Tracking4D: update README, explaining new 'spatial_cut_rel' and...

Tracking4D: update README, explaining new 'spatial_cut_rel' and 'spatial_cut_abs', also improved wording for 'timing_cut_rel' and 'timing_cut_abs'

src/modules/Tracking4D/README.md

@@ -9,9 +9,10 @@ This module performs a basic tracking method.
 Clusters from the first plane in Z (named the seed plane) are related to clusters close in time on the other detector planes using straight line tracks. The DUT plane can be excluded from the track finding.
 
 ### Parameters
-* `time_cut_rel`: Number of standard deviations the `time_resolution` of one detector plane will be multiplied by, either the `time_resolution` of the first plane in Z or the current telescope plane, whichever is largest. This calculated value is then used as the maximum time difference allowed between clusters for association to a track. This allows the time cuts between different planes to be detector appropriate. By default, a relative time cut is applied. Absolute and relative time cuts are mutually exclusive. Defaults to `3.0`.
-* `time_cut_abs`: Specifies an absolute value for the maximum time difference allowed between clusters for association to the track. Absolute and relative time cuts are mutually exclusive. No default value.
-* `spatial_cut`: Maximum spatial distance in the XY plane allowed between clusters for association for the telescope planes. Default value is `0.2mm`.
+* `time_cut_rel`: Factor by which the `time_resolution` of each detector plane will be multiplied, either the `time_resolution` of the first plane in Z or the current telescope plane, whichever is largest. This calculated value is then used as the maximum time difference allowed between clusters and a track for association to the track. This allows the time cuts between different planes to be detector appropriate. By default, a relative time cut is applied. Absolute and relative time cuts are mutually exclusive. Defaults to `3.0`.
+* `time_cut_abs`: Specifies an absolute value for the maximum time difference allowed between clusters and a track for association to the track. Absolute and relative time cuts are mutually exclusive. No default value.
+* `spatial_cut_rel`: Factor by which the `spatial_resolution` in x and y of each detector plane will be multiplied. These calculated value are defining an ellipse which is then used as the maximum distance in the XY plane allowed between clusters and a track for association to the track. This allows the spatial cuts between different planes to be detector appropriate. By default, a relative spatial cut is applied. Absolute and relative spatial cuts are mutually exclusive. Defaults to `3.0`.
+* `spatial_cut_abs`: Specifies a set of absolute value (x and y) which defines an ellipse for the maximum spatial distance in the XY plane between clusters and a track for association to the track. Absolute and relative spatial cuts are mutually exclusive. No default value.
 * `min_hits_on_track`: Minium number of associated clusters needed to create a track, equivalent to the minimum number of planes required for each track. Default value is `6`.
 * `exclude_dut`: Boolean to choose if the DUT plane is included in the track finding. Default value is `true`.
 * `require_detectors`: Names of detectors which are required to have a cluster on the track. If a track does not have a cluster from all detectors listed here, it is rejected. If empty, no detector is required. Default is empty.