DIPAC2011 - List of Keywords (cryogenics)

Paper	Title	Other Keywords	Page
MOPD19	Button BPM Development for the European XFEL	simulation, vacuum, linac, cavity	83
	D. Lipka, B. Lorbeer, D. Nölle, M. Siemens, S. Vilcins DESY, Hamburg, Germany
	Button beam position monitors will be the main BPM type used to measure the electron beam position at the European XFEL. Two different kinds of buttons are necessary: one type will be installed in the acceleration modules of the cold linac and the other in the warm environment. The electro-magnetic design of the feedthrough for both types of buttons will be discussed. A comparison of the designed and measured RF properties will be presented. In addition to the usual RF properties, also the properties at cryogenic level will play a role. HOM power must not heat up the BPM feedthroughs, in order to keep the cryo load of an overall accelerator module low, and also to prevent damage due to large temperature gradients over the ceramics of the feedthrough. First measurements with beam at FLASH show good agreement of the measured signals with the expectation.

MOPD82	Installation for Measurements of Secondary Emission Yield and Electron Cloud Lifetime in Magnetic Field	electron, cathode, vacuum, simulation	236
	A.A. Krasnov, V.V. Anashin, V.K. Ovchar, V.V. Smaluk, D.P. Sukhanov BINP SB RAS, Novosibirsk, Russia
	An experimental setup for investigations of electron-surface interaction and electron cloud behavior is under commissioning at BINP. The proposed method provides direct measurements of secondary emission yield and electron clouds lifetime in the presence of strong magnetic field. In principle, the experiments can be performed at cryogenic temperatures. The experimental data will help to figure out the process of reflection of low energy electrons from a metal surface and can be useful for improvement of computer codes developed for simulation of electron clouds behavior in a cold beam pipe of particle accelerators. The structure and performance capabilities of the setup are described, first experimental results are presented.

TUPD20	Pre-amplifier Impedance Matching for Cryogenic BPMs	impedance, vacuum, synchrotron, quadrupole	347
	P. Kowina, M. Freimuth, K. Gütlich, W. Kaufmann, H. Rödl, J. Wießmann GSI, Darmstadt, Germany N. Sobel, F. Völklein Hochschule RheinMain, Wiesbaden, Germany
	Beam Position Monitors (BPMs) for the FAIR fast-ramped super conducting synchrotron SIS-100 will be installed inside the cryostats of quadrupole magnets. This contribution focuses on the coupling path between BPM electrodes and low noise amplifiers installed outside the cryostat. Matching transformers (MT) meet well the requirements of reflection free signal transfer through the relative long lines without loading the capacitive BPM by 50 Ohm. Different transformers based on toroidal cores made out of Vitroperm-500F nanocrystalline were tested. The form of windings and circuit geometry were optimized to improve linearity allow for resonance-free transmission over a required frequency range from 0.1 MHz to 80 MHz. The MTs have to be balanced pair wise within 0.1 dB and the geometry of windings has to be mechanically stabilized using e.g. epoxy resin. A choice of different epoxy types and their suitability for cryogenic operation was tested in liquid Nitrogen and liquid Helium.
	Poster TUPD20 [0.655 MB]

TUPD66	Sensor Optimizations for a Cryogenic Current Comparator	pick-up, ion, antiproton, storage-ring	458
	R. Geithner, W. Vodel HIJ, Jena, Germany R. Geithner, R. Neubert, P. Seidel FSU Jena, Jena, Germany P. Kowina, F. Kurian, M. Schwickert GSI, Darmstadt, Germany R. von Hahn MPI-K, Heidelberg, Germany
	We present a non-destructive superconducting monitoring system for charged particles beams. The system uses the Cryogenic Current Comparator (CCC) principle with a low temperature DC-SQUID. The Cryogenic Current Comparator has shown its capability in the Horizontal Bi-Cavity Test Facility at the Helmholtz-Zentrum Berlin under noisy conditions. In this test facility for superconducting cavities the CCC setup was able to detect dark currents in the nA range. The suitability of the Cryogenic Current Comparator as a beam monitor for the Facility of Antiproton and Ion Research at GSI Darmstadt as well as for the Cryogenic Storage Ring at MPI Heidelberg will be pointed out and discussed. Special attention will be given to the ferromagnetic core materials embedded in the pickup coil.

TUPD83	Photodiode Calibration using an Electrical Substitution Radiometer in the Hard X-ray Region	simulation, photon, alignment, radiation	500
	N.I. Bolibruch, R. Igarashi, J.M. Vogt CLS, Saskatoon, Saskatchewan, Canada
	Funding: Work supported by NSERC, NRC, CIHR, WEDC. An electrical substitution radiometer under development at the Canadian Light Source (CLS) has been used to calibrate a photodiode (AXUV100) from International Radiation Detectors Inc. within an energy range of 8 keV to 30 keV. These measurements were made using monochromatic X-rays on the Biomedical Imaging and Therapy bend magnet beam line and the Hard X-Ray Microanalysis beam line at the CLS. The results were then compared with silicon absorption calculations using data from the NIST mass absorption coefficient tables. Good agreement has been found between the diode calibration obtained from the radiometer and the theoretical calculation of the diode response.

WEOC02	News About the Cryogenic Current Comparator for Beam Diagnostics	ion, antiproton, pick-up, simulation	569
	W. Vodel HIJ, Jena, Germany R. Geithner, R. Neubert, P. Seidel FSU Jena, Jena, Germany K.K. Knaack, K. Wittenburg DESY, Hamburg, Germany A. Peters HIT, Heidelberg, Germany H. Reeg, M. Schwickert GSI, Darmstadt, Germany
	An absolute and exact measurement of the intensity of charged particle beams - extracted from an accelerator or circulating in a Storage Ring - is one of the major problems of beam diagnostics. Also the measurement of so-called dark currents, generated by superconductive RF accelerator cavities at high voltage gradients to characterize the quality of these components becomes more and more important for the commissioning of new accelerators (XFEL). The Cryogenic Current Comparator (CCC) based on high precision LTS SQUIDs is an excellent tool to solve these problems. This contribution gives an overview on the development of SQUID-based CCC for nuclear physics from the first successful demonstration of the performance at GSI Darmstadt through the recently tested CCC for the XFEL at DESY to the latest improved version for FAIR.
	Slides WEOC02 [2.596 MB]

Paper

Title

Other Keywords

Page

MOPD19

Button BPM Development for the European XFEL

simulation, vacuum, linac, cavity

83

D. Lipka, B. Lorbeer, D. Nölle, M. Siemens, S. Vilcins
DESY, Hamburg, Germany

Button beam position monitors will be the main BPM type used to measure the electron beam position at the European XFEL. Two different kinds of buttons are necessary: one type will be installed in the acceleration modules of the cold linac and the other in the warm environment. The electro-magnetic design of the feedthrough for both types of buttons will be discussed. A comparison of the designed and measured RF properties will be presented. In addition to the usual RF properties, also the properties at cryogenic level will play a role. HOM power must not heat up the BPM feedthroughs, in order to keep the cryo load of an overall accelerator module low, and also to prevent damage due to large temperature gradients over the ceramics of the feedthrough. First measurements with beam at FLASH show good agreement of the measured signals with the expectation.

MOPD82

Installation for Measurements of Secondary Emission Yield and Electron Cloud Lifetime in Magnetic Field

electron, cathode, vacuum, simulation

236

A.A. Krasnov, V.V. Anashin, V.K. Ovchar, V.V. Smaluk, D.P. Sukhanov
BINP SB RAS, Novosibirsk, Russia

An experimental setup for investigations of electron-surface interaction and electron cloud behavior is under commissioning at BINP. The proposed method provides direct measurements of secondary emission yield and electron clouds lifetime in the presence of strong magnetic field. In principle, the experiments can be performed at cryogenic temperatures. The experimental data will help to figure out the process of reflection of low energy electrons from a metal surface and can be useful for improvement of computer codes developed for simulation of electron clouds behavior in a cold beam pipe of particle accelerators. The structure and performance capabilities of the setup are described, first experimental results are presented.

TUPD20

Pre-amplifier Impedance Matching for Cryogenic BPMs

impedance, vacuum, synchrotron, quadrupole

347

P. Kowina, M. Freimuth, K. Gütlich, W. Kaufmann, H. Rödl, J. Wießmann
GSI, Darmstadt, Germany
N. Sobel, F. Völklein
Hochschule RheinMain, Wiesbaden, Germany

Beam Position Monitors (BPMs) for the FAIR fast-ramped super conducting synchrotron SIS-100 will be installed inside the cryostats of quadrupole magnets. This contribution focuses on the coupling path between BPM electrodes and low noise amplifiers installed outside the cryostat. Matching transformers (MT) meet well the requirements of reflection free signal transfer through the relative long lines without loading the capacitive BPM by 50 Ohm. Different transformers based on toroidal cores made out of Vitroperm-500F nanocrystalline were tested. The form of windings and circuit geometry were optimized to improve linearity allow for resonance-free transmission over a required frequency range from 0.1 MHz to 80 MHz. The MTs have to be balanced pair wise within 0.1 dB and the geometry of windings has to be mechanically stabilized using e.g. epoxy resin. A choice of different epoxy types and their suitability for cryogenic operation was tested in liquid Nitrogen and liquid Helium.

Poster TUPD20 [0.655 MB]

TUPD66

Sensor Optimizations for a Cryogenic Current Comparator

pick-up, ion, antiproton, storage-ring

458

R. Geithner, W. Vodel
HIJ, Jena, Germany
R. Geithner, R. Neubert, P. Seidel
FSU Jena, Jena, Germany
P. Kowina, F. Kurian, M. Schwickert
GSI, Darmstadt, Germany
R. von Hahn
MPI-K, Heidelberg, Germany

We present a non-destructive superconducting monitoring system for charged particles beams. The system uses the Cryogenic Current Comparator (CCC) principle with a low temperature DC-SQUID. The Cryogenic Current Comparator has shown its capability in the Horizontal Bi-Cavity Test Facility at the Helmholtz-Zentrum Berlin under noisy conditions. In this test facility for superconducting cavities the CCC setup was able to detect dark currents in the nA range. The suitability of the Cryogenic Current Comparator as a beam monitor for the Facility of Antiproton and Ion Research at GSI Darmstadt as well as for the Cryogenic Storage Ring at MPI Heidelberg will be pointed out and discussed. Special attention will be given to the ferromagnetic core materials embedded in the pickup coil.

TUPD83

Photodiode Calibration using an Electrical Substitution Radiometer in the Hard X-ray Region

simulation, photon, alignment, radiation

500

N.I. Bolibruch, R. Igarashi, J.M. Vogt
CLS, Saskatoon, Saskatchewan, Canada

Funding: Work supported by NSERC, NRC, CIHR, WEDC.
An electrical substitution radiometer under development at the Canadian Light Source (CLS) has been used to calibrate a photodiode (AXUV100) from International Radiation Detectors Inc. within an energy range of 8 keV to 30 keV. These measurements were made using monochromatic X-rays on the Biomedical Imaging and Therapy bend magnet beam line and the Hard X-Ray Microanalysis beam line at the CLS. The results were then compared with silicon absorption calculations using data from the NIST mass absorption coefficient tables. Good agreement has been found between the diode calibration obtained from the radiometer and the theoretical calculation of the diode response.

WEOC02

News About the Cryogenic Current Comparator for Beam Diagnostics

ion, antiproton, pick-up, simulation

569

W. Vodel
HIJ, Jena, Germany
R. Geithner, R. Neubert, P. Seidel
FSU Jena, Jena, Germany
K.K. Knaack, K. Wittenburg
DESY, Hamburg, Germany
A. Peters
HIT, Heidelberg, Germany
H. Reeg, M. Schwickert
GSI, Darmstadt, Germany

An absolute and exact measurement of the intensity of charged particle beams - extracted from an accelerator or circulating in a Storage Ring - is one of the major problems of beam diagnostics. Also the measurement of so-called dark currents, generated by superconductive RF accelerator cavities at high voltage gradients to characterize the quality of these components becomes more and more important for the commissioning of new accelerators (XFEL). The Cryogenic Current Comparator (CCC) based on high precision LTS SQUIDs is an excellent tool to solve these problems. This contribution gives an overview on the development of SQUID-based CCC for nuclear physics from the first successful demonstration of the performance at GSI Darmstadt through the recently tested CCC for the XFEL at DESY to the latest improved version for FAIR.

Slides WEOC02 [2.596 MB]