72 citations · 138 across the 21 of their papers we have counts for
21 papers
Conceptual design of a mid-energy spin rotator for continuous-wave operation based on a compact multi-pi rosetta magnet
Volker Ziemann
Spin-rotators in the the few-MeV range require large trajectory deflection angles in order to change the spin direction appreciably. We describe a magnet system that accumulates ad…
Wien-Filter Hamiltonian and Transfer Matrix
Volker Ziemann
We derive the Hamiltonian and the transfer matrix of a Wien-filter with vertical magnetic field from first principles.
Real-time system identification of superconducting cavities with a recursive least-squares algorithm: closed-loop operation
Volker Ziemann
We simulate a recursive least-squares estimator to determine the bandwidth and the detuning of a cavity that is controlled with a low-level RF system and we present a…
Operational improvements for an algorithm to noninvasively measure the orbit response matrix in storage rings
Volker Ziemann
We improve the algorithm to noninvasively update the response matrix using information from the orbit-feedback system, described in [1]. The new version is capable of adapting to s…
Emittance growth of kicked and mismatched beams due to amplitude-dependent tune shift
E. Waagaard, V. Ziemann
We derive evolution equations for the first and second moments of an initially mismatched, coupled, and displaced arbitrary Gaussian phase-space distribution under the influence of…
Equilibrium parameters in coupled storage ring lattices and practical applications
Volker Ziemann, Andreas Streun
We calculate equilibrium emittances and damping times due to the emission of synchrotron radiation for coupled storage ring lattices by evaluating the projections of the commonly u…
RF gymnastics with transfer matrices
Volker Ziemann
We introduce transfer matrices to describe the motion of particles in the vicinity of the stable and unstable fixed points of longitudinal phase space and use them to analyze the t…
Beam parameters of a Möbius ring
Volker Ziemann
We describe a racetrack-shaped ring in which the cross-plane coupling can be continuously varied between an uncoupled configuration to a Möbius configuration, where the transverse…
Longitudinal phase-space matching between radio-frequency systems with different harmonic numbers and accelerating voltages
Volker Ziemann
We describe a simple mechanism to transform bunches with matched longitudinal phase-space distributions from one RF system to a matched distribution of a second RF system operating…
Strap-on magnets: a framework for rapid prototyping of magnets and beam lines
Volker Ziemann
We describe a framework to assemble permanent-magnet cubes in 3D-printed frames to construct dipole, quadrupole, and solenoid magnets, whose field, in the absence of iron, can be c…
Closed-form expressions for the magnetic field of permanent magnets in three dimensions
Volker Ziemann
We derive a closed-form expression of the magnetic field of a finite-size current sheet and use it to calculate the field of permanent magnets, which are modeled through their surf…
MATLAB Simulations of the Helium Liquefier in the FREIA Laboratory
Elias Waagaard, Roger Ruber, Volker Ziemann
We describe simulations that track a state vector with pressure, temperature, and gas flow through the helium liquefier in the FREIA laboratory. Most components, including threeway…
Noninvasively improving the orbit-response matrix while continuously correcting the orbit
Ingvar Ziemann, Volker Ziemann
Based on continuously recorded beam positions and corrector excitations from, for example, a closed-orbit feedback system we describe an algorithm that continuously updates an esti…
Accelerator Development at the FREIA Laboratory
R. Ruber, A. K. Bhattacharyya, D. Dancila +22
The FREIA Laboratory at Uppsala University focuses on superconducting technology and accelerator development. It actively supports the development of the European Spallation Source…
Imperfections and Corrections
V. Ziemann
After a review of linear imperfections and their causes, we discuss how to model them, the diagnostic equipment needed to monitor them, and the correction algorithms to fix the pro…
Beam Optics Primer using Octave or MATLAB
V. Ziemann
This primer provides a basic introduction to beam optics concepts that are commonly used to describe charged particle accelerators.
Envelope Dynamics and Stability with non-linear Space-Charge Forces
Michael Holz, Volker Ziemann
We developed a model to calculate the stability of Gaussian beam distributions with non-linear space-charge forces in the presence of random and skew-quadrupole errors. The effect…
The Compact Linear ee Collider (CLIC): Physics Potential
P. Roloff, R. Franceschini, U. Schnoor +1
The Compact Linear Collider, CLIC, is a proposed ee collider at the TeV scale whose physics potential ranges from high-precision measurements to extensive direct sensitivit…
Luminosity Loss due to Kicks and Mismatch from radio-frequency breakdown in a Linear Collider
Volker Ziemann
We calculate the geometric luminosity loss caused by filamentation of transverse kicks, upright and skew quadrupolar errors due to discharges, so-called RF-breakdown, in the accele…
Updated baseline for a staged Compact Linear Collider
The CLIC, CLICdp collaborations, : +515
The Compact Linear Collider (CLIC) is a multi-TeV high-luminosity linear e+e- collider under development. For an optimal exploitation of its physics potential, CLIC is foreseen to…
Stimulated coherent spontaneous emission in an FEL with `quiet' bunches
V. A. Goryashko, V. Ziemann
For a planar FEL configuration we study stimulated coherent spontaneous emission driven by a gradient of the bunch current in the presence of different levels of noise in bunches.…