Author: Joseph J. BisognanoPublisher:
ISBN:
Category :
Languages : en
Pages : 6
Book Description
Multipass Beam Breakup in Recirculating Linacs
Author: Joseph J. BisognanoBeam Breakup in Recirculating Linacs
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 2483
Book Description
In general, a recirculation path length in a recirculating accelerator has to be an integer multiple of RF wavelength if recirculations are all in the same direction. However, it is not necessary to require such a relation to be satisfied with respect to the bunching frequency, when the bunch repetition rate is different from the RF frequency. An analytic model of multipass beam breakup (BBU) in recirculating linacs studied by Bisognano and Gluckstern has been generalized to include the case of a subharmonic bunching scheme in the operation of such linacs.
A METHOD TO CONTROL MULTIPASS BEAM BREAKUP IN RECIRCULATING LINACS.
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We investigate a method to control the multipass dipole beam breakup instability in a recirculating linac including energy recovery. Effectiveness of an external feedback system for such a goal is shown clearly in a simplified model. We also verify the theoretical result with a simulation study.
Tools to Predict Beam Breakup in Recirculating Linacs
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 3
Book Description
An important limitation on the maximum beam current in a recirculating linac is due to beam breakup caused by higher order modes (HOM) excited in the RF cavities. A HOM delivers a transverse kick to a beam bunch, the bunch on the next pass can then drive the HOM and cause it to grow until the beam is lost. Two codes, MATBBU1 and TDBBU2, have been written to estimate the threshold current for a set of HOMs and accelerator optics. The relative merits and limitations of each is discussed in detail.
Multipass Beam Breakup in Recirculating Linacs
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 2060
Book Description
Multipass beam breakup, a transverse beam instability generated by coherent excitation of cavity higher order modes in a recirculating linac, is a particular concern in designs utilizing superconducting technology. In this paper, an analytic model is presented that includes a description of this effect for a distribution of cavities along the linac with several recirculations in an impulse approximation. For N passes and M cvities, solution of the resulting equations reduces in general to finding M zeros of a 2(N-1) dimensional determinant or equivalently the M eigenvalues of an M-dimensional matrix. The parametric dependence of this system on higher order mode frequencies and Q, lattice functions, and transit times is discussed. Numerical examples are presented to clarify these issues and to model the CEBAF superconducting linac, where threshold currents are found to exceed design currents by more than an order of magnitude.
A Cure for Multipass Beam Breakup in Recirculating Linacs
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We investigate a method to control the multipass dipole beam breakup instability in a recirculating linac including energy recovery. Effectiveness of an external feedback system for such a goal is shown clearly in a simplified model. We also verify the theoretical result with a simulation study.
Beam Breakup in Recirculating Linacs, February 1990
Author: Byung YunnBeam Breakup in Superconducting Recirculating Linacs
Author: Publisher:
ISBN:
Category :
Languages : en
Pages : 5
Book Description
The performance and operational flexibility of superconducting recirculating linacs can be limited by a variety of collective phenomena which are grouped under the name beam breakup. In this note the various beam breakup phenomena found in recirculating superconducting radio frequency linacs are described and appraised relative to beam performance.
Multipass Beam Breakup in Recirculating Linacs, July 1986
Author: Joseph J. BisognanoExpressions for the Threshold Current of Multipass Beam Breakup in Recirculating Linacs from Single Cavity Models
Author: Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
We investigate multipass beam breakup (BBU) in a recirculating linear accelerator in the framework of a single cavity model. We present expressions for the beam breakup threshold current for various situations derived from a perturbative solution of BBU equations. These formulae should serve as a guide to understand the BBU phenomenon for a particular system and also as a tool to estimate the BBU threshold current quickly. Many of the results presented are more general than previous considerations because they include the effects of coupling between the two transverse polarizations in each dipole higher order mode.