Name

Unit

Description

Default

ttmin

deg

Minimum horizontal analyzer coverage angle (option 1)

NAN

ttmax

deg

analyzer coverage angle in horizontal xz-plane between -180 and 180

NAN

tt0

deg

Horizontal angular center of the analyzer coverage (option 2)

NAN

ttwidth

deg

horizontal coverage as center and full width

NAN

width

m

absolute width

NAN

phimin

deg

Minimum vertical analyzer coverage angle (option 1)

NAN

phimax

deg

vertical analyzer coverage between -90 and 90 (-180 and 180 if debyescherrer==1) option 2

NAN

phi0

deg

Vertical angular center of the analyzer coverage (option 2)

NAN

phiwidth

deg

vertical coverage as center and full width option 3

NAN

height

m

absolute height (only if debyescherrer==0)

NAN

debyescherrer

-180...180

(0/1) bend analyzer following a Debye-Scherrer ring along scattering angle tt (twotheta) (phi =

0

facette

m

width of square crystal facettes arranged on the spherical surface (set 0 to disable). Default: 0 Warning: Facettation will fail at the poles along +-y axis.

0

facette_xi

deg

random misalignemt of each facette. Default: 0

0

centerfocus

0/1

Component origin is the center of the analyzer sphere if 1, if set to 0 the origin is on the analyzer surface. Default: 0

0

radius

m

Radius of curvature, set to 0 for a flat surface. Default: 0

0

tau

A\(^{-1}\)

Scattering vector of the reflex (sometimes also called Q...)

NAN

lambda

A

Alternatively to tau: backscattered wavelength

NAN

R0

Peak reflectivity. Default: 1

1.0

dtauovertau

1

Plateau width of the Ewald/Darwin curve (see

NAN

dtauovertau_ext

Relative variation of tau (randomized for each trajectory, full width)

0

ewald

0/1

Use Ewald curve if 1, Darwin curve if 0. Default: 1 (Ewald)

1

sigma

meV

Width of the Gaussian reflectivity curve in meV (corresponding to the energy resolution). (The width will be transformed and the Gaussian is actually calculated in k-space.)

NAN

ismirror

0/1

Simply reflect all neutrons if 1. Good for debugging/visualization. Default: 0

0

speed

m/s

Maximum Doppler speed. The actual monochromator velocity is randomized between -speed and +speed. Default: 0

0

amplitude

m

Amplitude of the Doppler movement. Default: 0

0

smartphase

0/1

Optimize Doppler phase for better MC efficiency if set to 1. *WARNING:* Experimental option! Always compare to a simulation without smartphase. Better do not use smartwidth with Ewald/Darwin curves due to their endless tails. Default: 0

0

smartwidth

meV

Half width of the possible energy reflection window for smartphase. Default: 5*sigma OR 10*2*dtauovertau*E0

NAN

exclusive

0/1

If set to 1, absorb all neutrons that missed the monochromator/analyzer surface. Default: 0

0

transmit

0...1

Monte-Carlo probability of transmitting an event through the monochromator/analyzer surface. (Events with R=1.0 for DarwinE/Ewald curves are always reflected!). Default: 0

0

verbose

1

If non-zero, print additional information

0