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[en] This note presents the fiducialization plan for the LCLS undulator quadrupoles. The note begins by summarizing the requirements for the fiducialization. A discussion of the measurement equipment is presented, followed by the methods used to perform the fiducialization and check the results. This is followed by the detailed fiducialization plan in which each step is enumerated. Finally, the measurement results and data storage formats are presented. The LCLS is made up of 33 assemblies consisting of an undulator, quadrupole, beam finder wire, and other components mounted on a girder. The components must be mounted in such a way that the beam passes down the axis of each component. In this note, we describe how the ideal beam axis is related to tooling balls on the quadrupole. This step, called fiducialization, is necessary because the ideal beam axis is determined magnetically, whereas tangible objects must be used to locate the quadrupole. The note begins with the list of fiducialization requirements. The laboratory in which the work will be performed and the relevant equipment is then briefly described. This is followed by a discussion of the methods used to perform the fiducialization and the methods used to check the results. A detailed fiducialization plan is presented in which all the steps of fiducialization are enumerated. A discussion of the resulting data files and directory structure concludes the note.
[en] A method for numerically recovering the coherent modes and their occupancies from a known mutual optical intensity function is described. As an example, the technique is applied to previously published experimental data from an x-ray undulator source. The data are found to be described by three coherent modes, and the functional forms and relative occupancies of these modes are recovered.
[en] The main features of synchrotron radiation (SR) procedured by insertion devices are presented, discussed, and compared to the SR spectrum generated by bending magnets. (A.C.A.S.)
[pt]As principais caracteristicas da radiacao sincrotron produzidas por dispositivos de insercao sao apresentadas, discutidas e comparadas a espectros gerados por imas de curvatura. (A.C.A.S.)
[en] A non linear analysis of a new free electron laser oscillator configuration is presented. Procedures and design examples for both tapered and untapered 300 GHz 1.0 MW Fel oscillators are determined and discussed. (A.C.A.S.)
[pt]Uma analise nao linear de um laser de eletrons livres e apresentada. Procedimentos e exemplos de desenhos para ambos osciladores, delgados e nao delgados de 300GHz, 1.0MW de laser de eletrons livres sao determinados e discutidos. (A.C.A.S.)
[en] The LCLS reference undulator has been measured 22 times during the course of undulator tuning. These measurements provide estimates of various statistical errors. This note gives a summary of the reference undulator measurements and it provides estimates of the undulator tuning errors. We measured the reference undulator many times during the tuning of the LCLS undulators. These data sets give estimates of the random errors in the tuned undulators. The measured trajectories in the reference undulator are stable and straight to within ±2 (micro)m. Changes in the phase errors are less than ±2 deg between data sets. The phase advance in the cell varies by less than ±2 deg between data sets. The rms variation between data sets of the first integral of Bx is 9.98 (micro)Tm, and the rms variation of the second integral of Bx is 17.4 (micro)Tm2. The rms variation of the first integral of By is 6.65 (micro)Tm, and the rms variation of the second integral of By is 12.3 (micro)Tm2. The rms variation of the x-position of the fiducialized beam axis is 35 (micro)m in the final production run This corresponds to an rms uncertainty in the K value of ΔK/K = 2.7 x 10-5. The rms variation of the y-position of the fiducialized beam axis is 4 (micro)m in the final production run.
[en] We simulate “zero-slippage” phase space manipulation driven by a guided THz pulse using the 3-D General Particle Tracer code and compare our results to analytical predictions for bunch compression and angular deflection. With the beam parameters available at the UCLA PEGASUS laboratory for a proof-of-concept experiment, we simulate compression by nearly a factor of 10. We compare two deflection mechanisms for transverse streaking with an emphasis on the 3-D effects introduced by the undulator field.
[en] There are still no helical undulators that satisfy all major requirements. A new helical undulator is described that has at least some of the properties that were not obtainable until now. It can be used in a synchrotron storage ring, is completely accessible from both sides, light with both helicities can be produced, the helical field can be made quite strong, and the period length can be adjusted over a small range. Similarly, there have been some efforts lately to develop undulators with very short periods. It is shown how a hybrid undulator with a period of the order 1 mm can be constructed