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Lajos Bojtár

Publications and source records attributed to Lajos Bojtár.

2 recordsLinked to original sources
arXiv2020

Frequency analysis and dynamic aperture studies in ELENA with realistic 3D magnetic fields

We briefly present recent progress with our algorithm and its implementation called SIMPA described in a previous paper. The algorithm has a new and unique approach to long-term 4D tracking of charged particles in arbitrary static electromagnetic fields. Using the improvements described in this paper, we made frequency analysis and dynamic aperture studies in ELENA. The effect of the end fields and the perturbation introduced by the magnetic system of the electron cooler on dynamic aperture is shown. A special feature of this study is that we have not introduced any multipole errors into the model. The dynamic aperture calculated in this paper is the direct consequence of the geometry of the magnetic elements. Based on the results, we make a few suggestions to reduce the losses during the deceleration of the beam.

physics.acc-ph↗
arXiv2008

Transverse-Longitudinal Emittance Transfer in Circular Accelerators Revised

We revise a previous version of this paper proposing a method to transfer emittances from the transverse planes to the longitudinal. It turned out the system showed non-Hamiltonian behavior because the longitudinal component of the transverse electric field at ends of the transverse resonator were not included in the model. Including those fields the 6D emittance is conserved. We review the mechanism behind the emittance conservation. It is still possible to produce an emittance transfer with the RF quadrupole field setting the tunes on synchro-betatron resonance for a short period of time then reducing the transverse RF field to zero. We found some coupling between the transverse and the longitudinal planes is always present, even there in no special device in the accelerator to provoke it. The role of the transverse RF field is to modify the transverse tunes quickly putting the system to synchro-betatron resonance for a short time. The emittance tends to flow from the plane with bigger emittance to the smaller one.

physics.acc-ph↗