Research note
Aperture diagnostics on the real sector 56 product set
A threshold aperture run on the HD 209458 b target pixel file, compared with the mission SAP and PDCSAP columns on one common quality mask.
This is a product comparison on one real SPOC target pixel file and one real SPOC light curve. It does not validate the SPOC pipeline. It is a diagnostic on one common quality mask.
Aperture
| Quantity | Value |
|---|---|
| Aperture pixels | 14 |
| Annulus pixels | 23 |
| Threshold fraction of peak excess | 0.05 |
| Threshold value | 2,537.830983 e-/s |
| Background | 500.332367 e-/s |
| Aperture touches image edge | no |
The configuration is the module default: threshold fraction 0.05, annulus radii 2.0 to 3.5 pixels, and pairing tolerance 60.0 s.
Cadence counts
| Quantity | Cadences |
|---|---|
| Input rows | 20,079 |
| Passed the quality mask | 19,612 |
| Retained by the aperture extraction | 19,612 |
| Common-mask cadences | 18,792 |
The common mask requires the same quality mask on both inputs and a valid aperture extraction. The comparison paired 18,792 cadences with a maximum time offset of 0.0 s.
Comparison
Both the aperture series and each mission series are divided by their median on the common mask. The RMS difference is reported in ppm of the normalized series.
| Series | Points | Pearson r | RMS difference (ppm) |
|---|---|---|---|
| SAP | 18,792 | 0.961576 | 790.564330 |
| PDCSAP | 18,792 | 0.933892 | 1,019.426274 |
Limits
- No detrending, transit fit, folding, or timing measurement was performed.
- A correlation with SAP and PDCSAP is not a validation of the mission pipeline.
- The comparison uses one quality mask and one target in one sector.
- No transit, depth, duration, period, ephemeris, or mid-transit time is measured or claimed.
Evidence in the repository
Topics: light-curves, astronomy-methods, open-science