IPAC2011 - List of Authors (Hofmann, A.)

Paper	Title	Page
TUPC085	Observation of Microwave Radiation using Low-cost Detectors at the ANKA Storage Ring	1203
	V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller, M.J. Nasse, N.J. Smale KIT, Karlsruhe, Germany F. Caspers CERN, Geneva, Switzerland P. Peier PSI, Villigen, Switzerland
	Funding: Work supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320 Synchrotron light sources emit Coherent Synchrotron Radiation (CSR) for wavelengths longer than or equal to the bunch length. At most storage rings CSR cannot be observed because the waveguide cuts off radiation with long wavelengths. There are different approaches for shifting the CSR to shorter wavelengths that can propagate through the beam pipe, e.g.: The accelerator optics can be optimized for a low momentum compaction factor, thus reducing the bunch length. Alternatively, laser slicing can modulate substructures on long bunches. Both techniques extend the CSR spectrum to shorter wavelengths, so that CSR is emitted at wavelengths above the waveguide cut off. Usually fast detectors, like superconducting bolometer detector systems or Schottky barrier diodes, are used for observation of dynamic processes in accelerator physics. In this paper, we present observations of microwave radiation at ANKA using an alternative detector, a LNB (Low Noise Block) system. These devices are usually used in standard TV-SAT-receivers and are very cheap. We determined the time response of LNBs to be below 100 ns. The sensitivity of LNBs is optimized to detect very low intensity "noise-like" signals.

TUPC087	Filling Pattern Measurements at the ANKA Storage Ring	1209
	B. Kehrer, N. Hiller, A. Hofmann, E. Huttel, V. Judin, M. Klein, S. Marsching, A.-S. Müller, N.J. Smale KIT, Karlsruhe, Germany
	For many accelerator physics studies, e.g. the investigation of coherent synchrotron radiation (CSR), a precise knowledge of the quantitative filling pattern (i.e. the number of electrons per bunch) is essential. This can be achieved by either using a linear detector (analog recording) or by employing the method of time-correlated single photon counting (TCSPC). At the ANKA storage ring both methods are in use. The analogue detection is based on the signal from a stripline or annular electrode, the TCSPC uses a Single Photon Avalanche Diode (SPAD). In this paper, we describe the experimental set-ups and present results of a comparison of the two techniques for single as well as for multi bunch filling patterns.

TUPC088	An Ionization Profile Monitor for the Determination of the FLASH and PITZ Beam Parameters	1212
	J. Mießner, H.-J. Grabosch, M. Markert, R. Sternberger DESY Zeuthen, Zeuthen, Germany A. Hofmann KIT, Karlsruhe, Germany K.I. Tiedtke DESY, Hamburg, Germany
	To operate FLASH (Free-electron LASer at Hamburg) successfully, accurate measurements of the photon beam parameters, like position and profile, are essential. The development of a specific Ionization Profile Monitor (IPM) is one contribution to the photon beam diagnostics, and currently one horizontal and one vertical oriented IPM are installed at FLASH. The working principle of the IPM is based on the detection of ions generated by interactions of the photon beam with the residual gas, which is always present in the beam line. An essential advantage of this method is that the beam is not influenced by the IPM, so it is possible to analyze the beam parameters without beam destruction. Moreover, the monitor is able to determine the relative position and the spatial profile of the beam with the precision of a few um. In this poster, the design and first measurements with the IPM taken at FLASH are presented. A good measuring accuracy of the IPM is obtained. Moreover, first results of measurements at PITZ (PhotoInjector Testfacility at Zeuthen) are given for one vertical oriented IPM with a up to 25 MeV electron beam.

THPC021	Status of Bunch Deformation and Lengthening Studies at the ANKA Storage Ring	2951
	N. Hiller, A. Hofmann, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller KIT, Karlsruhe, Germany
	Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320. At the ANKA storage ring (Karlsruhe, Germany) we use a Hamamatsu synchroscan streak camera to study the current dependent bunch lengthening and deformation effects . Previously the camera was used at an IR port, being available only occasionally. In October 2010, a dedicated “beam line” for the streak camera became operational. It is designed to have minimum dispersion and sufficient flux in the optical range at which the camera is most sensitive. This allows us to measure bunch profiles for a single bunch with a charge of less than 15 pC (40 μA), previously more than 55 pC were required to obtain a comparable signal. Along with the design and built-up, we present further measurements of bunch length and shape for different momentum compaction factors, RF voltages, beam energies and bunch charges to provide a complete bunch length map of the low alpha mode at ANKA.

Paper

Title

Page

Observation of Microwave Radiation using Low-cost Detectors at the ANKA Storage Ring

1203

V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller, M.J. Nasse, N.J. Smale
KIT, Karlsruhe, Germany
F. Caspers
CERN, Geneva, Switzerland
P. Peier
PSI, Villigen, Switzerland

Funding: Work supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320
Synchrotron light sources emit Coherent Synchrotron Radiation (CSR) for wavelengths longer than or equal to the bunch length. At most storage rings CSR cannot be observed because the waveguide cuts off radiation with long wavelengths. There are different approaches for shifting the CSR to shorter wavelengths that can propagate through the beam pipe, e.g.: The accelerator optics can be optimized for a low momentum compaction factor, thus reducing the bunch length. Alternatively, laser slicing can modulate substructures on long bunches. Both techniques extend the CSR spectrum to shorter wavelengths, so that CSR is emitted at wavelengths above the waveguide cut off. Usually fast detectors, like superconducting bolometer detector systems or Schottky barrier diodes, are used for observation of dynamic processes in accelerator physics. In this paper, we present observations of microwave radiation at ANKA using an alternative detector, a LNB (Low Noise Block) system. These devices are usually used in standard TV-SAT-receivers and are very cheap. We determined the time response of LNBs to be below 100 ns. The sensitivity of LNBs is optimized to detect very low intensity "noise-like" signals.

TUPC087

Filling Pattern Measurements at the ANKA Storage Ring

1209

B. Kehrer, N. Hiller, A. Hofmann, E. Huttel, V. Judin, M. Klein, S. Marsching, A.-S. Müller, N.J. Smale
KIT, Karlsruhe, Germany

For many accelerator physics studies, e.g. the investigation of coherent synchrotron radiation (CSR), a precise knowledge of the quantitative filling pattern (i.e. the number of electrons per bunch) is essential. This can be achieved by either using a linear detector (analog recording) or by employing the method of time-correlated single photon counting (TCSPC). At the ANKA storage ring both methods are in use. The analogue detection is based on the signal from a stripline or annular electrode, the TCSPC uses a Single Photon Avalanche Diode (SPAD). In this paper, we describe the experimental set-ups and present results of a comparison of the two techniques for single as well as for multi bunch filling patterns.

TUPC088

An Ionization Profile Monitor for the Determination of the FLASH and PITZ Beam Parameters

1212

J. Mießner, H.-J. Grabosch, M. Markert, R. Sternberger
DESY Zeuthen, Zeuthen, Germany
A. Hofmann
KIT, Karlsruhe, Germany
K.I. Tiedtke
DESY, Hamburg, Germany

To operate FLASH (Free-electron LASer at Hamburg) successfully, accurate measurements of the photon beam parameters, like position and profile, are essential. The development of a specific Ionization Profile Monitor (IPM) is one contribution to the photon beam diagnostics, and currently one horizontal and one vertical oriented IPM are installed at FLASH. The working principle of the IPM is based on the detection of ions generated by interactions of the photon beam with the residual gas, which is always present in the beam line. An essential advantage of this method is that the beam is not influenced by the IPM, so it is possible to analyze the beam parameters without beam destruction. Moreover, the monitor is able to determine the relative position and the spatial profile of the beam with the precision of a few um. In this poster, the design and first measurements with the IPM taken at FLASH are presented. A good measuring accuracy of the IPM is obtained. Moreover, first results of measurements at PITZ (PhotoInjector Testfacility at Zeuthen) are given for one vertical oriented IPM with a up to 25 MeV electron beam.

THPC021

Status of Bunch Deformation and Lengthening Studies at the ANKA Storage Ring

2951

N. Hiller, A. Hofmann, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller
KIT, Karlsruhe, Germany

Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320.
At the ANKA storage ring (Karlsruhe, Germany) we use a Hamamatsu synchroscan streak camera to study the current dependent bunch lengthening and deformation effects . Previously the camera was used at an IR port, being available only occasionally. In October 2010, a dedicated “beam line” for the streak camera became operational. It is designed to have minimum dispersion and sufficient flux in the optical range at which the camera is most sensitive. This allows us to measure bunch profiles for a single bunch with a charge of less than 15 pC (40 μA), previously more than 55 pC were required to obtain a comparable signal. Along with the design and built-up, we present further measurements of bunch length and shape for different momentum compaction factors, RF voltages, beam energies and bunch charges to provide a complete bunch length map of the low alpha mode at ANKA.