The Joint Accelerator Conferences Website (JACoW) is an international collaboration that publishes the proceedings of accelerator conferences held around the world.
TY - CONF AU - Kubarev, V.V. AU - Bae, S. AU - Getmanov, Ya.V. AU - Jeong, Y.U. AU - Shevchenko, O.A. ED - Schaa, Volker R.W. ED - Decking, Winfried ED - Sinn, Harald ED - Geloni, Gianluca ED - Schreiber, Siegfried ED - Marx, Michaela TI - Fine and Hyperfine Structure of FEL Emission Spectra J2 - Proc. of FEL2019, Hamburg, Germany, 26-30 August 2019 CY - Hamburg, Germany T2 - Free Electron Laser Conference T3 - 39 LA - english AB - This paper presents the results of experimental investigations of the fine and hyperfine spectral structures of the Novosibirsk free-electron laser (NovoFEL) and the compact free-electron laser of the Korea Atomic Energy Research Institute (KAERI FEL) by means of the optimal instruments, resonance Fabry-Perot interferometers. The very high coherence of the NovoFEL spectrum was measured in regimes with one pulse circulating inside its optical resonator (the coherence length is 7 km, and the relative width of the hyperfine structure lines is 2E-8) and with total absence of coherence between two circulating pulses, i.e. the fine structure. Sixty pulses circulate simultaneously inside the KAERI FEL optical resonator, and the measured coherence length on average covers ten pulses (the coherence length is 1 m; the relative width of the fine structure lines is 10⁻⁴). PB - JACoW Publishing CP - Geneva, Switzerland SP - 276 EP - 281 KW - FEL KW - electron KW - radiation KW - laser KW - experiment DA - 2019/11 PY - 2019 SN - "" SN - 978-3-95450-210-3 DO - doi:10.18429/JACoW-FEL2019-TUD03 UR - http://jacow.org/fel2019/papers/tud03.pdf ER -