A   B   C   D   E   F   G   H   I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z  

Kreis, B.

Paper Title Page
MOPE090 CesrTA x-Ray Beam Size Monitor Operation 1194
 
  • D.P. Peterson, J.P. Alexander, C.J. Conolly, N. Eggert, E. Fontes, W.H. Hopkins, B. Kreis, A. Lyndaker, M.P. McDonald, M.A. Palmer, M.C. Rendina, P. Revesz, N.T. Rider, J.J. Savino, R.D. Seeley
    CLASSE, Ithaca, New York
  • J.W. Flanagan
    KEK, Ibaraki
 
 

We report on the design and operation of the CesrTA x-ray beam size monitor (xBSM). The xBSM resolution must be sufficient to measure vertical beam sizes of order 10um by imaging 2-4keV synchrotron radiation photons onto a one-dimensional photodiode array. Instrumentation in the evacuated x-ray beam line includes upstream interchangeable optics elements (slits, coded apertures, and Fresnel zone plates), a monochromator and an InGaAs photodiode detector. The readout is a beam-synchronized FADC that is capable of parallel measurement of consecutive bunches with 4ns spacing. The xBSM has been used to measure beam sizes during the August 2009, November 2009, and April 2010 runs. Single turn measurements are fit to characteristic image shapes to extract beam sizes independent of position variations. The turn-averaged beam size provides feedback for low-emittance tuning.

 
TUYMH02 Electron Cloud at Low Emittance in CesrTA 1251
 
  • M.A. Palmer, J.P. Alexander, M.G. Billing, J.R. Calvey, C.J. Conolly, J.A. Crittenden, J. Dobbins, G. Dugan, N. Eggert, E. Fontes, M.J. Forster, R.E. Gallagher, S.W. Gray, S. Greenwald, D.L. Hartill, W.H. Hopkins, D.L. Kreinick, B. Kreis, Z. Leong, Y. Li, X. Liu, J.A. Livezey, A. Lyndaker, J. Makita, M.P. McDonald, V. Medjidzade, R.E. Meller, T.I. O'Connell, S.B. Peck, D.P. Peterson, G. Ramirez, M.C. Rendina, P. Revesz, D.H. Rice, N.T. Rider, D. L. Rubin, D. Sagan, J.J. Savino, R.M. Schwartz, R.D. Seeley, J.W. Sexton, J.P. Shanks, J.P. Sikora, E.N. Smith, C.R. Strohman, H.A. Williams
    CLASSE, Ithaca, New York
  • F. Antoniou, S. Calatroni, M. Gasior, O.R. Jones, Y. Papaphilippou, J. Pfingstner, G. Rumolo, H. Schmickler, M. Taborelli
    CERN, Geneva
  • D. Asner
    Carleton University, College of Natural Sciences, Ottawa, Ontario
  • L. Boon, A.F. Garfinkel
    Purdue University, West Lafayette, Indiana
  • J.M. Byrd, C.M. Celata, J.N. Corlett, S. De Santis, M.A. Furman, A. Jackson, R. Kraft, D.V. Munson, G. Penn, D.W. Plate, M. Venturini
    LBNL, Berkeley, California
  • B.T. Carlson
    Grove City College, Grove City, Pennsylvania
  • T. Demma
    INFN/LNF, Frascati (Roma)
  • R.T. Dowd
    ASCo, Clayton, Victoria
  • J.W. Flanagan, P. Jain, K. Kanazawa, K. Kubo, K. Ohmi, H. Sakai, K. Shibata, Y. Suetsugu, M. Tobiyama
    KEK, Ibaraki
  • D. Gonnella
    Clarkson University, Potsdam, New York
  • W. Guo
    BNL, Upton, Long Island, New York
  • K.C. Harkay
    ANL, Argonne
  • R. Holtzapple
    CalPoly, San Luis Obispo, CA
  • J.K. Jones, A. Wolski
    Cockcroft Institute, Warrington, Cheshire
  • D. Kharakh, J.S.T. Ng, M.T.F. Pivi, L. Wang
    SLAC, Menlo Park, California
  • M.C. Ross, C.-Y. Tan, R.M. Zwaska
    Fermilab, Batavia
  • L. Schächter
    Technion, Haifa
  • E.L. Wilkinson
    Loyola University, Chicago, Illinois
 
 

The Cornell Electron Storage Ring (CESR) has been reconfigured as a test accelerator (CesrTA) for a program of electron cloud (EC) research at ultra low emittance. The instrumentation in the ring has been upgraded with local diagnostics for measurement of cloud density and with improved beam diagnostics for the characterization of both the low emittance performance and the beam dynamics of high intensity bunch trains interacting with the cloud. Finally a range of EC mitigation methods have been deployed and tested. Measurements of cloud density and its impact on the beam under a range of conditions will be presented and compared with simulations. The effectiveness of a range of mitigation techniques will also be discussed.

 

slides icon

Slides

 
MOPE007 Measurement of Low-Emittance Beam with Coded Aperture X Ray Optics at CesrTA 966
 
  • J.W. Flanagan, H. Fukuma, H. Ikeda, T.M. Mitsuhashi
    KEK, Ibaraki
  • J.P. Alexander, N. Eggert, W.H. Hopkins, M.A. Palmer, D.P. Peterson
    CLASSE, Ithaca, New York
  • B. Kreis
    Cornell University, Ithaca, New York
  • G.S. Varner
    UH, Honolulu, HI
 
 

An x-ray beam size monitor based on coded aperture imaging* has been developed at CesrTA, for the purpose of making bunch-by-bunch, turn-by-turn measurements of low emittance beams. Using low-emittance beam (~44 pm, or 16 microns at the x-ray source point) we have been able to make detailed comparisons between the measured mask response and that predicted by theory, validating our simulations of the mask response. In turn, we demonstrate the ability to measure both integrated and single-bunch turn-by-turn beam sizes and positions for monitoring the progress of the low-emittance tuning of the machine, and for electron-cloud instability-related beam dynamics studies.


* J.W. Flanagan et al., EPAC08, 1029 (2008).