Segmented undulator operation at the SPARC-FEL test facility

Franco Ciocci, Maria Pia Anania, Marcello Artioli, Marco Bellaveglia, Mariano Carpanese, Enrica Chiadroni, Alessandro Cianchi, Giuseppe Dattoli, Domenico Di Giovenale, Emanuele Di Palma, Giampiero Di Pirro, Massimo Ferrario, Andrea Mostacci, Alberto Petralia, Vittoria Petrillo, Riccardo Pompili, Elio Sabia, Ivan Spassovsky, Vincenzo Surrenti, Cristina VaccarezzaFabio Villa

Research output: Contribution to conferencePaper


A short period undulator (1.4 cm) has been designed for the SPARC-FEL test facility and has been realized in collaboration with KYMA Srl. It has been installed on the undulator line at SPARC. The undulator, operating in a delta like mode, has been used as radiator in a segmented configuration. The first stage being provided by the five undulators of the SPARC FEL source "old" chain, with period 2.8 cm. The KYMA undulator has a quatrefoil structure, a high magnetic field homogeneity and focuses both in vertical and radial directions. The two sections, namely the bunching and radiating parts, are arranged in such a way that the second is adjusted on a harmonic of the first. Laser action occurring in the second part, is due to the bunching acquired in the first. Simulations of the temporal and spectral profiles in different electron beam operating conditions are reported, as well as the evolution of the longitudinal phase space. The agreement with the experimental results is discussed The importance of this experiment is at least threefold: 1) It proves that the segmented undulator can successfully be operated 2) It proves that the laser emission in the last undulator is entirely due to the bunching mechanism, being no second harmonic signal present in the first segment 3) Encourages various improvements of the configuration itself, as e.g. the use of a further undulator with variable magnetic field configuration in order to obtain a laser field with adjustable polarization.
Original languageEnglish
Publication statusPublished - 2015
Externally publishedYes
EventAdvances in X-Ray Free-Electron Lasers Instrumentation III - Prague, Czech Republic
Duration: 1 Jan 2015 → …


ConferenceAdvances in X-Ray Free-Electron Lasers Instrumentation III
CountryCzech Republic
Period1/1/15 → …


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Cite this

Ciocci, F., Anania, M. P., Artioli, M., Bellaveglia, M., Carpanese, M., Chiadroni, E., ... Villa, F. (2015). Segmented undulator operation at the SPARC-FEL test facility. Paper presented at Advances in X-Ray Free-Electron Lasers Instrumentation III, Prague, Czech Republic.