IPAC2011 - Classification: 06 Beam Instrumentation and Feedback / T24 Timing and Synchronization

Paper	Title	Page
MOPO037	Concept of Femtosecond Timing and Synchronization Scheme at ELBE	565
	M. Kuntzsch, A. Büchner, M. Gensch, A. Jochmann, T. Kirschke, U. Lehnert, F. Röser HZDR, Dresden, Germany M.K. Bock, M. Bousonville, M. Felber, T. Lamb, H. Schlarb, S. Schulz DESY, Hamburg, Germany
	The Radiation Source ELBE at Helmholtz-Zentrum Dresden-Rossendorf is undergoing an extension to offer capacity for various applications. The extension includes the setup of a THz-beamline with a dedicated laboratory and a beamline for electron-beam - high-power laser interaction. The current synchronization scheme offers stability on the picoseconds level. For pump-probe experiments using optical lasers, the desired synchronization between the pump and the probe pulse should be on the femtosecond scale. In the future there will be an optical synchronization system with a pulsed fiber laser as an optical reference. The laser pulses will be distributed over stabilized fiber links to the remote stations. It is planned to install EOM-based beam arrival time monitors (BAMs) in order to monitor the bunch jitter and to establish a beam-based feedback to reduce the jitter. Besides that, the timing system has to be revised to generate triggers for experiments with low repetition rate, two electron guns (thermionic DC, superconducting RF) and several lasers. The Poster will show the possible layout of the future Timing and Synchronization System at ELBE.

MOPO039	B-train Performances at CNAO	568
	M. Pezzetta, G. Bazzano, E. Bressi, L. Falbo, C. Priano, M. Pullia CNAO Foundation, Milan, Italy O. Coiro, G. Franzini, D. Pellegrini, M. Serio, A. Stella INFN/LNF, Frascati (Roma), Italy G. Venchi University of Pavia, Pavia, Italy
	The commissioning of CNAO, the Italian Centre of Oncological Hadrontherapy, with proton beams is completed. The real-time measurement of the synchrotron dipole field with the so-called B-train, together with its electronic systems and related software and firmware are here described. An additional magnet, powered in series with the synchrotron dipoles, is equipped with a special coil that measures the field integral variation along the beam nominal path. The voltage induced in the coil is digitized with a fast ADC and numerically integrated by an FPGA. The field integral is then distributed to the users every time that the equivalent field changes by 0.1 G. The measured B field ranges from 0 to 1.6 T with maximum ramps of 3 T/s. The B-train system will be used to provide feedback in field to the dipole power supply. It will handle the limited bandwidth of the active filter, the B-field lag in the magnets and will avoid current jumps.

MOPO040	RF Reference Distribution for the Taiwan Photon Source	571
	K.H. Hu, Y.-T. Chang, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, S.Y. Hsu, C.H. Kuo, D. Lee, C.-Y. Liao, C.Y. Wu NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) is a low-emittance 3-GeV synchrotron light source with circumference of 518.4 m which is being under construction at National Synchrotron Radiation Research Center (NSRRC) campus. Low noise 500 MHz master oscillator and novel fiber based CW RF reference distribution system will be employed to take advantages of advanced technology in this field and deliver better performance. The preliminary test of the prototype system is summarized in this report.

MOPO041	Preliminary Testing of TPS Timing System	574
	C.Y. Wu, Y.-T. Chang, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-Y. Liao NSRRC, Hsinchu, Taiwan
	The timing system of Taiwan Photon Source (TPS) provides synchronization for electron gun, modulators of linac, pulse magnet power supplies, booster power supply ramp, bucket addressing of storage ring, diagnostic equipments, beamline gating signal for top-up injection. The timing system utilizes a central event generator to generate events and distribute them over optic fiber network, and decodes them at the event receivers. The system supports uplink functionality which will be used for the fast interlock system to distribute signals like beam dump and post-mortem trigger. The timing system has now been in operation for Linac of TPS. This paper presents prototype for the timing system of TPS.

Paper

Title

Page

Concept of Femtosecond Timing and Synchronization Scheme at ELBE

565

M. Kuntzsch, A. Büchner, M. Gensch, A. Jochmann, T. Kirschke, U. Lehnert, F. Röser
HZDR, Dresden, Germany
M.K. Bock, M. Bousonville, M. Felber, T. Lamb, H. Schlarb, S. Schulz
DESY, Hamburg, Germany

The Radiation Source ELBE at Helmholtz-Zentrum Dresden-Rossendorf is undergoing an extension to offer capacity for various applications. The extension includes the setup of a THz-beamline with a dedicated laboratory and a beamline for electron-beam - high-power laser interaction. The current synchronization scheme offers stability on the picoseconds level. For pump-probe experiments using optical lasers, the desired synchronization between the pump and the probe pulse should be on the femtosecond scale. In the future there will be an optical synchronization system with a pulsed fiber laser as an optical reference. The laser pulses will be distributed over stabilized fiber links to the remote stations. It is planned to install EOM-based beam arrival time monitors (BAMs) in order to monitor the bunch jitter and to establish a beam-based feedback to reduce the jitter. Besides that, the timing system has to be revised to generate triggers for experiments with low repetition rate, two electron guns (thermionic DC, superconducting RF) and several lasers. The Poster will show the possible layout of the future Timing and Synchronization System at ELBE.

MOPO039

B-train Performances at CNAO

568

M. Pezzetta, G. Bazzano, E. Bressi, L. Falbo, C. Priano, M. Pullia
CNAO Foundation, Milan, Italy
O. Coiro, G. Franzini, D. Pellegrini, M. Serio, A. Stella
INFN/LNF, Frascati (Roma), Italy
G. Venchi
University of Pavia, Pavia, Italy

The commissioning of CNAO, the Italian Centre of Oncological Hadrontherapy, with proton beams is completed. The real-time measurement of the synchrotron dipole field with the so-called B-train, together with its electronic systems and related software and firmware are here described. An additional magnet, powered in series with the synchrotron dipoles, is equipped with a special coil that measures the field integral variation along the beam nominal path. The voltage induced in the coil is digitized with a fast ADC and numerically integrated by an FPGA. The field integral is then distributed to the users every time that the equivalent field changes by 0.1 G. The measured B field ranges from 0 to 1.6 T with maximum ramps of 3 T/s. The B-train system will be used to provide feedback in field to the dipole power supply. It will handle the limited bandwidth of the active filter, the B-field lag in the magnets and will avoid current jumps.

MOPO040

RF Reference Distribution for the Taiwan Photon Source

571

K.H. Hu, Y.-T. Chang, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, S.Y. Hsu, C.H. Kuo, D. Lee, C.-Y. Liao, C.Y. Wu
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) is a low-emittance 3-GeV synchrotron light source with circumference of 518.4 m which is being under construction at National Synchrotron Radiation Research Center (NSRRC) campus. Low noise 500 MHz master oscillator and novel fiber based CW RF reference distribution system will be employed to take advantages of advanced technology in this field and deliver better performance. The preliminary test of the prototype system is summarized in this report.

MOPO041

Preliminary Testing of TPS Timing System

574

C.Y. Wu, Y.-T. Chang, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-Y. Liao
NSRRC, Hsinchu, Taiwan

The timing system of Taiwan Photon Source (TPS) provides synchronization for electron gun, modulators of linac, pulse magnet power supplies, booster power supply ramp, bucket addressing of storage ring, diagnostic equipments, beamline gating signal for top-up injection. The timing system utilizes a central event generator to generate events and distribute them over optic fiber network, and decodes them at the event receivers. The system supports uplink functionality which will be used for the fast interlock system to distribute signals like beam dump and post-mortem trigger. The timing system has now been in operation for Linac of TPS. This paper presents prototype for the timing system of TPS.