# SPDX-License-Identifier: BSD-3-Clause
# Copyright (c) 2025 Scipp contributors (https://github.com/scipp)
from types import MappingProxyType
import scipp as sc
from scippneutron.chopper import DiskChopper
# Choppers
Hz = sc.Unit("Hz")
deg = sc.Unit("deg")
meter = sc.Unit("m")
parameters = {
"WFMC_1": {
"frequency": 56.0,
"phase": 93.244,
"distance": 6.85,
"open": [-1.9419, 49.5756, 98.9315, 146.2165, 191.5176, 234.9179],
"close": [1.9419, 55.7157, 107.2332, 156.5891, 203.8741, 249.1752],
},
"WFMC_2": {
"frequency": 56.0,
"phase": 97.128,
"distance": 7.15,
"open": [-1.9419, 51.8318, 103.3493, 152.7052, 199.9903, 245.2914],
"close": [1.9419, 57.9719, 111.6510, 163.0778, 212.3468, 259.5486],
},
"FOC_1": {
"frequency": 42.0,
"phase": 81.303297,
"distance": 8.4,
"open": [-5.1362, 42.5536, 88.2425, 132.0144, 173.9497, 216.7867],
"close": [5.1362, 54.2095, 101.2237, 146.2653, 189.417, 230.7582],
},
"BP_1": {
"frequency": 7.0,
"phase": 31.080,
"distance": 8.45,
"open": [-23.6029],
"close": [23.6029],
},
"FOC_2": {
"frequency": 42.0,
"phase": 107.013442,
"distance": 12.2,
"open": [-16.3227, 53.7401, 120.8633, 185.1701, 246.7787, 307.0165],
"close": [16.3227, 86.8303, 154.3794, 218.7551, 280.7508, 340.3188],
},
"BP_2": {
"frequency": 7.0,
"phase": 44.224,
"distance": 12.25,
"open": [-34.4663],
"close": [34.4663],
},
"T0_alpha": {
"frequency": 14.0,
"phase": 179.672,
"distance": 13.5,
"open": [-167.8986],
"close": [167.8986],
},
"T0_beta": {
"frequency": 14.0,
"phase": 179.672,
"distance": 13.7,
"open": [-167.8986],
"close": [167.8986],
},
"FOC_3": {
"frequency": 28.0,
"phase": 92.993,
"distance": 17.0,
"open": [-20.302, 45.247, 108.0457, 168.2095, 225.8489, 282.2199],
"close": [20.302, 85.357, 147.6824, 207.3927, 264.5977, 319.4024],
},
"FOC_4": {
"frequency": 14.0,
"phase": 61.584,
"distance": 23.69,
"open": [-16.7157, 29.1882, 73.1661, 115.2988, 155.6636, 195.5254],
"close": [16.7157, 61.8217, 105.0352, 146.4355, 186.0987, 224.0978],
},
"FOC_5": {
"frequency": 14.0,
"phase": 82.581,
"distance": 33.0,
"open": [-25.8514, 38.3239, 99.8064, 160.1254, 217.4321, 272.5426],
"close": [25.8514, 88.4621, 147.4729, 204.0245, 257.7603, 313.7139],
},
}
[docs]
def choppers(source_position: sc.Variable) -> MappingProxyType[str, DiskChopper]:
"""
List of ESS ODIN choppers.
We make the choppers information available in this way as loading them directly from
the NeXus files is currently failing due to empty time-series logs.
Parameters
----------
source_position:
Position of the source in the coordinate system of the choppers.
The raw chopper positions are defined relative to the source position.
"""
return MappingProxyType(
{
key: DiskChopper(
frequency=-ch["frequency"] * Hz,
beam_position=sc.scalar(0.0, unit="deg"),
phase=-ch["phase"] * deg,
axle_position=sc.vector(value=[0, 0, ch["distance"]], unit="m")
+ source_position,
slit_begin=sc.array(dims=["cutout"], values=ch["open"], unit="deg"),
slit_end=sc.array(dims=["cutout"], values=ch["close"], unit="deg"),
)
for key, ch in parameters.items()
}
)
