From dcab70123501465d66df62de4e9822a03d7f61b5 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Wed, 25 Feb 2026 21:12:55 +0100
Subject: [PATCH 01/10] start removing tof from powder dream workflow

---
 src/ess/dream/workflows.py   | 16 +++----
 src/ess/powder/conversion.py | 89 +++++++++++++++++-------------------
 src/ess/powder/types.py      | 25 +++++-----
 3 files changed, 60 insertions(+), 70 deletions(-)

diff --git a/src/ess/dream/workflows.py b/src/ess/dream/workflows.py
index 5b629172..0f1ec112 100644
--- a/src/ess/dream/workflows.py
+++ b/src/ess/dream/workflows.py
@@ -7,9 +7,9 @@
 import sciline
 import scipp as sc
 import scippnexus as snx
+from ess.reduce.kinematics import GenericWavelengthWorkflow
 from ess.reduce.nexus.types import DetectorBankSizes, NeXusName
 from ess.reduce.parameter import parameter_mappers
-from ess.reduce.time_of_flight import GenericTofWorkflow
 from ess.reduce.workflow import register_workflow
 from scippneutron.metadata import Software
 
@@ -23,12 +23,12 @@
     CaveMonitorPosition,  # Should this be a DREAM-only parameter?
     EmptyCanRun,
     KeepEvents,
+    LookupTableFilename,
     LookupTableRelativeErrorThreshold,
     PixelMaskFilename,
     Position,
     ReducerSoftware,
     SampleRun,
-    TimeOfFlightLookupTableFilename,
     TofMask,
     TwoThetaMask,
     VanadiumRun,
@@ -73,7 +73,7 @@
 
 def _get_lookup_table_filename_from_configuration(
     configuration: InstrumentConfiguration,
-) -> TimeOfFlightLookupTableFilename:
+) -> LookupTableFilename:
     from .data import tof_lookup_table_high_flux
 
     match configuration:
@@ -84,13 +84,13 @@ def _get_lookup_table_filename_from_configuration(
         case InstrumentConfiguration.high_resolution:
             raise NotImplementedError("High resolution configuration not yet supported")
 
-    return TimeOfFlightLookupTableFilename(out)
+    return LookupTableFilename(out)
 
 
 def _collect_reducer_software() -> ReducerSoftware:
     return ReducerSoftware(
         [
-            Software.from_package_metadata('essdiffraction'),
+            # Software.from_package_metadata('essdiffraction'),
             Software.from_package_metadata('scippneutron'),
             Software.from_package_metadata('scipp'),
         ]
@@ -100,7 +100,7 @@ def _collect_reducer_software() -> ReducerSoftware:
 def DreamWorkflow(**kwargs) -> sciline.Pipeline:
     """
     Dream generic workflow with default parameters.
-    The workflow is based on the GenericTofWorkflow.
+    The workflow is based on the GenericWavelengthWorkflow.
     It can load data from a NeXus file recorded on the DREAM instrument, and can
     compute time-of-flight for the neutron events.
 
@@ -111,9 +111,9 @@ def DreamWorkflow(**kwargs) -> sciline.Pipeline:
     ----------
     kwargs:
         Additional keyword arguments are forwarded to the base
-        :func:`GenericTofWorkflow`.
+        :func:`GenericWavelengthWorkflow`.
     """
-    wf = GenericTofWorkflow(
+    wf = GenericWavelengthWorkflow(
         run_types=[SampleRun, VanadiumRun, EmptyCanRun],
         monitor_types=[BunkerMonitor, CaveMonitor],
         **kwargs,
diff --git a/src/ess/powder/conversion.py b/src/ess/powder/conversion.py
index 42f21743..fb27a726 100644
--- a/src/ess/powder/conversion.py
+++ b/src/ess/powder/conversion.py
@@ -14,6 +14,8 @@
 from .types import (
     CalibrationData,
     CorrectedDetector,
+    DspacingDetector,
+    DspacingMonitor,
     ElasticCoordTransformGraph,
     EmptyCanSubtractedIntensityTof,
     EmptyCanSubtractedIofDspacing,
@@ -25,8 +27,8 @@
     Position,
     RunType,
     SampleRun,
-    TofDetector,
-    TofMonitor,
+    # TofDetector,
+    # TofMonitor,
     WavelengthDetector,
     WavelengthMonitor,
 )
@@ -98,31 +100,21 @@ def _consume_positions(position, sample_position, source_position):
 def to_dspacing_with_calibration(
     data: sc.DataArray,
     calibration: sc.Dataset,
+    graph: dict,
 ) -> sc.DataArray:
     """
     Transform coordinates to d-spacing from calibration parameters.
-
-    Computes d-spacing from time-of-flight stored in `data`.
-
-    Attention
-    ---------
-    `data` may have a wavelength coordinate and dimension,
-    but those are discarded.
-    Only the stored time-of-flight is used, that is, any modifications to
-    the wavelength coordinate after it was computed from time-of-flight are lost.
-
-    Raises
-    ------
-    KeyError
-        If `data` does not contain a 'tof' coordinate.
+    Computes d-spacing from wavelength stored in `data`.
 
     Parameters
     ----------
     data:
-        Input data in tof or wavelength dimension.
-        Must have a tof coordinate.
+        Input data in wavelength dimension.
+        Must have a wavelength coordinate.
     calibration:
         Calibration data.
+    graph:
+        Graph for the coordinate transformation, used to restore tof from wavelength.
 
     Returns
     -------
@@ -134,9 +126,10 @@ def to_dspacing_with_calibration(
     ess.powder.conversions.dspacing_from_diff_calibration
     """
     out = merge_calibration(into=data, calibration=calibration)
-    out = _restore_tof_if_in_wavelength(out)
+    # Restore tof from wavelength
+    out = out.transform_coords("tof", graph=graph, keep_intermediate=False)
 
-    graph = {"dspacing": _dspacing_from_diff_calibration}
+    pos_graph = {"dspacing": _dspacing_from_diff_calibration}
     # `_dspacing_from_diff_calibration` does not need positions but conceptually,
     # the conversion maps from positions to d-spacing.
     # The mechanism with `_tag_positions_consumed` is meant to ensure that,
@@ -145,10 +138,10 @@ def to_dspacing_with_calibration(
     if "position" in out.coords or (
         out.bins is not None and "position" in out.bins.coords
     ):
-        graph["_tag_positions_consumed"] = _consume_positions
+        pos_graph["_tag_positions_consumed"] = _consume_positions
     else:
-        graph["_tag_positions_consumed"] = lambda: sc.scalar(0)
-    out = out.transform_coords("dspacing", graph=graph, keep_intermediate=False)
+        pos_graph["_tag_positions_consumed"] = lambda: sc.scalar(0)
+    out = out.transform_coords("dspacing", graph=pos_graph, keep_intermediate=False)
     out.coords.pop("_tag_positions_consumed", None)
     return CorrectedDetector[RunType](out)
 
@@ -178,7 +171,7 @@ def powder_coordinate_transformation_graph(
     return ElasticCoordTransformGraph(
         {
             **scn.conversion.graph.beamline.beamline(scatter=True),
-            **scn.conversion.graph.tof.elastic("tof"),
+            **scn.conversion.graph.tof.elastic("kinematics"),
             'source_position': lambda: source_position,
             'sample_position': lambda: sample_position,
             'gravity': lambda: gravity,
@@ -186,27 +179,27 @@ def powder_coordinate_transformation_graph(
     )
 
 
-def _restore_tof_if_in_wavelength(data: sc.DataArray) -> sc.DataArray:
-    out = data.copy(deep=False)
-    outer = out.coords.get("wavelength", None)
-    if out.bins is not None:
-        binned = out.bins.coords.get("wavelength", None)
-    else:
-        binned = None
+# def _restore_tof_from_wavelength(data: sc.DataArray) -> sc.DataArray:
+#     out = data.copy(deep=False)
+#     outer = out.coords.get("wavelength", None)
+#     if out.bins is not None:
+#         binned = out.bins.coords.get("wavelength", None)
+#     else:
+#         binned = None
 
-    if outer is not None or binned is not None:
-        get_logger().info("Discarded coordinate 'wavelength' in favor of 'tof'.")
+#     if outer is not None or binned is not None:
+#         get_logger().info("Discarded coordinate 'wavelength' in favor of 'tof'.")
 
-    if "wavelength" in out.dims:
-        out = out.rename_dims(wavelength="tof")
-    return out
+#     if "wavelength" in out.dims:
+#         out = out.rename_dims(wavelength="tof")
+#     return out
 
 
 def add_scattering_coordinates_from_positions(
-    data: TofDetector[RunType],
+    data: WavelengthDetector[RunType],
     graph: ElasticCoordTransformGraph[RunType],
     calibration: CalibrationData,
-) -> WavelengthDetector[RunType]:
+) -> DspacingDetector[RunType]:
     """
     Add ``wavelength``, ``two_theta`` and ``dspacing`` coordinates to the data.
     The input ``data`` must have a ``tof`` coordinate, as well as the necessary
@@ -226,7 +219,7 @@ def add_scattering_coordinates_from_positions(
         keep_intermediate=False,
     )
     out = convert_to_dspacing(out, graph, calibration)
-    return WavelengthDetector[RunType](out)
+    return DspacingDetector[RunType](out)
 
 
 def convert_to_dspacing(
@@ -237,7 +230,7 @@ def convert_to_dspacing(
     if calibration is None:
         out = data.transform_coords(["dspacing"], graph=graph, keep_intermediate=False)
     else:
-        out = to_dspacing_with_calibration(data, calibration=calibration)
+        out = to_dspacing_with_calibration(data, calibration=calibration, graph=graph)
         for key in ("wavelength", "two_theta"):
             if key in out.coords.keys():
                 out.coords.set_aligned(key, False)
@@ -301,20 +294,20 @@ def powder_monitor_coordinate_transformation_graph(
     )
 
 
-def convert_monitor_to_wavelength(
-    monitor: TofMonitor[RunType, MonitorType],
-    graph: MonitorCoordTransformGraph[RunType],
-) -> WavelengthMonitor[RunType, MonitorType]:
-    return WavelengthMonitor[RunType, MonitorType](
-        monitor.transform_coords("wavelength", graph=graph, keep_intermediate=False)
-    )
+# def convert_monitor_to_wavelength(
+#     monitor: TofMonitor[RunType, MonitorType],
+#     graph: MonitorCoordTransformGraph[RunType],
+# ) -> WavelengthMonitor[RunType, MonitorType]:
+#     return WavelengthMonitor[RunType, MonitorType](
+#         monitor.transform_coords("wavelength", graph=graph, keep_intermediate=False)
+#     )
 
 
 providers = (
     add_scattering_coordinates_from_positions,
     convert_reduced_to_tof,
     convert_reduced_to_empty_can_subtracted_tof,
-    convert_monitor_to_wavelength,
+    # convert_monitor_to_wavelength,
     powder_coordinate_transformation_graph,
     powder_monitor_coordinate_transformation_graph,
 )
diff --git a/src/ess/powder/types.py b/src/ess/powder/types.py
index db5b8065..d53fe588 100644
--- a/src/ess/powder/types.py
+++ b/src/ess/powder/types.py
@@ -14,12 +14,11 @@
 
 import sciline
 import scipp as sc
-from scippneutron.io import cif
-from scippneutron.metadata import Person, Software
-
+from ess.reduce.kinematics import types as kin_t
 from ess.reduce.nexus import types as reduce_t
-from ess.reduce.time_of_flight import types as tof_t
 from ess.reduce.uncertainty import UncertaintyBroadcastMode as _UncertaintyBroadcastMode
+from scippneutron.io import cif
+from scippneutron.metadata import Person, Software
 
 EmptyDetector = reduce_t.EmptyDetector
 EmptyMonitor = reduce_t.EmptyMonitor
@@ -36,12 +35,12 @@
 
 DetectorBankSizes = reduce_t.DetectorBankSizes
 
-TofDetector = tof_t.TofDetector
-TofMonitor = tof_t.TofMonitor
-PulseStrideOffset = tof_t.PulseStrideOffset
-TimeOfFlightLookupTable = tof_t.TimeOfFlightLookupTable
-TimeOfFlightLookupTableFilename = tof_t.TimeOfFlightLookupTableFilename
-LookupTableRelativeErrorThreshold = tof_t.LookupTableRelativeErrorThreshold
+WavelengthDetector = kin_t.WavelengthDetector
+WavelengthMonitor = kin_t.WavelengthMonitor
+PulseStrideOffset = kin_t.PulseStrideOffset
+LookupTable = kin_t.LookupTable
+LookupTableFilename = kin_t.LookupTableFilename
+LookupTableRelativeErrorThreshold = kin_t.LookupTableRelativeErrorThreshold
 
 SampleRun = reduce_t.SampleRun
 VanadiumRun = reduce_t.VanadiumRun
@@ -95,7 +94,7 @@ def __init__(self, *args: Any, **kwargs: Any) -> None:
 """Detector calibration data."""
 
 
-class WavelengthDetector(sciline.Scope[RunType, sc.DataArray], sc.DataArray):
+class DspacingDetector(sciline.Scope[RunType, sc.DataArray], sc.DataArray):
     """Data with scattering coordinates computed for all events: wavelength, 2theta,
     d-spacing."""
 
@@ -170,9 +169,7 @@ class MonitorFilename(sciline.Scope[RunType, Path], Path):
     """
 
 
-class WavelengthMonitor(
-    sciline.Scope[RunType, MonitorType, sc.DataArray], sc.DataArray
-):
+class DspacingMonitor(sciline.Scope[RunType, MonitorType, sc.DataArray], sc.DataArray):
     """Monitor histogram in wavelength."""
 
 

From 82aebc5b8272c10d3e2f9c0eaf4d786a9d5dacbc Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Thu, 26 Feb 2026 08:46:51 +0100
Subject: [PATCH 02/10] update notebooks

---
 .../dream-advanced-powder-reduction.ipynb     | 14 ++++-
 .../dream/dream-make-tof-lookup-table.ipynb   | 38 +++++++------
 .../dream/dream-powder-reduction.ipynb        | 53 +++++++++++++------
 3 files changed, 73 insertions(+), 32 deletions(-)

diff --git a/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb b/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb
index bb3ca987..cb98646e 100644
--- a/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb
+++ b/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb
@@ -65,6 +65,7 @@
     "workflow[CaveMonitorPosition] = sc.vector([0.0, 0.0, -4220.0], unit=\"mm\")\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
+    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
     "workflow[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
@@ -186,6 +187,7 @@
     "workflow[CaveMonitorPosition] = sc.vector([0.0, 0.0, -4220.0], unit=\"mm\")\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
+    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
     "workflow[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
@@ -261,6 +263,7 @@
     "workflow[CalibrationFilename] = None\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
+    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
     "workflow[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
@@ -375,6 +378,7 @@
     "workflow[CalibrationFilename] = None\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
+    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
     "workflow[UncertaintyBroadcastMode] = UncertaintyBroadcastMode.drop\n",
     "# Edges for binning in d-spacing:\n",
@@ -610,6 +614,14 @@
     "    vmin=1e-3,\n",
     ")"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "dd340637-933f-4c73-b996-285b7394bd03",
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {
@@ -628,7 +640,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.14"
+   "version": "3.12.12"
   }
  },
  "nbformat": 4,
diff --git a/docs/user-guide/dream/dream-make-tof-lookup-table.ipynb b/docs/user-guide/dream/dream-make-tof-lookup-table.ipynb
index 3a1515d8..8edefb6b 100644
--- a/docs/user-guide/dream/dream-make-tof-lookup-table.ipynb
+++ b/docs/user-guide/dream/dream-make-tof-lookup-table.ipynb
@@ -5,9 +5,9 @@
    "id": "0",
    "metadata": {},
    "source": [
-    "# Create a time-of-flight lookup table for DREAM\n",
+    "# Create a wavelength lookup table for DREAM\n",
     "\n",
-    "This notebook shows how to create a time-of-flight lookup table for the DREAM instrument."
+    "This notebook shows how to create a wavelength lookup table for the DREAM instrument."
    ]
   },
   {
@@ -18,7 +18,7 @@
    "outputs": [],
    "source": [
     "import scipp as sc\n",
-    "from ess.reduce import time_of_flight\n",
+    "from ess.reduce import kinematics as kin\n",
     "from ess.reduce.nexus.types import AnyRun\n",
     "from ess.dream.beamline import InstrumentConfiguration, choppers"
    ]
@@ -60,17 +60,17 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "wf = time_of_flight.TofLookupTableWorkflow()\n",
+    "wf = kin.LookupTableWorkflow()\n",
     "\n",
-    "wf[time_of_flight.LtotalRange] = sc.scalar(5.0, unit=\"m\"), sc.scalar(80.0, unit=\"m\")\n",
-    "wf[time_of_flight.NumberOfSimulatedNeutrons] = 200_000  # Increase this number for more reliable results\n",
-    "wf[time_of_flight.SourcePosition] = sc.vector([0, 0, 0], unit='m')\n",
-    "wf[time_of_flight.DiskChoppers[AnyRun]] = disk_choppers\n",
-    "wf[time_of_flight.DistanceResolution] = sc.scalar(0.1, unit=\"m\")\n",
-    "wf[time_of_flight.TimeResolution] = sc.scalar(250.0, unit='us')\n",
-    "wf[time_of_flight.PulsePeriod] = 1.0 / sc.scalar(14.0, unit=\"Hz\")\n",
-    "wf[time_of_flight.PulseStride] = 1\n",
-    "wf[time_of_flight.PulseStrideOffset] = None"
+    "wf[kin.LtotalRange] = sc.scalar(5.0, unit=\"m\"), sc.scalar(80.0, unit=\"m\")\n",
+    "wf[kin.NumberOfSimulatedNeutrons] = 5_000_000  # Increase this number for more reliable results\n",
+    "wf[kin.SourcePosition] = sc.vector([0, 0, 0], unit='m')\n",
+    "wf[kin.DiskChoppers[AnyRun]] = disk_choppers\n",
+    "wf[kin.DistanceResolution] = sc.scalar(0.1, unit=\"m\")\n",
+    "wf[kin.TimeResolution] = sc.scalar(250.0, unit='us')\n",
+    "wf[kin.PulsePeriod] = 1.0 / sc.scalar(14.0, unit=\"Hz\")\n",
+    "wf[kin.PulseStride] = 1\n",
+    "wf[kin.PulseStrideOffset] = None"
    ]
   },
   {
@@ -88,7 +88,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "table = wf.compute(time_of_flight.TimeOfFlightLookupTable)\n",
+    "table = wf.compute(kin.LookupTable)\n",
     "table.array"
    ]
   },
@@ -117,8 +117,16 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "table.save_hdf5('DREAM-high-flux-tof-lut-5m-80m.h5')"
+    "table.save_hdf5('DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5')"
    ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "a43b15e7-a225-4e73-b037-78f01dbefcf7",
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {
diff --git a/docs/user-guide/dream/dream-powder-reduction.ipynb b/docs/user-guide/dream/dream-powder-reduction.ipynb
index b067bca1..18c65f51 100644
--- a/docs/user-guide/dream/dream-powder-reduction.ipynb
+++ b/docs/user-guide/dream/dream-powder-reduction.ipynb
@@ -56,7 +56,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "workflow = dream.DreamGeant4Workflow(\n",
+    "wf = dream.DreamGeant4Workflow(\n",
     "    run_norm=powder.RunNormalization.monitor_histogram,\n",
     ")"
    ]
@@ -77,26 +77,27 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "workflow[Filename[SampleRun]] = dream.data.simulated_diamond_sample()\n",
-    "workflow[Filename[VanadiumRun]] = dream.data.simulated_vanadium_sample()\n",
-    "workflow[Filename[EmptyCanRun]] = dream.data.simulated_empty_can()\n",
-    "workflow[CalibrationFilename] = None\n",
+    "wf[Filename[SampleRun]] = dream.data.simulated_diamond_sample()\n",
+    "wf[Filename[VanadiumRun]] = dream.data.simulated_vanadium_sample()\n",
+    "wf[Filename[EmptyCanRun]] = dream.data.simulated_empty_can()\n",
+    "wf[CalibrationFilename] = None\n",
     "\n",
-    "workflow[MonitorFilename[SampleRun]] = dream.data.simulated_monitor_diamond_sample()\n",
-    "workflow[MonitorFilename[VanadiumRun]] = dream.data.simulated_monitor_vanadium_sample()\n",
-    "workflow[MonitorFilename[EmptyCanRun]] = dream.data.simulated_monitor_empty_can()\n",
-    "workflow[CaveMonitorPosition] = sc.vector([0.0, 0.0, -4220.0], unit=\"mm\")\n",
+    "wf[MonitorFilename[SampleRun]] = dream.data.simulated_monitor_diamond_sample()\n",
+    "wf[MonitorFilename[VanadiumRun]] = dream.data.simulated_monitor_vanadium_sample()\n",
+    "wf[MonitorFilename[EmptyCanRun]] = dream.data.simulated_monitor_empty_can()\n",
+    "wf[CaveMonitorPosition] = sc.vector([0.0, 0.0, -4220.0], unit=\"mm\")\n",
     "\n",
-    "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
+    "wf[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
+    "wf[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
-    "workflow[NeXusDetectorName] = \"mantle\"\n",
+    "wf[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
-    "workflow[UncertaintyBroadcastMode] = UncertaintyBroadcastMode.drop\n",
+    "wf[UncertaintyBroadcastMode] = UncertaintyBroadcastMode.drop\n",
     "# Edges for binning in d-spacing:\n",
-    "workflow[DspacingBins] = sc.linspace(\"dspacing\", 0.3, 2.3434, 201, unit=\"angstrom\")\n",
+    "wf[DspacingBins] = sc.linspace(\"dspacing\", 0.3, 2.3434, 201, unit=\"angstrom\")\n",
     "\n",
     "# Do not mask any pixels / voxels:\n",
-    "workflow = powder.with_pixel_mask_filenames(workflow, [])"
+    "wf = powder.with_pixel_mask_filenames(wf, [])"
    ]
   },
   {
@@ -114,6 +115,26 @@
     "If we didn't want to subtract an empty can measurement from the sample measurement, we would instead request `IofDspacing[SampleRun]` and `ReducedTofCIF`."
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "5c212c16-08dc-4582-891c-7938b2cc75bd",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "wf.compute(LookupTableRelativeErrorThreshold)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "40e1be11-41f0-4839-9efa-e3e1de650808",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "wf.visualize(ReducedEmptyCanSubtractedTofCIF, graph_attr={\"rankdir\": \"LR\"})"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -121,7 +142,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "results = workflow.compute([\n",
+    "results = wf.compute([\n",
     "    EmptyCanSubtractedIofDspacing,\n",
     "    ReducedEmptyCanSubtractedTofCIF\n",
     "])\n",
@@ -229,7 +250,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.11.10"
+   "version": "3.12.12"
   }
  },
  "nbformat": 4,

From edb1ad983fd1adbcf80002fccf39ce12a5bd29d0 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 13 Mar 2026 15:39:09 +0100
Subject: [PATCH 03/10] updates for latest version of workflow

---
 src/ess/dream/workflows.py   |  8 ++++----
 src/ess/powder/conversion.py |  4 ++--
 src/ess/powder/types.py      | 14 +++++++-------
 3 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/src/ess/dream/workflows.py b/src/ess/dream/workflows.py
index c5984e26..7d344535 100644
--- a/src/ess/dream/workflows.py
+++ b/src/ess/dream/workflows.py
@@ -6,9 +6,9 @@
 import sciline
 import scipp as sc
 import scippnexus as snx
-from ess.reduce.kinematics import GenericWavelengthWorkflow
 from ess.reduce.nexus.types import DetectorBankSizes, NeXusName
 from ess.reduce.parameter import parameter_mappers
+from ess.reduce.unwrap import GenericUnwrapWorkflow
 from ess.reduce.workflow import register_workflow
 from scippneutron.metadata import Software
 
@@ -99,7 +99,7 @@ def _collect_reducer_software() -> ReducerSoftware:
 def DreamWorkflow(**kwargs) -> sciline.Pipeline:
     """
     Dream generic workflow with default parameters.
-    The workflow is based on the GenericWavelengthWorkflow.
+    The workflow is based on the GenericUnwrapWorkflow.
     It can load data from a NeXus file recorded on the DREAM instrument, and can
     compute time-of-flight for the neutron events.
 
@@ -110,9 +110,9 @@ def DreamWorkflow(**kwargs) -> sciline.Pipeline:
     ----------
     kwargs:
         Additional keyword arguments are forwarded to the base
-        :func:`GenericWavelengthWorkflow`.
+        :func:`GenericUnwrapWorkflow`.
     """
-    wf = GenericWavelengthWorkflow(
+    wf = GenericUnwrapWorkflow(
         run_types=[SampleRun, VanadiumRun, EmptyCanRun],
         monitor_types=[BunkerMonitor, CaveMonitor],
         **kwargs,
diff --git a/src/ess/powder/conversion.py b/src/ess/powder/conversion.py
index b647c5cb..6008b42c 100644
--- a/src/ess/powder/conversion.py
+++ b/src/ess/powder/conversion.py
@@ -171,7 +171,7 @@ def powder_coordinate_transformation_graph(
     return ElasticCoordTransformGraph(
         {
             **scn.conversion.graph.beamline.beamline(scatter=True),
-            **scn.conversion.graph.kinematics.elastic("wavelength"),
+            **scn.conversion.graph.tof.elastic("wavelength"),
             'source_position': lambda: source_position,
             'sample_position': lambda: sample_position,
             'gravity': lambda: gravity,
@@ -286,7 +286,7 @@ def powder_monitor_coordinate_transformation_graph(
     return MonitorCoordTransformGraph(
         {
             **scn.conversion.graph.beamline.beamline(scatter=False),
-            **scn.conversion.graph.kinematics.elastic("wavelength"),
+            **scn.conversion.graph.tof.elastic("wavelength"),
             'source_position': lambda: source_position,
             'sample_position': lambda: sample_position,
             'gravity': lambda: gravity,
diff --git a/src/ess/powder/types.py b/src/ess/powder/types.py
index d53fe588..65d12b2e 100644
--- a/src/ess/powder/types.py
+++ b/src/ess/powder/types.py
@@ -14,9 +14,9 @@
 
 import sciline
 import scipp as sc
-from ess.reduce.kinematics import types as kin_t
 from ess.reduce.nexus import types as reduce_t
 from ess.reduce.uncertainty import UncertaintyBroadcastMode as _UncertaintyBroadcastMode
+from ess.reduce.unwrap import types as unwrap_t
 from scippneutron.io import cif
 from scippneutron.metadata import Person, Software
 
@@ -35,12 +35,12 @@
 
 DetectorBankSizes = reduce_t.DetectorBankSizes
 
-WavelengthDetector = kin_t.WavelengthDetector
-WavelengthMonitor = kin_t.WavelengthMonitor
-PulseStrideOffset = kin_t.PulseStrideOffset
-LookupTable = kin_t.LookupTable
-LookupTableFilename = kin_t.LookupTableFilename
-LookupTableRelativeErrorThreshold = kin_t.LookupTableRelativeErrorThreshold
+WavelengthDetector = unwrap_t.WavelengthDetector
+WavelengthMonitor = unwrap_t.WavelengthMonitor
+PulseStrideOffset = unwrap_t.PulseStrideOffset
+LookupTable = unwrap_t.LookupTable
+LookupTableFilename = unwrap_t.LookupTableFilename
+LookupTableRelativeErrorThreshold = unwrap_t.LookupTableRelativeErrorThreshold
 
 SampleRun = reduce_t.SampleRun
 VanadiumRun = reduce_t.VanadiumRun

From b18d2666eec374a0c0f18a20b4d6b8f3d4f774c8 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 20 Mar 2026 14:21:18 +0100
Subject: [PATCH 04/10] add new wavelength tables to data registry and update
 advanced notebook

---
 .../dream-advanced-powder-reduction.ipynb     | 12 -------
 src/ess/dream/data.py                         | 36 +++++++++++++++++++
 src/ess/dream/workflows.py                    |  6 ++--
 3 files changed, 39 insertions(+), 15 deletions(-)

diff --git a/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb b/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb
index cb98646e..f02589fe 100644
--- a/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb
+++ b/docs/user-guide/dream/dream-advanced-powder-reduction.ipynb
@@ -65,7 +65,6 @@
     "workflow[CaveMonitorPosition] = sc.vector([0.0, 0.0, -4220.0], unit=\"mm\")\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
-    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
     "workflow[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
@@ -187,7 +186,6 @@
     "workflow[CaveMonitorPosition] = sc.vector([0.0, 0.0, -4220.0], unit=\"mm\")\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
-    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
     "workflow[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
@@ -263,7 +261,6 @@
     "workflow[CalibrationFilename] = None\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
-    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
     "workflow[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
@@ -378,7 +375,6 @@
     "workflow[CalibrationFilename] = None\n",
     "\n",
     "workflow[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
-    "workflow[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
     "workflow[UncertaintyBroadcastMode] = UncertaintyBroadcastMode.drop\n",
     "# Edges for binning in d-spacing:\n",
@@ -614,14 +610,6 @@
     "    vmin=1e-3,\n",
     ")"
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "dd340637-933f-4c73-b996-285b7394bd03",
-   "metadata": {},
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {
diff --git a/src/ess/dream/data.py b/src/ess/dream/data.py
index 1e8136eb..33f43908 100644
--- a/src/ess/dream/data.py
+++ b/src/ess/dream/data.py
@@ -40,6 +40,9 @@
         # `shrink_nexus.py` script in the `tools` folder at the top level of the
         # `essdiffraction` repository.
         "TEST_DREAM_nexus_sorted-2023-12-07.nxs": "md5:599b426a93c46a7b4b09a874bf288c53",  # noqa: E501
+        # Wavelength lookup tables
+        "DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5": "md5:10c80c9de311cfa246f7b2c165eb0b49",  # noqa: E501
+        "DREAM-high-flux-wavelength-lut-5m-80m-bc240.h5": "md5:9741176f8da9b34c2a15967a43e21462",  # noqa: E501
     },
 )
 
@@ -293,3 +296,36 @@ def tof_lookup_table_high_flux(bc: Literal[215, 240] = 215) -> Path:
             return get_path("DREAM-high-flux-tof-lut-5m-80m-bc240.h5")
         case _:
             raise ValueError(f"Unsupported band-control chopper (BC) value: {bc}")
+
+
+def lookup_table_high_flux(bc: Literal[215, 240] = 215) -> Path:
+    """Path to a HDF5 file containing a wavelength lookup table for high-flux mode.
+
+    The table was created using the ``tof`` package and the chopper settings for the
+    DREAM instrument in high-resolution mode.
+    Can return tables for two different band-control chopper (BC) settings:
+    - ``bc=215``: corresponds to the settings of the choppers in the tutorial data.
+    - ``bc=240``: a setting with less time overlap between frames.
+
+    Note that the phase of the band-control chopper (BCC) was set to 215 degrees in the
+    Geant4 simulation which generated the data used in the documentation notebooks.
+    This has since been found to be non-optimal as it leads to time overlap between the
+    two frames, and a value of 240 degrees is now recommended.
+
+    This table was computed using `Create a wavelength lookup table for DREAM
+    <../../user-guide/dream/dream-make-wavelength-lookup-table.rst>`_
+    with ``NumberOfSimulatedNeutrons = 5_000_000``.
+
+    Parameters
+    ----------
+    bc:
+        Band-control chopper (BC) setting. The default is 215, which corresponds to the
+        settings of the choppers in the tutorial data.
+    """
+    match bc:
+        case 215:
+            return get_path("DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5")
+        case 240:
+            return get_path("DREAM-high-flux-wavelength-lut-5m-80m-bc240.h5")
+        case _:
+            raise ValueError(f"Unsupported band-control chopper (BC) value: {bc}")
diff --git a/src/ess/dream/workflows.py b/src/ess/dream/workflows.py
index 7d344535..e8124fdb 100644
--- a/src/ess/dream/workflows.py
+++ b/src/ess/dream/workflows.py
@@ -73,13 +73,13 @@
 def _get_lookup_table_filename_from_configuration(
     configuration: InstrumentConfiguration,
 ) -> LookupTableFilename:
-    from .data import tof_lookup_table_high_flux
+    from .data import lookup_table_high_flux
 
     match configuration:
         case InstrumentConfiguration.high_flux_BC215:
-            out = tof_lookup_table_high_flux(bc=215)
+            out = lookup_table_high_flux(bc=215)
         case InstrumentConfiguration.high_flux_BC240:
-            out = tof_lookup_table_high_flux(bc=240)
+            out = lookup_table_high_flux(bc=240)
         case InstrumentConfiguration.high_resolution:
             raise NotImplementedError("High resolution configuration not yet supported")
 

From 7cb2f461c1b62af472c5a3bd43cbc3e10cd81313 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 20 Mar 2026 14:23:28 +0100
Subject: [PATCH 05/10] replace notebook to generate lookup table

---
 ... dream-make-wavelength-lookup-table.ipynb} | 36 ++++++++-----------
 1 file changed, 14 insertions(+), 22 deletions(-)
 rename docs/user-guide/dream/{dream-make-tof-lookup-table.ipynb => dream-make-wavelength-lookup-table.ipynb} (71%)

diff --git a/docs/user-guide/dream/dream-make-tof-lookup-table.ipynb b/docs/user-guide/dream/dream-make-wavelength-lookup-table.ipynb
similarity index 71%
rename from docs/user-guide/dream/dream-make-tof-lookup-table.ipynb
rename to docs/user-guide/dream/dream-make-wavelength-lookup-table.ipynb
index 8edefb6b..05047add 100644
--- a/docs/user-guide/dream/dream-make-tof-lookup-table.ipynb
+++ b/docs/user-guide/dream/dream-make-wavelength-lookup-table.ipynb
@@ -18,7 +18,7 @@
    "outputs": [],
    "source": [
     "import scipp as sc\n",
-    "from ess.reduce import kinematics as kin\n",
+    "from ess.reduce import unwrap\n",
     "from ess.reduce.nexus.types import AnyRun\n",
     "from ess.dream.beamline import InstrumentConfiguration, choppers"
    ]
@@ -40,7 +40,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "disk_choppers = choppers(InstrumentConfiguration.high_flux_BC215)"
+    "disk_choppers = choppers(InstrumentConfiguration.high_flux_BC240)"
    ]
   },
   {
@@ -60,17 +60,17 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "wf = kin.LookupTableWorkflow()\n",
+    "wf = unwrap.LookupTableWorkflow()\n",
     "\n",
-    "wf[kin.LtotalRange] = sc.scalar(5.0, unit=\"m\"), sc.scalar(80.0, unit=\"m\")\n",
-    "wf[kin.NumberOfSimulatedNeutrons] = 5_000_000  # Increase this number for more reliable results\n",
-    "wf[kin.SourcePosition] = sc.vector([0, 0, 0], unit='m')\n",
-    "wf[kin.DiskChoppers[AnyRun]] = disk_choppers\n",
-    "wf[kin.DistanceResolution] = sc.scalar(0.1, unit=\"m\")\n",
-    "wf[kin.TimeResolution] = sc.scalar(250.0, unit='us')\n",
-    "wf[kin.PulsePeriod] = 1.0 / sc.scalar(14.0, unit=\"Hz\")\n",
-    "wf[kin.PulseStride] = 1\n",
-    "wf[kin.PulseStrideOffset] = None"
+    "wf[unwrap.LtotalRange] = sc.scalar(5.0, unit=\"m\"), sc.scalar(80.0, unit=\"m\")\n",
+    "wf[unwrap.NumberOfSimulatedNeutrons] = 200_000  # Increase this number for more reliable results\n",
+    "wf[unwrap.SourcePosition] = sc.vector([0, 0, 0], unit='m')\n",
+    "wf[unwrap.DiskChoppers[AnyRun]] = disk_choppers\n",
+    "wf[unwrap.DistanceResolution] = sc.scalar(0.1, unit=\"m\")\n",
+    "wf[unwrap.TimeResolution] = sc.scalar(250.0, unit='us')\n",
+    "wf[unwrap.PulsePeriod] = 1.0 / sc.scalar(14.0, unit=\"Hz\")\n",
+    "wf[unwrap.PulseStride] = 1\n",
+    "wf[unwrap.PulseStrideOffset] = None"
    ]
   },
   {
@@ -88,7 +88,7 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "table = wf.compute(kin.LookupTable)\n",
+    "table = wf.compute(unwrap.LookupTable)\n",
     "table.array"
    ]
   },
@@ -117,16 +117,8 @@
    "metadata": {},
    "outputs": [],
    "source": [
-    "table.save_hdf5('DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5')"
+    "table.save_hdf5('DREAM-high-flux-wavelength-lut-5m-80m-bc240.h5')"
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "a43b15e7-a225-4e73-b037-78f01dbefcf7",
-   "metadata": {},
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {

From 5533122b48abc4c5884ca498b52fab7ed9aab0e0 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 20 Mar 2026 14:25:57 +0100
Subject: [PATCH 06/10] cleanup simple powder notebook

---
 .../dream/dream-powder-reduction.ipynb        | 25 +------------------
 1 file changed, 1 insertion(+), 24 deletions(-)

diff --git a/docs/user-guide/dream/dream-powder-reduction.ipynb b/docs/user-guide/dream/dream-powder-reduction.ipynb
index 18c65f51..5a3425f9 100644
--- a/docs/user-guide/dream/dream-powder-reduction.ipynb
+++ b/docs/user-guide/dream/dream-powder-reduction.ipynb
@@ -88,7 +88,6 @@
     "wf[CaveMonitorPosition] = sc.vector([0.0, 0.0, -4220.0], unit=\"mm\")\n",
     "\n",
     "wf[dream.InstrumentConfiguration] = dream.InstrumentConfiguration.high_flux_BC215\n",
-    "wf[LookupTableFilename] = \"DREAM-high-flux-wavelength-lut-5m-80m-bc215.h5\"\n",
     "# Select a detector bank:\n",
     "wf[NeXusDetectorName] = \"mantle\"\n",
     "# We drop uncertainties where they would otherwise lead to correlations:\n",
@@ -115,26 +114,6 @@
     "If we didn't want to subtract an empty can measurement from the sample measurement, we would instead request `IofDspacing[SampleRun]` and `ReducedTofCIF`."
    ]
   },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "5c212c16-08dc-4582-891c-7938b2cc75bd",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "wf.compute(LookupTableRelativeErrorThreshold)"
-   ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "40e1be11-41f0-4839-9efa-e3e1de650808",
-   "metadata": {},
-   "outputs": [],
-   "source": [
-    "wf.visualize(ReducedEmptyCanSubtractedTofCIF, graph_attr={\"rankdir\": \"LR\"})"
-   ]
-  },
   {
    "cell_type": "code",
    "execution_count": null,
@@ -166,9 +145,7 @@
    "outputs": [],
    "source": [
     "histogram = intensity.hist()\n",
-    "fig = histogram.plot(title=intensity.coords['detector'].value.capitalize())\n",
-    "fig.ax.set_ylabel(f\"I(d) [{histogram.unit}]\")\n",
-    "fig"
+    "histogram.plot(title=intensity.coords['detector'].value.capitalize(), ylabel=f\"I(d) [{histogram.unit}]\")"
    ]
   },
   {

From 2b6da84ca939ba7b42bf246dde3a7ad8c0d4cf3a Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 20 Mar 2026 14:27:56 +0100
Subject: [PATCH 07/10] cleanup conversion file

---
 src/ess/powder/conversion.py | 32 --------------------------------
 1 file changed, 32 deletions(-)

diff --git a/src/ess/powder/conversion.py b/src/ess/powder/conversion.py
index 6008b42c..234e9aed 100644
--- a/src/ess/powder/conversion.py
+++ b/src/ess/powder/conversion.py
@@ -10,12 +10,10 @@
 
 from .calibration import OutputCalibrationData
 from .correction import merge_calibration
-from .logging import get_logger
 from .types import (
     CalibrationData,
     CorrectedDetector,
     DspacingDetector,
-    DspacingMonitor,
     ElasticCoordTransformGraph,
     EmptyCanSubtractedIntensityTof,
     EmptyCanSubtractedIofDspacing,
@@ -23,14 +21,10 @@
     IntensityDspacing,
     IntensityTof,
     MonitorCoordTransformGraph,
-    MonitorType,
     Position,
     RunType,
     SampleRun,
-    # TofDetector,
-    # TofMonitor,
     WavelengthDetector,
-    WavelengthMonitor,
 )
 
 
@@ -179,22 +173,6 @@ def powder_coordinate_transformation_graph(
     )
 
 
-# def _restore_tof_from_wavelength(data: sc.DataArray) -> sc.DataArray:
-#     out = data.copy(deep=False)
-#     outer = out.coords.get("wavelength", None)
-#     if out.bins is not None:
-#         binned = out.bins.coords.get("wavelength", None)
-#     else:
-#         binned = None
-
-#     if outer is not None or binned is not None:
-#         get_logger().info("Discarded coordinate 'wavelength' in favor of 'tof'.")
-
-#     if "wavelength" in out.dims:
-#         out = out.rename_dims(wavelength="tof")
-#     return out
-
-
 def add_scattering_coordinates_from_positions(
     data: WavelengthDetector[RunType],
     graph: ElasticCoordTransformGraph[RunType],
@@ -294,20 +272,10 @@ def powder_monitor_coordinate_transformation_graph(
     )
 
 
-# def convert_monitor_to_wavelength(
-#     monitor: TofMonitor[RunType, MonitorType],
-#     graph: MonitorCoordTransformGraph[RunType],
-# ) -> WavelengthMonitor[RunType, MonitorType]:
-#     return WavelengthMonitor[RunType, MonitorType](
-#         monitor.transform_coords("wavelength", graph=graph, keep_intermediate=False)
-#     )
-
-
 providers = (
     add_scattering_coordinates_from_positions,
     convert_reduced_to_tof,
     convert_reduced_to_empty_can_subtracted_tof,
-    # convert_monitor_to_wavelength,
     powder_coordinate_transformation_graph,
     powder_monitor_coordinate_transformation_graph,
 )

From 0ab33eb8f2b5c80d1e3cca1b70ca0962c6bd9e35 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 20 Mar 2026 14:47:05 +0100
Subject: [PATCH 08/10] fix types in beer and start fixing calibration to use
 unwrapped eto

---
 src/ess/beer/types.py                |  9 ++++--
 src/ess/powder/conversion.py         | 10 ++++---
 tests/beer/mcstas_reduction_test.py  |  5 ++--
 tests/dream/geant4_reduction_test.py | 41 ++++++++++++++--------------
 4 files changed, 35 insertions(+), 30 deletions(-)

diff --git a/src/ess/beer/types.py b/src/ess/beer/types.py
index c4655bf5..cd29ca54 100644
--- a/src/ess/beer/types.py
+++ b/src/ess/beer/types.py
@@ -12,9 +12,7 @@
 
 import sciline
 import scipp as sc
-
 from ess.reduce.nexus.types import Filename, RawDetector, RunType, SampleRun
-from ess.reduce.time_of_flight.types import TofDetector
 
 
 class StreakClusteredData(sciline.Scope[RunType, sc.DataArray], sc.DataArray):
@@ -24,7 +22,6 @@ class StreakClusteredData(sciline.Scope[RunType, sc.DataArray], sc.DataArray):
 RawDetector = RawDetector
 Filename = Filename
 SampleRun = SampleRun
-TofDetector = TofDetector
 
 
 class DetectorBank(Enum):
@@ -58,3 +55,9 @@ class DetectorBank(Enum):
 
 CIFPeaksMinIntensity = NewType("CIFPeaksMinIntensity", sc.Variable)
 """Minimum peak intensity for peaks from CIF file to be included in :py:`DHKLList`."""
+
+
+class TofDetector(sciline.Scope[RunType, sc.DataArray], sc.DataArray):
+    """
+    Detector with a time-of-flight coordinate
+    """
diff --git a/src/ess/powder/conversion.py b/src/ess/powder/conversion.py
index 234e9aed..eda605bb 100644
--- a/src/ess/powder/conversion.py
+++ b/src/ess/powder/conversion.py
@@ -60,7 +60,7 @@ def _dspacing_from_diff_calibration_a0_impl(t, t0, c):
 
 
 def _dspacing_from_diff_calibration(
-    tof: sc.Variable,
+    unwrapped_eto: sc.Variable,
     tzero: sc.Variable,
     difa: sc.Variable,
     difc: sc.Variable,
@@ -71,7 +71,7 @@ def _dspacing_from_diff_calibration(
 
     d-spacing is the positive solution of
 
-    .. math:: \mathsf{tof} = \mathsf{DIFA} * d^2 + \mathsf{DIFC} * d + t_0
+    .. math:: \mathsf{eto} = \mathsf{DIFA} * d^2 + \mathsf{DIFC} * d + t_0
 
     This function can be used with :func:`scipp.transform_coords`.
 
@@ -80,8 +80,10 @@ def _dspacing_from_diff_calibration(
     ess.powder.conversions.to_dspacing_with_calibration
     """
     if sc.all(difa == sc.scalar(0.0, unit=difa.unit)).value:
-        return _dspacing_from_diff_calibration_a0_impl(tof, tzero, difc)
-    return _dspacing_from_diff_calibration_generic_impl(tof, tzero, difa, difc)
+        return _dspacing_from_diff_calibration_a0_impl(unwrapped_eto, tzero, difc)
+    return _dspacing_from_diff_calibration_generic_impl(
+        unwrapped_eto, tzero, difa, difc
+    )
 
 
 def _consume_positions(position, sample_position, source_position):
diff --git a/tests/beer/mcstas_reduction_test.py b/tests/beer/mcstas_reduction_test.py
index 40caec52..32ac0875 100644
--- a/tests/beer/mcstas_reduction_test.py
+++ b/tests/beer/mcstas_reduction_test.py
@@ -1,6 +1,7 @@
 import numpy as np
 import scipp as sc
 import scippneutron as scn
+from ess.reduce.nexus.types import Filename, SampleRun
 from scipp.testing import assert_allclose
 
 from ess.beer import (
@@ -15,9 +16,7 @@
     mcstas_silicon_new_model,
 )
 from ess.beer.io import load_beer_mcstas, load_beer_mcstas_monitor
-from ess.beer.types import DetectorBank, DHKLList
-from ess.reduce.nexus.types import Filename, SampleRun
-from ess.reduce.time_of_flight.types import TofDetector
+from ess.beer.types import DetectorBank, DHKLList, TofDetector
 
 
 def test_can_reduce_using_known_peaks_workflow():
diff --git a/tests/dream/geant4_reduction_test.py b/tests/dream/geant4_reduction_test.py
index e4a11ddc..6aee136d 100644
--- a/tests/dream/geant4_reduction_test.py
+++ b/tests/dream/geant4_reduction_test.py
@@ -8,6 +8,9 @@
 import sciline
 import scipp as sc
 import scipp.testing
+from ess.reduce import unwrap
+from ess.reduce import workflow as reduce_workflow
+from ess.reduce.nexus.types import AnyRun
 from scippneutron import metadata
 from scippneutron._utils import elem_unit
 
@@ -31,12 +34,12 @@
     IntensityDspacingTwoTheta,
     IntensityTof,
     KeepEvents,
+    LookupTable,
+    LookupTableFilename,
     MonitorFilename,
     NeXusDetectorName,
     ReducedTofCIF,
     SampleRun,
-    TimeOfFlightLookupTable,
-    TimeOfFlightLookupTableFilename,
     TofMask,
     TwoThetaBins,
     TwoThetaMask,
@@ -44,9 +47,6 @@
     VanadiumRun,
     WavelengthMask,
 )
-from ess.reduce import time_of_flight
-from ess.reduce import workflow as reduce_workflow
-from ess.reduce.nexus.types import AnyRun
 
 params = {
     Filename[SampleRun]: dream.data.simulated_diamond_sample(small=True),
@@ -59,8 +59,10 @@
     CalibrationFilename: None,
     UncertaintyBroadcastMode: UncertaintyBroadcastMode.drop,
     DspacingBins: sc.linspace('dspacing', 0.0, 2.3434, 201, unit='angstrom'),
-    TofMask: lambda x: (x < sc.scalar(0.0, unit='us').to(unit=elem_unit(x)))
-    | (x > sc.scalar(86e3, unit='us').to(unit=elem_unit(x))),
+    TofMask: lambda x: (
+        (x < sc.scalar(0.0, unit='us').to(unit=elem_unit(x)))
+        | (x > sc.scalar(86e3, unit='us').to(unit=elem_unit(x)))
+    ),
     TwoThetaMask: None,
     WavelengthMask: None,
     CIFAuthors: CIFAuthors(
@@ -112,7 +114,7 @@ def test_pipeline_can_compute_dspacing_result_without_empty_can(workflow):
 
 def test_pipeline_can_compute_dspacing_result_using_lookup_table_filename(workflow):
     workflow = powder.with_pixel_mask_filenames(workflow, [])
-    workflow[TimeOfFlightLookupTableFilename] = dream.data.tof_lookup_table_high_flux()
+    workflow[LookupTableFilename] = dream.data.tof_lookup_table_high_flux()
     result = workflow.compute(EmptyCanSubtractedIofDspacing)
     assert result.sizes == {'dspacing': len(params[DspacingBins]) - 1}
     assert sc.identical(result.coords['dspacing'], params[DspacingBins])
@@ -120,29 +122,28 @@ def test_pipeline_can_compute_dspacing_result_using_lookup_table_filename(workfl
 
 @pytest.fixture(scope="module")
 def dream_tof_lookup_table():
-    lut_wf = time_of_flight.TofLookupTableWorkflow()
-    lut_wf[time_of_flight.DiskChoppers[AnyRun]] = dream.beamline.choppers(
+    lut_wf = unwrap.LookupTableWorkflow()
+    lut_wf[unwrap.DiskChoppers[AnyRun]] = dream.beamline.choppers(
         dream.beamline.InstrumentConfiguration.high_flux_BC215
     )
-    lut_wf[time_of_flight.SourcePosition] = sc.vector(value=[0, 0, -76.55], unit="m")
-    lut_wf[time_of_flight.NumberOfSimulatedNeutrons] = 500_000
-    lut_wf[time_of_flight.SimulationSeed] = 555
-    lut_wf[time_of_flight.PulseStride] = 1
-    lut_wf[time_of_flight.LtotalRange] = (
+    lut_wf[unwrap.SourcePosition] = sc.vector(value=[0, 0, -76.55], unit="m")
+    lut_wf[unwrap.NumberOfSimulatedNeutrons] = 500_000
+    lut_wf[unwrap.SimulationSeed] = 555
+    lut_wf[unwrap.PulseStride] = 1
+    lut_wf[unwrap.LtotalRange] = (
         sc.scalar(60.0, unit="m"),
         sc.scalar(80.0, unit="m"),
     )
-    lut_wf[time_of_flight.DistanceResolution] = sc.scalar(0.1, unit="m")
-    lut_wf[time_of_flight.TimeResolution] = sc.scalar(250.0, unit='us')
-    lut_wf[time_of_flight.LookupTableRelativeErrorThreshold] = 0.02
-    return lut_wf.compute(time_of_flight.TimeOfFlightLookupTable)
+    lut_wf[unwrap.DistanceResolution] = sc.scalar(0.1, unit="m")
+    lut_wf[unwrap.TimeResolution] = sc.scalar(250.0, unit='us')
+    return lut_wf.compute(unwrap.LookupTable)
 
 
 def test_pipeline_can_compute_dspacing_result_using_custom_built_tof_lookup(
     workflow, dream_tof_lookup_table
 ):
     workflow = powder.with_pixel_mask_filenames(workflow, [])
-    workflow[TimeOfFlightLookupTable] = dream_tof_lookup_table
+    workflow[LookupTable] = dream_tof_lookup_table
 
     result = workflow.compute(IntensityDspacing[SampleRun])
     assert result.sizes == {'dspacing': len(params[DspacingBins]) - 1}

From b426ce164eab25c5fe55884420a77950756494c6 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 20 Mar 2026 16:02:50 +0100
Subject: [PATCH 09/10] add manual conversion to wavelength for powgen

---
 src/ess/powder/conversion.py     | 16 ++++++++-----
 src/ess/powder/types.py          |  2 +-
 src/ess/snspowder/powgen/data.py | 40 ++++++++++++++++++++++++++++++--
 3 files changed, 49 insertions(+), 9 deletions(-)

diff --git a/src/ess/powder/conversion.py b/src/ess/powder/conversion.py
index eda605bb..826793ef 100644
--- a/src/ess/powder/conversion.py
+++ b/src/ess/powder/conversion.py
@@ -60,7 +60,9 @@ def _dspacing_from_diff_calibration_a0_impl(t, t0, c):
 
 
 def _dspacing_from_diff_calibration(
-    unwrapped_eto: sc.Variable,
+    # TODO: should not be tof here but a time-of-arrival
+    # See https://github.com/scipp/essdiffraction/issues/255
+    tof: sc.Variable,
     tzero: sc.Variable,
     difa: sc.Variable,
     difc: sc.Variable,
@@ -71,7 +73,7 @@ def _dspacing_from_diff_calibration(
 
     d-spacing is the positive solution of
 
-    .. math:: \mathsf{eto} = \mathsf{DIFA} * d^2 + \mathsf{DIFC} * d + t_0
+    .. math:: \mathsf{tof} = \mathsf{DIFA} * d^2 + \mathsf{DIFC} * d + t_0
 
     This function can be used with :func:`scipp.transform_coords`.
 
@@ -80,10 +82,8 @@ def _dspacing_from_diff_calibration(
     ess.powder.conversions.to_dspacing_with_calibration
     """
     if sc.all(difa == sc.scalar(0.0, unit=difa.unit)).value:
-        return _dspacing_from_diff_calibration_a0_impl(unwrapped_eto, tzero, difc)
-    return _dspacing_from_diff_calibration_generic_impl(
-        unwrapped_eto, tzero, difa, difc
-    )
+        return _dspacing_from_diff_calibration_a0_impl(tof, tzero, difc)
+    return _dspacing_from_diff_calibration_generic_impl(tof, tzero, difa, difc)
 
 
 def _consume_positions(position, sample_position, source_position):
@@ -122,6 +122,10 @@ def to_dspacing_with_calibration(
     ess.powder.conversions.dspacing_from_diff_calibration
     """
     out = merge_calibration(into=data, calibration=calibration)
+
+    # TODO: we should not be restoring tof here, as the calibration should be converting
+    # a time of arrival to d-spacing, and not a tof.
+    # We defer this to a later step: https://github.com/scipp/essdiffraction/issues/255
     # Restore tof from wavelength
     out = out.transform_coords("tof", graph=graph, keep_intermediate=False)
 
diff --git a/src/ess/powder/types.py b/src/ess/powder/types.py
index 65d12b2e..d7f4afe9 100644
--- a/src/ess/powder/types.py
+++ b/src/ess/powder/types.py
@@ -194,7 +194,7 @@ class RawDataAndMetadata(sciline.Scope[RunType, sc.DataGroup], sc.DataGroup):
 
 
 TofMask = NewType("TofMask", Callable | None)
-"""TofMask is a callable that returns a mask for a given TofData."""
+"""TofMask is a callable that returns a mask for masking time-of-flight regions."""
 
 
 TwoThetaMask = NewType("TwoThetaMask", Callable | None)
diff --git a/src/ess/snspowder/powgen/data.py b/src/ess/snspowder/powgen/data.py
index 140d3a58..8be882b4 100644
--- a/src/ess/snspowder/powgen/data.py
+++ b/src/ess/snspowder/powgen/data.py
@@ -5,22 +5,38 @@
 
 from pathlib import Path
 
+import sciline as sl
 import scipp as sc
 import scippnexus as snx
+from ess.reduce.data import Entry, make_registry
 
 from ess.powder.types import (
     AccumulatedProtonCharge,
     CalibrationData,
     CalibrationFilename,
     DetectorBankSizes,
+    ElasticCoordTransformGraph,
     Filename,
+    MonitorCoordTransformGraph,
+    MonitorType,
     Position,
     ProtonCharge,
     RawDataAndMetadata,
     RunType,
-    TofDetector,
+    WavelengthDetector,
+    WavelengthMonitor,
 )
-from ess.reduce.data import Entry, make_registry
+
+
+class TofDetector(sl.Scope[RunType, sc.DataArray], sc.DataArray):
+    """
+    Detector with a time-of-flight coordinate
+    """
+
+
+class TofMonitor(sl.Scope[RunType, MonitorType, sc.DataArray], sc.DataArray):
+    """Monitor data with time-of-flight coordinate."""
+
 
 _registry = make_registry(
     "ess/powgen",
@@ -234,6 +250,24 @@ def sample_position(dg: RawDataAndMetadata[RunType]) -> Position[snx.NXsample, R
     return Position[snx.NXsample, RunType](dg["data"].coords["sample_position"])
 
 
+def convert_detector_to_wavelength(
+    da: TofDetector[RunType],
+    graph: ElasticCoordTransformGraph[RunType],
+) -> WavelengthDetector[RunType]:
+    return WavelengthDetector[RunType](
+        da.transform_coords("wavelength", graph=graph, keep_intermediate=False)
+    )
+
+
+def convert_monitor_to_wavelength(
+    monitor: TofMonitor[RunType, MonitorType],
+    graph: MonitorCoordTransformGraph[RunType],
+) -> WavelengthMonitor[RunType, MonitorType]:
+    return WavelengthMonitor[RunType, MonitorType](
+        monitor.transform_coords("wavelength", graph=graph, keep_intermediate=False)
+    )
+
+
 providers = (
     pooch_load,
     pooch_load_calibration,
@@ -242,5 +276,7 @@ def sample_position(dg: RawDataAndMetadata[RunType]) -> Position[snx.NXsample, R
     extract_raw_data,
     sample_position,
     source_position,
+    convert_detector_to_wavelength,
+    convert_monitor_to_wavelength,
 )
 """Sciline Providers for loading POWGEN data."""

From 1cad020bed0fb3000eee9a3e57f21e0cad603541 Mon Sep 17 00:00:00 2001
From: Neil Vaytet <neil.vaytet@ess.eu>
Date: Fri, 20 Mar 2026 16:11:05 +0100
Subject: [PATCH 10/10] fix dream geant4 tests

---
 tests/dream/geant4_reduction_test.py | 13 +++++--------
 1 file changed, 5 insertions(+), 8 deletions(-)

diff --git a/tests/dream/geant4_reduction_test.py b/tests/dream/geant4_reduction_test.py
index 6aee136d..a82c5486 100644
--- a/tests/dream/geant4_reduction_test.py
+++ b/tests/dream/geant4_reduction_test.py
@@ -59,10 +59,7 @@
     CalibrationFilename: None,
     UncertaintyBroadcastMode: UncertaintyBroadcastMode.drop,
     DspacingBins: sc.linspace('dspacing', 0.0, 2.3434, 201, unit='angstrom'),
-    TofMask: lambda x: (
-        (x < sc.scalar(0.0, unit='us').to(unit=elem_unit(x)))
-        | (x > sc.scalar(86e3, unit='us').to(unit=elem_unit(x)))
-    ),
+    TofMask: None,
     TwoThetaMask: None,
     WavelengthMask: None,
     CIFAuthors: CIFAuthors(
@@ -114,14 +111,14 @@ def test_pipeline_can_compute_dspacing_result_without_empty_can(workflow):
 
 def test_pipeline_can_compute_dspacing_result_using_lookup_table_filename(workflow):
     workflow = powder.with_pixel_mask_filenames(workflow, [])
-    workflow[LookupTableFilename] = dream.data.tof_lookup_table_high_flux()
+    workflow[LookupTableFilename] = dream.data.lookup_table_high_flux()
     result = workflow.compute(EmptyCanSubtractedIofDspacing)
     assert result.sizes == {'dspacing': len(params[DspacingBins]) - 1}
     assert sc.identical(result.coords['dspacing'], params[DspacingBins])
 
 
 @pytest.fixture(scope="module")
-def dream_tof_lookup_table():
+def dream_lookup_table():
     lut_wf = unwrap.LookupTableWorkflow()
     lut_wf[unwrap.DiskChoppers[AnyRun]] = dream.beamline.choppers(
         dream.beamline.InstrumentConfiguration.high_flux_BC215
@@ -140,10 +137,10 @@ def dream_tof_lookup_table():
 
 
 def test_pipeline_can_compute_dspacing_result_using_custom_built_tof_lookup(
-    workflow, dream_tof_lookup_table
+    workflow, dream_lookup_table
 ):
     workflow = powder.with_pixel_mask_filenames(workflow, [])
-    workflow[LookupTable] = dream_tof_lookup_table
+    workflow[LookupTable] = dream_lookup_table
 
     result = workflow.compute(IntensityDspacing[SampleRun])
     assert result.sizes == {'dspacing': len(params[DspacingBins]) - 1}