FEL source simulation¶
Introduction¶
Documentation for FEL source simulation can be found on this page.
Data access¶
Data in archive can be exported using web browser. Initial FEL source can be downloaded from here:
with authentication (xfel/desy account)
If you use this dataset, please acknowledge [SALDIN99].
[SALDIN99] |
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Output data description¶
The output data is expected in hdf5 format, and the glossary can be found below. FEL source module is responsible for writing out in the format specified below.
FELsource_out_<7 digit ID>.h5 (Output HDF glossary)¶
Field name | Description | Data type | Units |
---|---|---|---|
data/ | |||
data/arrEhor | Complex EM field written in 4D array, horizontal polarization | Float | |
data/arrEver | Complex EM field written in 4D array, vertical polarization | Float | |
params/ | Parameters for wavefront propagation | ||
params/Mesh/nSlices | Numbers of points vs photon energy/time for the pulse | Int | |
params/Mesh/nx | Numbers of points, horizontal | Int | |
params/Mesh/ny | Numbers of points, vertical | Int | |
params/Mesh/sliceMax | Max value of time [s] or energy [ev] for pulse (fragment) | Float | s or ev |
params/Mesh/sliceMin | Min value of time [s] or energy [ev] for pulse (fragment) | Float | s or ev |
params/Mesh/xMax | Maximum of horizontal range | Float | m |
params/Mesh/xMin | Minimum of horizontal range | Float | m |
params/Mesh/yMax | Maximum of vertical range | Float | m |
params/Mesh/yMin | Minimum of vertical range | Float | m |
params/Mesh/zCoord | Longitudinal position, for FEL output data - length of active undulator | m | |
params/Rx | Instantaneous horizontal wavefront radius | Float | m |
params/Ry | Instantaneous vertical wavefront radius | Float | m |
params/dRx | Error of wavefront horizontal radius | Float | m |
params/dRy | Error of wavefront vertical radius | Float | m |
params/nval | complex electric field nval==2 | Int | |
params/photonEnergy | Average photon energy | Float | ev |
params/wDomain | Wavefront in time or frequency (photon energy) domain | String | |
params/wEFieldUnit | Electric field units, {sqrt(W/mm^2) (time domain), arbitrary} | String | |
params/wFloatType | Electric field numerical type | String | |
params/wSpace | R-space or Q-space wavefront presentation | String | |
params/xCentre | Horizontal transverse coordinates of wavefront instant ‘source center’ | Float | m |
params/yCentre | Vertical transverse coordinates of wavefront instant ‘source center’ | Float | m |
history/parent/info/ | Information about input data | ||
history/parent/info/ contact | Contact Information | String | |
history/parent/info/ data_description | Description of FEL data | String | |
history/parent/info/ method_description | Method description | String | |
history/parent/info/ package_version | Package version | String | |
misc/ | Complimentary information | ||
history/parent/misc/ FAST2XY.DAT | FELsource_params_FAST2XY.txt used for post-processing FAST output | String | |
history/parent/misc/ angular_distribution | radial distribution of far field divergence | Float | |
history/parent/misc/ spot_size | near field transverse FEL beam size (FWHM) | Float | |
history/parent/misc/ gain_curve | gain curve, dependence of FEL pulse energy (column 2) from number of working point (column 0) and active undulator length z[cm] (column 1) | Float | |
history/parent/misc/nzc | number of working point defines active undulator length | Int | |
history/parent/misc/ temporal_struct | FEL pulse temporal structure, instantaneous power P(tau) | Float | |
version | hdf5 format version | Float | 0.1 |
Diagnostic (diagnostic_felsrc.py)¶
Fig.1. Pulse irradiance XY map (number of photons per pixel), the title contains size of the pixel;
Fig.2. Pulse time structure, the title contains the pulse energy value.