dorsal/arxiv
View SchemaUndulator Radiation in a Waveguide
| Authors | Gianluca Geloni, Evgeni Saldin, Evgeni Schneidmiller, Mikhail Yurkov |
|---|---|
| Categories | |
| ArXiv ID | physics/0703049 |
| URL | https://arxiv.org/abs/physics/0703049 |
| DOI | 10.1016/j.nima.2007.10.016 |
| Journal | Nucl.Instrum.Meth.A584:219-237,2008 |
Abstract
We propose an analytical approach to characterize undulator radiation near resonance, when the presence of the vacuum-pipe considerably affects radiation properties. This is the case of the far-infrared undulator beamline at the Free-electron LASer (FEL) in Hamburg (FLASH), that will be capable of delivering pulses in the TeraHertz (THz) range. This undulator will allow pump-probe experiments where THz pulses are naturally synchronized to the VUV pulse from the FEL, as well as the development of novel electron-beam diagnostics techniques. Since the THz radiation diffraction-size exceeds the vacuum-chamber dimensions, characterization of infrared radiation must be performed accounting for the presence of a waveguide. We developed a theory of undulator radiation in a waveguide based on paraxial and resonance approximation. We solved the field equation with a tensor Green's function technique, and extracted figure of merits describing in a simple way the influence of the vacuum-pipe on the radiation pulse as a function of the problem parameters. Our theory, that makes consistent use of dimensionless analysis, allows treatment and physical understanding of many asymptotes of the parameter space, together with their region of applicability.
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"abstract": "We propose an analytical approach to characterize undulator radiation near\nresonance, when the presence of the vacuum-pipe considerably affects radiation\nproperties. This is the case of the far-infrared undulator beamline at the\nFree-electron LASer (FEL) in Hamburg (FLASH), that will be capable of\ndelivering pulses in the TeraHertz (THz) range. This undulator will allow\npump-probe experiments where THz pulses are naturally synchronized to the VUV\npulse from the FEL, as well as the development of novel electron-beam\ndiagnostics techniques. Since the THz radiation diffraction-size exceeds the\nvacuum-chamber dimensions, characterization of infrared radiation must be\nperformed accounting for the presence of a waveguide. We developed a theory of\nundulator radiation in a waveguide based on paraxial and resonance\napproximation. We solved the field equation with a tensor Green\u0027s function\ntechnique, and extracted figure of merits describing in a simple way the\ninfluence of the vacuum-pipe on the radiation pulse as a function of the\nproblem parameters. Our theory, that makes consistent use of dimensionless\nanalysis, allows treatment and physical understanding of many asymptotes of the\nparameter space, together with their region of applicability.",
"arxiv_id": "physics/0703049",
"authors": [
"Gianluca Geloni",
"Evgeni Saldin",
"Evgeni Schneidmiller",
"Mikhail Yurkov"
],
"categories": [
"physics.optics",
"physics.acc-ph"
],
"doi": "10.1016/j.nima.2007.10.016",
"journal_ref": "Nucl.Instrum.Meth.A584:219-237,2008",
"title": "Undulator Radiation in a Waveguide",
"url": "https://arxiv.org/abs/physics/0703049"
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