Vis Trap Pumping Results Product¶

$SetSchemaPath vis/euc-vis-TrapPumpingResults.xsd

Data product name¶

$PrintDataProductName

Data product custodian¶

$PrintDataProductCustodian

Name of the Schema file¶

$PrintSchemaFilename

Last Edited for DPDD Version¶

1.1

Processing Element(s) creating/using the data product¶

Trap pumping calibration pipeline.

Processing function using the data product¶

VIS

Proposed for inclusion in EAS/SAS¶

Yes

Data product elements¶

$PrintDataProductElements

Detailed description of the data product¶

This product contains the interim results of the trap pumping calibration pipeline. The product is a file container, which holds a CSV file containing results from analysis of the vertical (VTP) or (multiple-readout) serial (STP) trap pumping raw frames. These are used to determine how many traps are present in each quadrant, their emission time constants and “pumping efficiencies”, and their locations (pixel and phase). Each row describes one trap.

For VTP, the columns in the CSV are:

Column name	Description
`row`	The pixel row within the quadrant where the trap is located. This is with the origin at readout (i.e. rotated from the FPA orientation).
`column`	The pixel column within the quadrant where the trap is located. This is with the origin at readout (i.e. rotated from the FPA orientation).
`phase`	The phase within the pixel containing the trap.
`model_name`	The name of the best-fit model class. (These are Python class names from the trap pumping analysis code.) `TphOriginalModel` is the only valid model for VTP. `ConstantModel` indicates a bad fit – a constant fitted better than the model – and is retained for debugging. In the edge case that the pixel is flagged as a cosmic in >6 of the TP frames, this column is empty (no fit is performed, since the data is considered too sparse).
`tau_e`	The emission time constant, in microseconds, if `model_name` is `TphOriginalModel`.
`P_c`	The pumping efficiency, if `model_name` is `TphOriginalModel`. Also called probability of capture.
`k`	Additive constant, should be close to zero.
`c`	Constant, only defined if `model_name` is `ConstantModel`.
(Numerical)	There are 11 columns whose headers are the trap pumping TOI values, in microseconds, and whose values are the dipole intensity (half the difference between the two sides of the dipole) at that TOI. These are retained for further analysis and debugging.
`cr_flags`	Integer representation of 11-bit binary number indicating TOIs for which dipoles have been flagged as cosmics and excluded from the fitting. The most significant bit of the binary representation flags TOI 10 µs and the least significant 16000 µs. Retained for further analysis.

For STP, the columns in the CSV are:

Column name	Description
`column`	The pixel column within the quadrant where the trap is located. This is with the origin at readout (i.e. rotated from the FPA orientation).
`phase`	The phase within the pixel containing the trap.
`model_name`	The name of the best-fit model class. `DwellPhase1Model` or `DwellPhase2Model` are the only valid models for STP. Other models indicate neither model fitted well – these rows are retained for debugging.
`tau_e`	The emission time constant, in microseconds, if `model_name` is `DwellPhase1Model` or `DwellPhase2Model`.
`tau_c`	The capture time constant, in microseconds, if `model_name` is `DwellPhase1Model`.
`P_c`	The pumping efficiency, if `model_name` is `DwellPhase2Model`.
`k`	Additive constant used in both models. Should be close to zero.
`a`, `b`, `c`	Parameters used by other models indicating a bad fit (`LinearLogModel`, `ConstantModel`). Retained for debugging.
(Numerical)	There are 8 columns whose headers are STP dwell time values, in microseconds, and whose values are the dipole intensity (half the difference between the two sides of the dipole) at that dwell time. These are retained for further analysis and debugging.
`cr_flags`	Integer representation of 8-bit binary number to be used for cosmics flagging. Not yet implemented, so currently set to zero.

The product contains two QualityParameterStorage elements, which point to archived tarballs with quality control stats and plots. The stats archive contains ASCII files with “frames” stats (VTP only) and “output” stats. The frames stats are, for each VTP frame and quadrant, the mean (mean_col_means) and standard deviation (std_col_means) of the mean column values, after CI reference subtraction and sigma clipping at 3 sigma. The output stats are, for each quadrant, the number of traps found (num_traps) and, where applicable, the number of traps affected by cosmics (num_cr_affected). The plots are histograms of tau_e and heatmaps of P_c vs. tau_e, each presented in a 6x6 (FPA) grid per file, with separate files for each quadrant. The tarballs are also included in an associated DpdVisAnalysisResults product.

This product will ultimately be used as an input to the creation of the DpdVisTrapPumpingModel product, which will feed into CTI calibration, but it will remain in use for more detailed monitoring of the evolution of CCD defects.