FEL2014 - List of Keywords (beam-transport)

Paper	Title	Other Keywords	Page
MOP010	The Photon Beam Loss Monitors as a Part of Equipment Protection System at European XFEL	photon, detector, vacuum, radiation	37
	N. Gerasimova, H. Sinn XFEL. EU, Hamburg, Germany S. Dziarzhytski, R. Treusch DESY, Hamburg, Germany
	For the X-ray beam transport systems, the problem of potential damage to the equipment by mis-steered photon beam emerged with advent of powerful X-ray FELs. In particular high repetition rate machines as European XFEL, where not only focused beam can produce ablation, but even unfocused beam can melt the beamline components while machine operates in multibunch mode, demand for implementation of equipment protection. Here we report on development of photon beam loss monitors at European XFEL facility. The photon beam loss monitors will react on the mis-steered photon beam and interface the machine protection system. The prototype comprises the vacuum chamber with fluorescence crystals positioned outside the photon beampath. The fast sub-hundred ns fluorescence induced by mis-steered beam can be detected by photomultiplier tube allowing for intra-train reaction of machine protection system. First tests have been carried out at FLASH and shown the feasibility of detection based on PMT-detected fluorescence. In addition to efficient YAG:Ce crystal, the robust low-Z material as CVD microcrystalline diamonds has shown a potential to be used as fluorescence crystals.

THP023	Simulation of Alpha Magnet Elements in Dipole-only Tracking Codes	dipole, simulation, electron, coupling	735
	J.W. Lewellen, F.L. Krawczyk LANL, Los Alamos, New Mexico, USA
	Alpha magnets are used in a variety of ion-beam and low-energy (< 5 MeV) electron-beam transport systems as both “switchyard” elements and as bunch compressors. A unique feature of the alpha-magnet is its natively achromatic transport. Particles of different energies, injected at a specific location and angle, will exit at the same location and (symmetry-reflected) angle but with a different time-of-flight. Despite the general usefulness of alpha magnets in low-energy beam transport and compression schemes, few simulation codes support them as native elements. The (arguably) most-common codes used for injector design, PARMELA, ASTRA and GPT (listed in order of their release) do not support alpha magnets natively, but do support modeling of space-charge-dominated beams through dipole magnets. As a result, the most commonly used injector design codes are unable to incorporate one of the most useful and interesting beam transport devices. We present a method for simulating an alpha magnet in a tracking code using dipole elements. As elegant supports both dipoles and alpha magnets, it is used to provide a basic check of the approximation and a means of estimating the induced errors.

Paper

Title

Other Keywords

Page

MOP010

The Photon Beam Loss Monitors as a Part of Equipment Protection System at European XFEL

photon, detector, vacuum, radiation

37

N. Gerasimova, H. Sinn
XFEL. EU, Hamburg, Germany
S. Dziarzhytski, R. Treusch
DESY, Hamburg, Germany

For the X-ray beam transport systems, the problem of potential damage to the equipment by mis-steered photon beam emerged with advent of powerful X-ray FELs. In particular high repetition rate machines as European XFEL, where not only focused beam can produce ablation, but even unfocused beam can melt the beamline components while machine operates in multibunch mode, demand for implementation of equipment protection. Here we report on development of photon beam loss monitors at European XFEL facility. The photon beam loss monitors will react on the mis-steered photon beam and interface the machine protection system. The prototype comprises the vacuum chamber with fluorescence crystals positioned outside the photon beampath. The fast sub-hundred ns fluorescence induced by mis-steered beam can be detected by photomultiplier tube allowing for intra-train reaction of machine protection system. First tests have been carried out at FLASH and shown the feasibility of detection based on PMT-detected fluorescence. In addition to efficient YAG:Ce crystal, the robust low-Z material as CVD microcrystalline diamonds has shown a potential to be used as fluorescence crystals.

THP023

Simulation of Alpha Magnet Elements in Dipole-only Tracking Codes

dipole, simulation, electron, coupling

735

J.W. Lewellen, F.L. Krawczyk
LANL, Los Alamos, New Mexico, USA

Alpha magnets are used in a variety of ion-beam and low-energy (< 5 MeV) electron-beam transport systems as both “switchyard” elements and as bunch compressors. A unique feature of the alpha-magnet is its natively achromatic transport. Particles of different energies, injected at a specific location and angle, will exit at the same location and (symmetry-reflected) angle but with a different time-of-flight. Despite the general usefulness of alpha magnets in low-energy beam transport and compression schemes, few simulation codes support them as native elements. The (arguably) most-common codes used for injector design, PARMELA, ASTRA and GPT (listed in order of their release) do not support alpha magnets natively, but do support modeling of space-charge-dominated beams through dipole magnets. As a result, the most commonly used injector design codes are unable to incorporate one of the most useful and interesting beam transport devices. We present a method for simulating an alpha magnet in a tracking code using dipole elements. As elegant supports both dipoles and alpha magnets, it is used to provide a basic check of the approximation and a means of estimating the induced errors.