No AP work has been done since the 2D-IR meeting. FEL work has reviewed differing options for the RF module and bunch repetition rate.
The latest agreed configuration (v1.2) is the original CDR configuration (2 FELs not operating together).
George Neil has made comments that JLab is considering some similar solutions (perhaps with Talahassee).
Perhaps this paper: http://www.bessy.de/fel2006/proceedings/PAPERS/TUPPH009.PDF
Having 2 FELs from one electron beam, the action of one FEL disturbs the electron beam for the next FEL. It is an open question whether these two FELs can output at the same wavelength (to be considered by Neil Thompson) - same-wavelength operation would allow 'on the diagonal' measurements to be made.
It could be possible to use only coherent emission from an undulator rather than an FEL - it is not clear whether an FEL would offer any pulse length advantage (i.e. can it generate shorter pulses than coherent emission alone?), or is this just a limit from the wavelength?
Post-meeting comment - of course, if we have coherent emission at a certain wavelength, then there is no point in having an FEL, as the cavity will not cause any microbunching. Recall that an FEL only works at wavelengths shorter than the bunch length; microbunching of a bunch can't occur at length scales bigger than the bunch (think about it - it doesn't make any sense!).
Christine Ramsdale has considered some of the controls/DAQ aspects.
Mark's notes:
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The full suite of FELs to provide complete coverage of the wavelength region requested by David Klug would not be available on day 1 but a phased introduction of facilities is envisaged.
Neil Thompson agreed to look at feasibility of Dual undulator / 2 FELs in one cavity before 25 May. Then to investigate if coherent undulator radiation could also be used, but significant longer pulse lengths expected to be a problem due to slippage. FMQ noted that George Neil may already have proposed a solution for 2 FEL outputs with one injector system- HO will speak to him.
UV-vis detection pulse would be provided by down converting the UV-FEL radiation. This has the advantage of maintaining high rep rate compared to table top laser system.
MB confirms that can transport FEL light with good efficiency and to provide spot size required.
It was agreed that this experiment would be an ideal system to develop data acquisition for. GRM agreed to initiate a flow diagram for this.
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