Keywords for Arguments

In several functions of spectra-ui, a number of arguments should be given to specify the calculation conditions and parameters. The details of each function are given below.

Select the Calculation Type

Before starting any calculation in spectra-ui, the calculation type should be selected by calling "SelectCalculation()" function, using a number of keywords summarized below as its arguments.

Arguments available in the function SelectCalculation to specify the calculation type.

Category

Menu Items

Arguments

Numerical Scheme

Far Field & Ideal Condition

far

Near Field

near

Coherent Radiation

cohrad

Characterization at the Source Point

srcpoint

Coherent Mode Decomposition

CMD

Wavefront Propagation

propagate

Fixed Point Calculation

fixed

Method

Energy Dependence

energy

Spatial Dependence

spatial

K Dependence

Kvalue

Time Dependence

temporal

Wigner Function

wigner

Main Target Item

Angular Flux Density

fdensa

Partial Flux

pflux

Total Flux

tflux

Angular Power Density

pdensa

Partial Power

ppower

Resolved Power Density

pdensr

Spatial Flux Density

fdenss

Spatial Power Density

pdenss

Surface Power Density

spdens

Volume Power Density

vpdens

CMD with the Wigner Function

CMD2d

Modal Profile

CMDPP

Check Validity

CMDcheck

Electric Field

efield

Complex Amplitude

camp

Phase-Space Distribution

phasespace

Spatial Profile

sprof

Condition

Rectangular Slit

slitrect

Circular Slit

slitcirc

Along Axis

along

Mesh: x-y

meshxy

Mesh: r-φ

meshrphi

Simplified Calculation

simpcalc

Flux at a Fixed Energy

fluxfix

Peak Flux Curve

fluxpeak

Power

powercv

Planar Surface: x-z

xzplane

Planar Surface: y-z

yzplane

Cylindrical Surface

pipe

X-X' (Sliced)

XXpslice

X-X' (Projected)

XXpprj

Y-Y' (Sliced)

YYpslice

Y-Y' (Projected)

YYpprj

X-X'-Y-Y'

XXpYYp

Sub-Condition

Target Harmonics

tgtharm

All Harmonics

allharm

Sliced

Wslice

Projected on X-X'

WprjX

Projected on Y-Y'

WprjY

Related Characteristics

Wrel

Main Input Parameters

After selecting the calculation type, parameters to specify the accelerator, light source, and numerical conditions may need to be modified, which can be done by calling "Set()" function with adequate arguments. For example,

spectra.Set("acc", "eGeV", 3)

means that the electron energy is set to 3 GeV. Refer to the followings for details.

Parameter category (1st argument)

The 1st argument should specify the category of the parameter to be set. It should be given by one of the keywords as summarized below.

Arguments available in the function Set to set a parameter.

Arguments

Remarks

acc

Parameters to specify the accelerator as shown in Accelerator subpanel.

src

Parameters to specify the light source as shown in Light Source subpanel.

config

Configurations to specify the numerical conditions as shown in Configurations subpanel.

outfile

Configurations to specify the output file as shown in Output File subpanel.

Accelerator parameters

Keywords to specify the accelerator parameters are summarized below. They should be used as the 2nd agument. Refer to Accelerator for more details about each parameter.

Keywords available in the 2nd argument (arg2) of Set("acc", arg2, arg3) to change the parameters and options of Accelerator.

Notation in GUI

Argument

Detail

Format

Type

type

Type of the accelerator. In SPECTRA, the accelerators are categorized into two types: Storage Ring and Linear Accelerator.

string - one of below:
'Storage Ring'
'Linear Accelerator'

Energy (GeV)

eGeV

Total energy of the electron beam.

float

Current (mA)

imA

Average beam current of the accelerator. The former is determined by the user, while the latter is evaluated from Pulses/sec and Bunch Charge.

float

Bunches

bunches

Number of electron bunches stored in the storage ring.

int

Pulses/sec

pulsepps

Number of electron bunches/second in the linear accelerator.

int

σz (mm)

bunchlength

Bunch length and charge of the electron beam.

float

Bunch Charge (nC)

bunchcharge

float

Nat. Emittance (m.rad)

emitt

Natural emittance of the electron beam.

float

Coupling Constant

coupl

Coupling constant and energy spread of the electron beam.

float

Energy Spread

espread

float

βx,y (m)

beta

Twiss parameters at the center of the light source

list

αx,y

alpha

list

ηx,y (m)

eta

Dispersion functions and their derivatives.

list

η'x,y

etap

list

Bunch Profile

bunchtype

Specify the distribution functions of the electron beam in the spatial and temporal domains.

string - one of below:
'Gaussian'
'Current Profile'
'E-t Profile'
'Particle Distribution'

Current Profile

currdata

Dictionary data to represent the current profile of the electron bunch.

dictionary

E-t Profile

Etdata

Dictionary data to represent the electron distribution in the E-t phase space.

dictionary

Injection Condition

injectionebm

Specify the injection condition, or the position and angle of the electron beam at the entrance of the light source.

string - one of below:
'Automatic'
'Align at Entrance'
'Align at Center'
'Align at Exit'
'Custom'

x,y (mm)

xy

Horizontal/vertical positions/angles at the entrance. Available when Injection Condition is Custom

list

x',y' (mrad)

xyp

list

Zero Emittance

zeroemitt

Calculation is done without the effects due to the finite emittance and/or energy spread of the electron beam.

bool

Zero Energy Spread

zerosprd

bool

Single Electron

singlee

SR emitted by a single electron is supposed.

bool

Additional R56 (m)

R56add

Strength of the virtual dispersive section located in front of the light source. Effective for computation of coherent radiation, if E-t Profile is chosen for the electron bunch profile.

float

Light source parameters

Keywords to specify the light source parameters are summarized below. They should be used as the 2nd agument. Refer to Light Source for more details about each parameter.

Keywords available in the 2nd argument (arg2) of Set("src", arg2, arg3) to change the parameters and options of Light Source.

Notation in GUI

Argument

Detail

Format

Type

type

Type of the light source

string - one of below:
'Linear Undulator'
'Vertical Undulator'
'Helical Undulator'
'Elliptic Undulator'
'Figure-8 Undulator'
'Vertical Figure-8 Undulator'
'Multi-Harmonic Undulator'
'Bending Magnet'
'Wiggler'
'EMPW'
'Wavelength Shifter'
'Field Mapping'
'Periodic: User Defined'
'User Defined'

Field Profile

fvsz

Dictionary data to represent the whole magnetic field distribution of the light source.

dictionary

Field Profile (1 Period)

fvsz1per

Dictionary data to represent the magnetic field distribution of the light source over a single period.

dictionary

Gap (mm)

gap

Gap of the ID.

float

Bx,y (T)

bxy

Field amplitude (IDs) or uniform field (BMs).

list

B (T)

b

float

Main Field (T)

bmain

Peak fields of the main and sub poles of Wavelength Shifters.

float

Sub Field (T)

subpoleb

float

λu (mm)

lu

Magnetic Period Length of the ID

float

Device Length (m)

devlength

Total length of the ID

float

# of Reg. Periods

periods

Number of regular periods.

float

K0x,0y

Kxy0

Available for APPLE undulators. Maximum K values (deflection parameters) when the phase is adjusted to generate horizontal and vertical polarizations.

list

Phase Shift (mm)

phase

Longitudinal shift of each magnetic array for the APPLE undulators, defined as the displacement from the position for the horizontally-polarized mode. To be specific, K values are given as $K_x=K_{x0}sin(2\pi\Delta z/\lambda_u)$ and $K_y=K_{y0}cos(2\pi\Delta z/\lambda_u)$, where $\Delta z$ is the phase shift.

float

Kx,y

Kxy

K values of the ID.

list

K value

K

float

ε1st (eV)

e1st

Fundamental photon energy and wavelength of undulator radiation.

float

λ1st (nm)

lambda1

float

Harmonic Component

multiharm

Arrange the harmonic components for Multi-Harmonic Undulators.

dictionary

ρ (m)

radius

Radius of the BM.

float

BM Length (m)

bendlength

Specify the geometric configuration of BMs. Origin for CSR defines the longitudinal coordinate where the electron bunch length or the temporal profile is defined to calculate coherent radiation.

float

BM Fringe Length (m)

fringelen

float

Main Length (m)

mplength

Lengths of the main and sub poles of the Wavelength Shifter.

float

Sub Length (m)

subpolel

float

BM Interval (m)

bminterv

Distance between two BMs.

float

Origin for CSR (m)

csrorg

Specify the geometric configuration of BMs. Origin for CSR defines the longitudinal coordinate where the electron bunch length or the temporal profile is defined to calculate coherent radiation.

float

Gap-Field Relation

gaplink

Specify the relation between the gap and peak field of the ID.

string - one of below:
'None'
'Automatic'
'Import Table'

Br (T)

br

Remanent field of the permanent magnet.

float

Geometrical Factor (x,y)

geofactor

Geometrical factor to reduce the peak magnetic field (x,y).

list

Gap vs. Field

gaptbl

dictionary

APPLE Configuration

apple

Enable/disable the APPLE configuration for Elliptic Undulators.

bool

Field Structure

field_str

Specify the field-distribution symmetry of the ID.

string - one of below:
'Antisymmetric'
'Symmetric'

End Correction Magnet

endmag

Put additional magnets at the both ends, for orbit compensation.

bool

Natural Focusing

natfocus

Apply the natural focusing of IDs.

string - one of below:
'None'
'Bx'
'By'
'Both'

Field Offset & Taper

fielderr

Specify if the magnetic field contains an error component.

bool

Offset x,y (T)

boffset

Magnetic field offset, such as that coming from the ambient field.

list

Lin. Taper x,y (/m)

ltaper

Linear (a1) and quadratic (a2) taper coefficients. The magnetic field amplitude is given as \[B(z)=B_0(1+a_1z+a_2z^2),\] where $B_0$ is the field amplitude corresponding to the K value.

list

Quad. Taper x,y (/m2)

qtaper

list

Add Phase Error

phaseerr

If ticked, the RMS phase error and relevant parameters can be specified.

bool

Random Number Seed

seed

Seed for the random number generator to model the field error.

int

σB (%)

fsigma

RMS of the peak field variation.

float

σφ (deg.)

psigma

RMS of the phase error.

float

σx,y (mm);

xysigma

RMS of the trajectory error.

list

Tandem Arrangement

bmtandem

Calculate radiation from two BMs located at the both ends of the straight section.

bool

Segmentation

segment_type

Arrange the segmented undulator configuration.

string - one of below:
'None'
'Identical'
'2nd: Swap Bx,y'
'2nd: Flip Bx'
'2nd: Flip By'

Number of Segments

segments

Number of undulator segments (M) if Identical is selected for Segmentation, or number of segment pair (M') for other options.

int

Half Number of Segments

hsegments

int

Segment Interval (m)

interval

Distance between the center positions of adjacent undulator segments.

float

Δφ (π)

phi0

Additional phase in the unit of π.

float

Δφ1,2 (π)

phi12

Additional phase in the unit of π: subscripts 1 and 2 refer to the odd and even drift sections

list

Matching Distance (m)

mdist

Distance between virtual focusing magnets in the matching section to arrange the periodic lattice function.

float

Periodic β Function

perlattice

The betatron function is periodic with the period of segment interval.

bool

Configurations

Keywords to specify the numerical configurations are summarized below. They should be used as the 2nd agument. Refer to Configurations for more details about each parameter.

Keywords available in the 2nd argument (arg2) of Set("config", arg2, arg3) to change the parameters and options of Configurations.

Notation in GUI

Argument

Detail

Format

Type

type

str

Distance from the Source (m)

slit_dist

Distance from the center of the light source to the observation point.

float

Auto Config. for Energy Range

autoe

Enable automatic configuration to define the energy range and pitch.

bool

Harmonic Range

hrange

Harmonic range or target harmonic number for K-value dependence calculations.

list

Target Harmonic

hfix

int

Maximum Harmonic

hmax

Maximum harmonic number to be considered.

int

Detuning

detune

Photon energy defined as a detuned value, i.e., $\varepsilon/(n\varepsilon_1)-1$, where $n$ is the target harmonic number.

float

Energy Range (eV)

erange

Energy range and pitch for Energy Dependence calculations.

list

Energy Pitch (eV)

de

float

Energy Pitch for Integration (eV)

epitch

Energy pitch for integration in Volume Power Density calculations. Needs to be defined by the user for User Defined light sources.

float

Points (Energy)

emesh

Number of energy points for Energy Dependence calculations.

int

Normalized Energy

nefix

Same as the above, but normalized by ε1st.

float

Target Energy (eV)

efix

Photon energy to be fixed.

float

Position x,y (mm)

xyfix

Transverse position/angle at the observation point.

list

Angle θx,y (mrad)

qxyfix

list

Surface Pos. x (mm)

spdxfix

Position of the object and range of observation for Spatial Power Density calculations.

float

Surface Pos. y (mm)

spdyfix

float

Surface Radius (mm)

spdrfix

float

Θ (deg.)

Qnorm

Normal vectors to specify the inner surface of the object irradiated by SR.

float

Φ (deg.)

Phinorm

float

Glancing Angle (deg.)

Qgl

Angular acceptance to confine the photon beam and resultant illuminated area of the object, and angles to define the condition of glancing incidence for Volume Power Density calculations.Azimuth of Incidence define the direction along which the object is inclined: if it is vertically tilted as in the case of a crystal monochromator, this parameter should be 90 degree, as shown in the above figure.

float

Azimuth of Incidence (deg.)

Phiinc

float

Slit Pos.: x,y (mm)

slitpos

Specify the configuration of the slit positions and aperture.

list

Slit Pos.: θx,y (mrad)

qslitpos

list

Δ/Σs: x,y

nslitapt

list

Δx,Δy (mm)

slitapt

list

Δθx,y (mrad)

qslitapt

Angular acceptance to confine the photon beam and resultant illuminated area of the object, and angles to define the condition of glancing incidence for Volume Power Density calculations.Azimuth of Incidence define the direction along which the object is inclined: if it is vertically tilted as in the case of a crystal monochromator, this parameter should be 90 degree, as shown in the above figure.

list

Slit r1,2 (mm)

slitr

Specify the configuration of the slit positions and aperture.

list

Slit θ1,2 (mrad)

slitq

list

Power Upper Limit (kW)

pplimit

Upper limit of the partial power to define the width and height of the rectangular slit for K Dependence calculations.

float

z range (m)

zrange

Position of the object and range of observation for Spatial Power Density calculations.

list

Points (z)

zmesh

Number of observation points in the relevant range

int

Auto Config. for Transverse Range

autot

Enable automatic configuration to define the spatial/angular range and grid intervals.

bool

Transverse Grid

gridspec

Specify the transverse grid at each longitudinal step.

string - one of below:
'Automatic'
'Normalized'
'Fixed'

Finer Spatial Grid

grlevel

Specify a finer grid interval if Automaticis selected for Transverse Grid. Default is 0 and a larger number means a finer interval.

int

x Range (mm)

xrange

Position of the object and range of observation for Spatial Power Density calculations.

list

θx Range (mrad)

qxrange

Range of the Observation positions/angles for Spatial Dependence calculations: (a) [Along Axis] and [Mesh: x-y] and (b) [Mesh: r-φ].

list

x Range/Σ

wnxrange

list

Points (x)

xmesh

Number of observation points in the relevant range

int

δx Range (mm)

wdxrange

list

δx Range/Σ

wndxrange

list

Points (δx)

wdxmesh

float

y Range (mm)

yrange

Position of the object and range of observation for Spatial Power Density calculations.

list

θy Range (mrad)

qyrange

Range of the Observation positions/angles for Spatial Dependence calculations: (a) [Along Axis] and [Mesh: x-y] and (b) [Mesh: r-φ].

list

y Range/Σ

wnyrange

list

Points (y)

ymesh

Number of observation points in the relevant range

int

δy Range (mm)

wdyrange

list

δy Range/Σ

wndyrange

list

Points (δy)

wdymesh

float

r Range (mm)

rrange

Range of the Observation positions/angles for Spatial Dependence calculations: (a) [Along Axis] and [Mesh: x-y] and (b) [Mesh: r-φ].

list

θ Range (mrad)

qrange

list

Points (r)

rphimesh

Number of observation point in the relevant range.

int

Points (θ)

qphimesh

int

φ Range (deg.)

phirange

Range of the Observation positions/angles for Spatial Dependence calculations: (a) [Along Axis] and [Mesh: x-y] and (b) [Mesh: r-φ].

list

Points (φ)

phimesh

Number of observation point in the relevant range.

int

Depth Range (mm)

drange

Depth range and number of points for Volume Power Density calculations.

list

Points (Depth)

dmesh

int

Optical Element

optics

Specify an optical element inserted in the beamline.

string - one of below:
'None'
'Single Slit'
'Double Slit'
'Ideal Thin Lens'

Position (m)

optpos

Longitudinal position to insert an optical element.

float

Aperture x (mm)

aptx

Horizontal aperture size.

float

Slit Distance x (mm)

aptdistx

Distance between the double slit in the horizontal direction.

float

Aperture y (mm)

apty

Vertical aperture size.

float

Slit Distance y (mm)

aptdisty

Distance between the double slit in the vertical direction.

float

Soft Edge Fringe Size (mm)

softedge

Range of the Soft Edgeof the slit. At the edge of the slit, the photon intensity is supposed to gradually drop, as opposed to a hard-edged condition. Longer soft-edge ranges reduce the diffraction effects. In addition, the memory requirement is relaxed as well.

float

Limit of Diffraction Effect

diflim

Specify the threshold to cut off the diffraction effects and determine the angular range to compute the Wigner function after passing through a slit.

float

Larger Angular Range

anglelevel

Specify the angular range to evaluate the Wigner function after an optical element. If set to 0, the angular range is determined to be consistent with the relevant parameters; a larger number means a large angular range.

int

Focal Length x (m)

foclenx

Focal length of an ideal lens in the horizontal direction.

float

Focal Length y (m)

focleny

Focal length of an ideal lens in the vertical direction.

float

Angular Profile

aprofile

Export the angular profile after an optical element.

bool

Wigner Function

wigner

Export the Wigner function after an optical element.

bool

Cross Spectral Density

csd

Export the cross spectral density.

bool

Degree of Coherence

degcoh

Export the degree of spatial coherence.

bool

K Range

krange

Range of the K values and number of points.

list

K Range

ckrange

list

Points (K)

kmesh

int

Temporal Range (fs)

trange

Temporal range and number of points for Time Dependence calculations.

list

Points (Temporal)

tmesh

int

γΔθx,y

gtacc

Angular acceptance normalized by γ-1 to calculate the Wigner function.

list

X' Acceptance (mrad)

horizacc

float

Slice X (mm)

Xfix

Transverse positions and angles at the source point where the Wigner function is calculated.

float

Slice Y (mm)

Yfix

float

Slice X' (mrad)

Xpfix

float

Slice Y' (mrad)

Ypfix

float

X Range (mm)

Xrange

Calculation range/number of points of the transverse positions/angles at the source point.

list

Points (X)

Xmesh

int

X' Range (mrad)

Xprange

list

Points (X')

Xpmesh

int

Y Range (mm)

Yrange

list

Points (Y)

Ymesh

int

Y' Range (mrad)

Yprange

list

Points (Y')

Ypmesh

int

Filtering

filter

Specify the type of filtering.

string - one of below:
'None'
'Generic Filter'
'BPF: Gaussian'
'BPF: Boxcar'
'Custom'

Filters

fmateri

Dictionaly data to represent the filter materials.

dictionary

Custom Filter

fcustom

Dictionaly data to represent the filter transmission rate.

dictionary

Central Energy (eV)

bpfcenter

Central photon energy of the bandpath filter (BPF).

float

Width (eV)

bpfwidth

Full width of the boxcar-type BPF.

float

Width (σ, eV)

bpfsigma

1σ of the Gaussian BPF.

float

Max. Trans. Rate

bpfmaxeff

Maximum transmission rate of the BPF.

float

Absorbers

amateri

dictionary

Depth Step

dstep

Specify how to change the energy/depth position in the calculation range.

string - one of below:
'Linear'
'Logarithmic'
'Export at Arbitrary Positions'

Depth-Position Data

depthdata

Dictionaly data to represent the depth positions.

dictionary

Define Obs. Point in

defobs

Specify how to represent the transverse observation points.

string - one of below:
'Position'
'Angle'

Normalize Photon Energy

normenergy

Specify the photon energy as a normalized value.

bool

Energy Step

estep

Specify how to change the energy/depth position in the calculation range.

string - one of below:
'Linear'
'Logarithmic'

Slit Aperture Size

aperture

Specify how to represent the width and height of the rectangular slit.

string - one of below:
'Fixed'
'Normalized'

Set Upper Limit on Power

powlimit

Put an upper limit on the allowable partial power.

bool

Optimize ΔX' for Computation

optDx

Horizontal angular acceptance is virtually closed to reduce the computation time, without changing the calculation results.

bool

Level of Smoothing Along X

xsmooth

Apply smoothing for the Wigner function of BMs and wigglers; larger values results in more smooth profiles.

float

Observation in the Fourier Plane

fouriep

Calculation is done at the Fourier Plane as schematically illustrated below, to evaluate the angular profile at the source point (center of the light source)

bool

Wiggler Approximation

wiggapprox

Apply the wiggler approximation, in which radiation incoherently summed up (as photons).

bool

Spectral Smoothing

esmooth

Apply the spectral smoothing; this is useful to reduce the computation time by smoothing the spectral fine structure potentially found in undulator radiation.

bool

Smoothing Window (%)

smoothwin

Smoothing window in %; this means that the photon flux at 1000 eV is given as the average from 995 to 1005 eV.

float

Accuracy Level

acclevel

float

Accuracy

accuracy

Specify the numerical accuracy. In most cases, Default is recommended, in which case SPECTRA automatically arranges all the relevant parameters.

string - one of below:
'Default'
'Custom'

Perform CMD?

CMD

Perform Coherent Mode Decomposition after calculating the Wigner function.

bool

Apply GS Model

GSModel

Use Gaussian-Schell (GS) model to simplify the CMD and reduce computation time.

bool

GS Model X/Y

GSModelXY

Use Gaussian-Schell (GS) model for CMD. Select the axis to apply.

string - one of below:
'None'
'X'
'Y'
'Both'

Export Field Profile

CMDfld

Calculate and export the modal profiles based on the CMD results

string - one of below:
'None'
'JSON'
'BINARY'
'Both'

Export Intensity Profile

CMDint

Calculate and export the modal intensity profiles based on the CMD results

bool

Range: X,Y (mm)

fieldrangexy

Range of the spatial grid to export the modal profile.

list

Range: X (mm)

fieldrangex

float

Range: Y (mm)

fieldrangey

float

Step: X,Y (mm)

fieldgridxy

Intervals of the spatial grid points to export the modal profile.

list

Step: X (mm)

fieldgridx

float

Step: Y (mm)

fieldgridy

float

HG Order Limit (X,Y)

HGorderxy

Upper limit of the order of the Hermite-Gaussian functions to be used in the CMD.

list

HG Order Limit (X)

HGorderx

float

HG Order Limit (Y)

HGordery

float

Max. HG Order (X,Y)

maxHGorderxy

Maximum orders of the coherent mode.

list

Max. HG Order (X)

maxHGorderx

float

Max. HG Order (Y)

maxHGordery

float

Maximum CMD Order

maxmode

Maximum number of the coherent modes for post-processing (exporting the modal profile, reconstructing the Wigner functions).

float

Flux Cutoff

fcutoff

Cutoff flux (normalized) to be used to determine the maximum HG order of of each coherent mode.

float

Amplitude Cutoff

cutoff

Cutoff amplitude (normalized) of individual modes, below which Hermite-Gaussian functions are neglected.

float

Compare Wigner Function

CMDcmp

Reconstruct the Wigner function using the CMD result to check its validity.

bool

Compare Intensity Profile

CMDcmpint

Reconstruct the flux density profile using the CMD result to check its validity.

bool

FEL Mode

fel

Coherent radiation in an FEL (free electron laser) mode is calculated. If this option is enabled, interaction (energy exchange) between electrons and radiation is taken into account in solving the equation of electron motion in the 6D phase space.

string - one of below:
'None'
'Prebunched FEL'
'Seeded FEL'
'Seeded with Chirped Pulse'
'Seeded with Double Pulse'
'Seeded width Custom Pulse'
'Reuse Bunch Factor'

Seed Spectrum

seedspec

dictionary

Pulse Energy (mJ)

pulseE

Seed pulse energy.

float

Wavelength (nm)

wavelen

Seed wavelength.

float

Pulse Length (FWHM, fs)

pulselen

Seed pulse length.

float

TL. Pulse Length (FWHM, fs)

tlpulselen

Transform-limited pulse length of the chirped seed pulse.

float

Source Size (FWHM, mm)

srcsize

Seed source size.

float

Waist Position (m)

waistpos

Longitudinal position where the seed pulse forms a beam waist.

float

Timing (fs)

timing

Relative time of the seed pulse with respect to the electron beam.

float

GDD (fs2)

gdd

Group delay dispersion and third order dispersion of the chirped seed pulse.

float

TOD (fs3)

tod

float

Pulse Energy: 1,2 (mJ)

pulseE_d

Pulse energies of the 1st and 2nd seed pulses. Available when Seeded with Double Pulse is chosen. Note that there are a number of parameters having the same suffix (1,2), which denotes that they are for the 1st and 2nd seed pulses.

list

Wavelength: 1,2 (nm)

wavelen_d

list

TL. Pulse Length: 1,2 (FWHM, fs)

tlpulselen_d

list

Source Size: 1,2 (FWHM, mm)

srcsize_d

list

Waist Position: 1,2 (m)

waistpos_d

list

Timing: 1,2 (fs)

timing_d

list

GDD: 1,2 (fs2)

gdd_d

list

TOD: 1,2 (fs3)

tod_d

list

Step: Initial, Interval (m)

svstep

Define the longitudinal step to solve the FEL equation.

list

Substeps for Radiation

radstep

float

Photon Energy ROI (eV)

eproi

Photon energy range of interest to solve the FEL equation.

list

Number of Particles

particles

Number of macro-particles to represent the electron beam.

float

e- Energy Interval

edevstep

Interval of the electron energy deviation to export the electron density in the (E-t) phase space.

float

R56 (m)

R56

Strength of the virtual dispersive section. Need to be specified if option is enabled.

float

Export Intermediate Data

exportInt

Export the intermediate data evaluated during the process of solving the FEL equation.

bool

Bunch with Dispersion

R56Bunch

Export the bunch profile after the electron beam passes through a virtual dispersive section located downstream of the source, as in the high-gain harmonic generation (HGHG) FELs.

bool

E-t Data

exportEt

Export the electron density in the (E-t) phase space.

bool

Output File Settings

Keywords to specify the output file are summarized below. They should be used as the 2nd agument. Refer to Output File Subpanel for more details about each parameter.

Keywords available in the 2nd argument (arg2) of Set("outfile", arg2, arg3) to change the parameters and options of Output File.

Notation in GUI

Argument

Detail

Format

Format

format

Select the format of the output file from three options.

string - one of below:
'JSON'
'ASCII'
'Both'

Folder

folder

Input the path of the output file in [Folder], a prefix text in [Prefix], and a serial number in [Serial Number]. Then the output file name is given as [Folder]/[Prefix]-[Serial Number].[Format]

str: path to the directory

Prefix

prefix

str

Comment

comment

Input any comment in [Comment] if necessary, which is saved in the output file and can be referred later on.

str

Serial Number

serial

Input the path of the output file in [Folder], a prefix text in [Prefix], and a serial number in [Serial Number]. Then the output file name is given as [Folder]/[Prefix]-[Serial Number].[Format]

int

Other parameters

Numerical accuracy

The numerial accuracy is specified by calling "SetAccuracy()". The 1st argument specifies the numerical procedure (integration, discretization, etc.), and should be one of the followings.

Arguments available in SetAccuracy().

Category

Menu Items

Arguments

Integration/Discretization Step

Longitudinal Step

accdisctra

Transverse Grid

accinobs

Electron Energy Step

accineE

Photon Energy Step

accinpE

Integration Range

Longitudinal Range

acclimtra

Transverse Range

acclimobs

Photon Energy Range

acclimpE

Electron Energy Range

acclimeE

Others

Harmonic Convergence

accconvharm

Energy Consistency

accEcorr

Monte Carlo Integral Tolerance

accconvMC

Coherent Radiation Integral Tolerance

accconvMCcoh

Limit Macroparticles

acclimMCpart

Maximum Macroparticles

accMCpart

Unit for data import

To import the data prepared by the user, its unit should be specified by calling "SetUnit()". The 1st argment specifies the data type and should be one of the followings.

Arguments available in PreProcess.SetUnit()

Menu Items

Arguments

Options

Gap

gap

mm, m, cm

Longitudinal Position (z)

zpos

Magnetic Field (Bx,y)

magf

Tesla, Gauss

Depth for Volume Power Density

depth

mm, m, cm

Time for Bunch Profile

time

mm, m, fs, s, ps