@@ -106,6 +106,9 @@ for selecting between :ref:`GetDetectorOffsets

<algm-GetDetectorOffsets>` and :ref:`GetDetOffsetsMultiPeaks

<algm-GetDetOffsetsMultiPeaks>`.

.. _calibration_tofpd_group_calibration-ref:

Group Calibration

~~~~~~~~~~~~~~~~~

...

...

@@ -115,6 +118,28 @@ the instrument in groups using a combination of :ref:`CrossCorrelate

<algm-GetDetectorOffsets>` and :ref:`PDCalibration

<algm-PDCalibration>`.

It works by performing the cross-correlations on only the detectors

within a group, after which the grouped detectors are merge together

to use with PDCalibration. The difc from the PDCalibration and

cross-correlation are combined using :ref:`CombineDiffCal

<algm-CombineDiffCal>`

The workflow follows these step:

#. Load data, usually diamond

#. Convert to d-spacing

#. CrossCorrelate a portion of the instrument according to the group information

#. GetDetectorOffsets to calculate offsets for individual pixels with a group

#. ConvertDiffCal to convert these constants to :math:`DIFC_{CC}`

#. Use :math:`DIFC_{CC}` to convert the origonal data to d-spacing. DiffractionFocus allows for combining a portion of the instrument into a single spectrum for improved statistics

#. Pick an arbitrary constant, :math:`DIFC_{arb}` to convert this combined spectrum back to time-of-flight

#. PDCalibration the combined spectrum to determine a conversion constant :math:`DIFC_{PD}`

#. Do math (below) to combine :math:`DIFC_{CC}`, :math:`DIFC_{arb}`, and :math:`DIFC_{PD}` into a new calibration constant, :math:`DIFC_{eff}`

- New algorithm :ref:`CombineDiffCal <algm-CombineDiffCal>` to calibrate groups of pixels after cross correlation so that diffraction peaks can be adjusted to the correct positions

- New script for doing calibration by groups, :ref:`PowderDiffractionCalibration <calibration_tofpd_group_calibration-ref>`