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Klein, M.

Paper Title Page
MOPD094 Single Bunch Operation at ANKA: Gun Performance, Timing and First Results 924
 
  • A. Hofmann, I. Birkel, M. Fitterer, S. Hillenbrand, N. Hiller, E. Huttel, V. Judin, M. Klein, S. Marsching, A.-S. Müller, N.J. Smale, K.G. Sonnad, P.F. Tavares
    KIT, Karlsruhe
 
 

A new 90 kV e-gun had been installed at the 50 MeV microtron at ANKA. The emittance of the gun has been measured in long pulse mode (1 us, 200 mA) with a pepper-pot, resulting in 5 u.rad RMS normalised emittance. The single pulse width is less than 1 ns, resulting in a bunch purity in the storage ring of better 0.5 %. The old timing system for gun and injection elements based on 4 Stanford delay generator has now been replaced by an event driven system from Micro-Research Finland (MRF). This consists of one event generator and one event receiver. Visualisation and programming is achieved with PVSS from ETM Austria. The e-gun trigger can be adjusted in 10 ps steps. The entire system is phase locked to the 499.69 MHz RF signal.

 
TUPD005 Analysis of THz spectra and bunch deformation caused by CSR at ANKA 1925
 
  • M. Klein, N. Hiller, P.F. Tavares
    KIT, Karlsruhe
  • A.-S. Müller, K.G. Sonnad
    FZK, Karlsruhe
 
 

The ANKA light source is regularly operated with a low momentum compaction factor lattice where short bunches are created for the generation of coherent synchrotron radiation (CSR). Short bunches with high electron density can generate strong self fields which act back on the bunch. This can lead to bunch shape deformation and a microbunching instability which were studied theoretically for the ANKA low alpha parameters (Klein et al. PAC 09). We extended these studies to a comparison of calculated electron distributions and bunch profiles measured with a streak camera. The Haissinski equation was solved for the CSR impedance to obtain a prediction for the distortion of the bunches for different bunch lengths and bunch currents. The comparison shows that the theory predicts a much stronger deformation caused by CSR than the streak camera observes. However, high frequency components of measured FTIR spectra show a clear indication for strong deformation or small

 
TUPD027 Beam Coupling Impedance Measurements at the ANKA Electron Storage Ring 1982
 
  • P.F. Tavares
    Karlsruhe Institute of Technology (KIT), Karlsruhe
  • M. Fitterer, N. Hiller, A. Hofmann, V. Judin, M. Klein, S. Marsching, N.J. Smale, K.G. Sonnad
    KIT, Karlsruhe
  • E. Huttel, A.-S. Müller
    FZK, Karlsruhe
  • P.F. Tavares
    LNLS, Campinas
 
 

We present results of a series of measurements aimed at characterizing the beam coupling impedances in the ANKA electron storage ring. The measurements include transverse coherent tune shifts, bunch lengthening and synchronous phase shift as a function of single bunch current. These were performed under a variety of conditions in the ANKA ring, including injection energy (500 MeV), nominal operating energy (2.5 GeV) as well as at 1.3 GeV and in the low alpha mode and are part of a longer term effort to understand the ANKA impedance over a wide frequency range.

 
WEPEA019 Beam Studies for TBONE 2520
 
  • S. Hillenbrand, M. Fitterer, N. Hiller, A. Hofmann, E. Huttel, V. Judin, M. Klein, S. Marsching, A.-S. Müller, K.G. Sonnad, P.F. Tavares
    KIT, Karlsruhe
 
 

The Karlsruhe Institute of Technology (KIT) proposes to build a new light source called TBONE (THz Beam Optics for New Experiments), which aims at a spectral range from 0.1 to 150 THz with a peak power of several MW and a pulse length of only 5 fs. In order to achieve this, a beam transport system with minimal losses and a high bunch compression is required. In this paper we present first beam dynamic simulations of the superconducting linac as well as the bunch compressor and give a short status report of the TBONE project.

 
WEPEA020 Observation of Bunch Deformation at the ANKA Storage Ring 2523
 
  • N. Hiller, S. Hillenbrand, A. Hofmann, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, A.-S. Müller, A. Plech, N.J. Smale, K.G. Sonnad, P.F. Tavares
    KIT, Karlsruhe
 
 

A dedicated optics with a low momentum compaction factor is used at the ANKA storage ring to reduce the bunch length to generate coherent synchrotron radiation (CSR). A double sweep streak camera is employed to determine the bunch length and shape for different optics and as a function of the beam current. Measurements of the longitudinal bunch profile have been performed for many different momentum compaction factors and various bunch currents. This paper describes the set up of the streak camera experiments and compares the measured bunch lengths to theoretical expectations.

 
WEPEA021 Observation of Bursting Behavior Using Multiturn Measurements at ANKA 2526
 
  • V. Judin, S. Hillenbrand, N. Hiller, A. Hofmann, E. Huttel, M. Klein, S. Marsching, A.-S. Müller, N.J. Smale, K.G. Sonnad, P.F. Tavares
    KIT, Karlsruhe
  • H.W. Huebers
    Technische Universität Berlin, Berlin
  • A. Semenov
    DLR, Berlin
 
 

Since a few years CSR-Radiation created in low alpha mode is provided by the ANKA light source of the KIT*. Depending on the bunch current, the radiation is emitted in bursts of high intensity. These bursts display a time evolution which can be observed only on long time scales with respect to the revolution period. The intensity of the emitted radiation during a burst is significantly increased w.r.t. steady state emission. Some users of the THz radiation don't require particularly constant emission characteristics and could profit from the higher intensity. A better understanding of the long term behaviour of those bursts could help to improve the conditions for those users. We have investigated THz radiation in multiturn mode with a hot electron bolometer. Its time response of 165ps allowed us to resolve the signals of individual bunches. Using a 6GHz LeCroy oscilloscope for data acquisition, we were able to save up to 1.6ms long signal sequences at a sampling rate of 20GS/s. This amount of data corresponds to over 4000 bunch revolutions and allows turn-by-turn signal tracking of desired bunches. In single bunch mode we are able to take segmented data to avoid a huge overhead.


* KIT - Karlsruhe Institute for Technology

 
WEPEA022 Studies of Polarisaion of Coherent THz Edge Radiation at the ANKA Storage Ring 2529
 
  • A.-S. Müller, I. Birkel, M. Fitterer, S. Hillenbrand, N. Hiller, A. Hofmann, E. Huttel, K.S. Ilin, V. Judin, M. Klein, S. Marsching, Y.-L. Mathis, P. Rieger, M. Siegel, N.J. Smale, K.G. Sonnad, P.F. Tavares
    KIT, Karlsruhe
  • H.W. Huebers
    Technische Universität Berlin, Berlin
  • A. Semenov
    DLR, Berlin
 
 

In synchrotron radiation sources coherent radiation is emitted when the bunch length is comparable to or shorter than the wavelength of the emitted radiation. At the ANKA storage ring this radiation is observed as so-called edge radiation (emitted in the fringe field of a bending magnet). This radiation exhibits a radial polarisation pattern. The observed pattern, however, is influenced by the radiation transport in the beam line. A detector system based on a superconducting NbN ultra-fast bolometer with an intrinsic response time of about 100 ps as well as conventional Si bolometers were used to study the beam polarisaion. This paper reports the observations made during measurements.

 
TUPEB034 Interaction Region Design for a Ring Ring Version of the LHeC Study 1596
 
  • B.J. Holzer, S. Bettoni, O.S. Brüning, S. Russenschuck
    CERN, Geneva
  • R. Appleby
    UMAN, Manchester
  • J.B. Dainton, L.N.S. Thompson
    Cockcroft Institute, Warrington, Cheshire
  • M. Klein
    The University of Liverpool, Liverpool
  • A. Kling, B. Nagorny, U. Schneekloth
    DESY, Hamburg
  • P. Kostka
    DESY Zeuthen, Zeuthen
  • A. Polini
    INFN-Bologna, Bologna
 
 

The LHeC aims at colliding hadron-lepton beams with center of mass energies in the TeV scale. For this purpose the existing LHC storage ring is extended by a high energy electron accelerator in the energy range of 60 to 140 GeV. The electron beam will be accelerated and stored in a LEP like storage ring in the LHC tunnel. In this paper we present the layout of the interaction region which has to deliver at the same time well matched beam optics and an efficient separation of the electron and proton beams. In general the large momentum difference of the two colliding beams provides a very elegant way to solve this problem: A focusing scheme that leads to the required beam sizes of the electrons and protons is combined with an early but gentle beam separation to avoid parasitic beam encounters and still keep the synchrotron radiation level in the IR within reasonable limits. We present in this paper two versions of this concept: A high luminosity layout where the mini beta magnets are embedded into the detector design as well as an IR design that is optimised for maximum acceptance of the particle detector.

 
TUPEB039 Designs for a Linac-Ring LHeC 1611
 
  • F. Zimmermann, O.S. Brüning, E. Ciapala, F. Haug, J.A. Osborne, D. Schulte, Y. Sun, R. Tomás
    CERN, Geneva
  • C. Adolphsen
    SLAC, Menlo Park, California
  • R. Calaga, V. Litvinenko
    BNL, Upton, Long Island, New York
  • S. Chattopadhyay
    Cockcroft Institute, Warrington, Cheshire
  • J.B. Dainton, M. Klein
    The University of Liverpool, Liverpool
  • A.L. Eide
    LPNHE, Paris
 
 

We consider three different scenarios for the recirculating electron linear accelerator (RLA) of a linac-ring type electron-proton collider based on the LHC (LHeC): i) a basic version consisting of a 60 GeV pulsed, 1.5 km long linac, ii) a higher luminosity configuration with a 60 GeV 4 km long cw energy-recovery linac (ERL), and iii) a high energy option using a 140 GeV pulsed linac of 4 km active length. This paper describes the footprint, optics of linac and return arcs, emittance growth from chromaticity and synchrotron radiation, a set of parameters, and the performance reach for the three scenarios.

 
TUPEB037 Interaction-Region Design Options for a Linac-Ring LHeC 1605
 
  • F. Zimmermann, S. Bettoni, O.S. Brüning, B.J. Holzer, S. Russenschuck, D. Schulte, R. Tomás
    CERN, Geneva
  • H. Aksakal
    N.U, Nigde
  • R. Appleby
    UMAN, Manchester
  • S. Chattopadhyay, M. Korostelev
    Cockcroft Institute, Warrington, Cheshire
  • A.K. Çiftçi, R. Çiftçi, K. Zengin
    Ankara University, Faculty of Sciences, Tandogan/Ankara
  • J.B. Dainton, M. Klein
    The University of Liverpool, Liverpool
  • E. Eroglu, I. Tapan
    UU, Bursa
  • P. Kostka
    DESY Zeuthen, Zeuthen
  • V. Litvinenko
    BNL, Upton, Long Island, New York
  • E. Paoloni
    University of Pisa and INFN, Pisa
  • A. Polini
    INFN-Bologna, Bologna
  • U. Schneekloth
    DESY, Hamburg
  • M.K. Sullivan
    SLAC, Menlo Park, California
 
 

In a linac-ring electron-proton collider based on the LHC ("LR-LHeC"), the final focusing quadrupoles for the electron beam can be installed far from the collision point, as far away as the proton final triplet (e.g. 23 m) if not further, thanks to the small electron-beam emittance. The inner free space could either be fully donated to the particle-physics detector, or accommodate "slim" dipole magnets providing head-on collisions of electron and proton bunches. We present example layouts for either scenario considering electron beam energies of 60 and 140 GeV, and we discuss the optics for both proton and electron beams, the implied minimum beam-pipe dimensions, possible design parameters of the innermost proton and electron magnets, the corresponding detector acceptance, the synchrotron radiation power and its possible shielding or deflection, constraints from long-range beam-beam interactions as well as from the LHC proton-proton collision points and from the rest of the LHC ring, the passage of the second proton beam, and the minimum beta* for the colliding protons.