. Hernandez-Garcia
JLab, Newport News, Virginia, USA
M.V. Lalayan, A.Yu. Smirnov, N.P. Sobenin
MEPhI, Moscow, Russia
O. Lishilin, G. Pathak
Uni HH, Hamburg, Germany

For successful operation of X-ray Free Electron Lasers, one crucial parameter is the ultrashort electron bunch length yielding a high peak current and a short saturation length. In order to effectively compress the bunches during the acceleration process, a detailed understanding of the full longitudinal phase space distribution already in the injector is required. Transverse deflecting RF structures (TDS) can shear the bunch transversely, mapping the longitudinal coordinate to a transverse axis on an observation screen downstream. In addition to the bunch length, the slice emittance along the bunch as well as the full longitudinal phase space can be obtained. At the Photo Injector Test Facility at DESY, Zeuthen site (PITZ), an S-band traveling wave TDS is under commissioning since 2015. This cavity is a prototype for the TDS in the injector part of the European XFEL and has been designed and manufactured by the Institute for Nuclear Research (INR, Moscow, Russia). In this paper, first commissioning results of the system at PITZ are presented and discussed.

Poster MOP039 [0.893 MB]

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reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

TUP010

Recent Progress in Upgrade of the High-Intensity THz-FEL at Osaka University

FEL, electron, linac, operation

354

G. Isoyama, M. Fujimoto, S. Funakoshi, K. Furukawa, A. Irizawa, R. Kato, K. Kawase, A. Tokuchi, R. Tsutsumi, M. Yaguchi
ISIR, Osaka, Japan

We are upgrading the THz-FEL at Osaka University for its applications to high intensity THz sciences, which originally generated the high intensity FEL with the macropulse energy up to 3.7 mJ and the micropulse energy up to ~10 uJ at a wavelength around 70 um. To increase the micropulse energy, charge in electron bunches is increased four time higher and the bunch intervals are expanded four times longer to maintain the average current in the linac unchanged. In the new operation mode, the macropulse energy increases up to 26 mJ and the micropulse energy to ~0.2 mJ, which is 20 times higher than the energy previously obtained in the conventional mode. We have developed a solid-state switch for the klystron modulator to highly stabilize the klystron voltage, so that the output power of the FEL becomes stable. We are conducting basic studies on FEL for further improvement of its performance, including measurement of power evolution from start-up to saturation, time structures of FEL micropulses measured with a Michelson interferometer, and time structures of macropulses measured with a Schottky diode detector. We will report results of these studies on the THz-FEL at Osaka University.

Export •

reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)

WEP037

Development Activites Related to RF Cables for Good Phase Stability

feedback, electron, network, controls

654

J. Hu, H.-S. Kang, H.-S. Lee
PAL, Pohang, Kyungbuk, Republic of Korea

XFEL systems reqiure extreme RF stabilities in amplitude and phase. RF cables as parts of the systems also require very high stabilites. RF cable measurement is performed to choose good cables. Simple measurement method and test results are presented. To enhance the phase stability of RF cables a prototype jacket surrounding a RF cable is constructed and the test result is described. Finally, a modification for phase measurement of RF cables is presented.

Export •

reference for this paper to ※ LaTeX, ※ Text, ※ IS/RefMan, ※ EndNote (xml)