MERLIN

Merlin is a high-count-rate, medium-energy-resolution, direct-geometry spectrometer at the ISIS Neutron and Muon Source. [1]

References

Versions

MERLIN

For details on the parameters associated with the MERLIN version, please see the MERLIN data.

Models

PyChop_fit

This is the recommended PyChop_fit model - it is an alias for the PyChop_fit_v1 model, which is the model actually containing the data.

Important

PyChop_fit refers to the best version of this model - using a specific version may run the risk using a model with known bugs or other issues and is not advisable unless replicating the results of a given version of the model.

PyChop_fit_v1

This section contains the data for the MERLIN instrument associated with the PyChop_fit_v1 model. For more information about how the model works and its implementation, please see resins.models.pychop.PyChopModelFermi. For more information on the model parameters, please see PyChop_fit_v1 model data.

Configurations:

Data

name: "MERLIN"
default_version: "MERLIN"
version:
    MERLIN:
        default_model: "PyChop_fit"
        models:
            PyChop_fit: "PyChop_fit_v1"
            PyChop_fit_v1:
                function: "pychop_fit_fermi"
                citation: ['R. I. Bewley, R. A. Ewings, M. D. Le, T. G. Perring and D. J. Voneshen, 2018. PyChop', 'https://mantidproject.github.io/docs-versioned/v6.10.0/interfaces/direct/PyChop.html']
                parameters:
                    d_chopper_sample: 1.925
                    d_sample_detector: 2.5
                    aperture_width: 0.06667
                    theta: 26.7
                    defaults:
                        e_init: 400
                        chopper_frequency: 400
                    frequency_matrix: [[0], [1]]
                    moderator:
                        type: 2
                        scaling_function: None
                        measured_wavelength: [3.81238, 5.38791, 2.20214, 2.69636, 3.25068, 1.70664, 1.9078, 1.4425, 3.11379, 2.41294, 2.47528, 1.27219, 2.07682, 1.05882, 1.55818]
                        measured_width: [49, 56, 34, 37, 42, 29, 30, 25, 40, 34, 35, 21, 31, 18, 26]
                        parameters: [80.0, 0.5226]
                    detector:
                        type: 2
                        phi: 0.0
                        depth: 0.025
                    sample:
                        type: 0
                        thickness: "2e-3"
                        width: 0.04
                        height: 0.04
                        gamma: 0.0
                    choppers:
                        Disk:
                            distance: 9.3
                            nslot: 1
                            slot_width: 950
                            slot_ang_pos: None
                            guide_width: 64
                            radius: 250
                            num_disk: 1
                            is_phase_independent: True
                            default_phase: 1500
                        Fermi:
                            distance: 9.995
                            aperture_distance: 7.19
                configurations:
                    chopper_package:
                        default_option: "G"
                        G:
                            pslit: 0.0002
                            radius: 0.005
                            rho: 1000
                            tjit: 0.0
                            restrictions: {'chopper_frequency': [50, 601, 50], 'e_init': [0, 181]}
                        S:
                            pslit: 0.00228
                            radius: 0.049
                            rho: 1.3
                            tjit: 0.0
                            restrictions: {'chopper_frequency': [50, 601, 50], 'e_init': [7, 2000]}