neutronpy.instrument.Chopper¶

class neutronpy.instrument.Chopper(distance, speed, width, chopper_type, acceptance, counter_rot=False, radius=None, depth=None, tau=None)[source]¶

Class defining a chopper object for using Time of Flight spectrometer resolution calculations.

Parameters:

distance : float: Distance of the chopper from the source in cm.
speed : float: Speed of the chopper in Hz.
width : float: width of the beam at the chopper in cm.
chopper_type : string: The type of chopper: ‘disk’ or ‘fermi’.
acceptance : float: If chopper_type == ‘disk’, angular acceptance of the chopper in degrees, unless radius is defined, in which case acceptance is the size of the opening in the disk in cm. If chopper_type == ‘fermi’, distance between chopper blades in cm.
counter_rot : bool, optional: If the disk chopper consists of two counter rotating choppers, set to True (Default: False).
radius : float, optional: radius of the chopper in cm. If defined, and chopper_type == ‘disk’, then acceptance is assumed to be in units of cm.
depth : float, optional: The depth of the Fermi Chopper blades, to calculate angular acceptance. Required if chopper_type == ‘fermi’.
tau : float, optional: Custom value of the resolution of the chopper in standard deviation in units of microseconds. Used to override the automatic calculation of tau.

Attributes:

distance
speed
width
chopper_type
acceptance
radius
depth
tau: Calculate the time resolution of the chopper