TY - CONF AU - Telawane, S. AU - Schöps, A. AU - Neumann, Paul AU - Ramm, T. AU - Tischer, M. AU - Vagin, P. TI - A Laser Heater Undulator for FLASH2020+ JO - Journal of physics / Conference Series VL - 2380 IS - 1 SN - 1742-6588 CY - Bristol PB - IOP Publ. M1 - PUBDB-2023-01311 SP - 012028 PY - 2023 AB - Space charge induced micro bunch instabilities, amplified in cascadedbunch compression stages, spoil the phase space of compressed bunches and leadto unstable seeding. To “heat” up the bunch with an external laser and induce anuncorrelated energy spread to suppresses the micro bunching instabilities, a shortundulator will be installed in front of the first compression chicane. The undulator hasa planar hybrid magnet structure with 43 mm period length, 11 full periods, 22 mmminimum gap and a deflection parameter K of 1.52 (K = (eBλ<sub>u</sub>) / (2πm<sub>ec</sub>), withB - max. magnetic field amplitude, λ<sub>u</sub> - period length) to match the 534 nm laserwavelength at 146 MeV beam energy. The paper describes the undulator’s compactdesign, its control system and results of magnetic measurements and tuning. T2 - 14th International Conference on Synchrotron Radiation Instrumentation CY - 28 Mar 2022 - 1 Apr 2022, Hamburg (Germany) Y2 - 28 Mar 2022 - 1 Apr 2022 M2 - Hamburg, Germany LB - PUB:(DE-HGF)16 ; PUB:(DE-HGF)8 DO - DOI:10.1088/1742-6596/2380/1/012028 UR - https://bib-pubdb1.desy.de/record/580554 ER -