Vis Analysis Results Product¶

$SetSchemaPath vis/euc-vis-AnalysisResults.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¶

VIS_science_xml_out

Processing function using the data product¶

VIS

Proposed for inclusion in EAS/SAS¶

Yes

Data product elements¶

$PrintDataProductElements

Detailed description of the data product¶

The DpdVisAnalysisResults is a general product that can be filed by different pipeline. It is designed to store data quality control during the production of product.

VISProcessField DQC description¶

The analysis results is a .json file combining all the data quality control created during the processing of the calibrated(Quad)Frame exposure. This is very useful for determining which data is really usable for science and which not.

Comsic Rays¶

For check if the data is contaminated by X-rays, we compute the ratio of cosmic rays detection by LA Cosmicx.

For the moment, we have determine that data with a number of cosmic rays above 3.0% for a nominal exposition is data that cannot be used. For normalise to the exposure time, we also need to add the readout time (70 s) for taking account that cosmics rays can arrive also during this time. In the fact, this type of data can be used with caution due to the fact that the X-rays affect only some quadrant and not all the FPA. Above this threshold, a lot of cosmic rays can be missed by LA Cosmicx.

In PF-13 this DQC was saved in ratio. In PF-14 and above it was saved in percent.

We save the ratio of pixel with the flag COSMIC per detector in quadrant.cosmic_pixel_percent.

We calculate the maximum and the mean of this ratio per detector and stored it in this 2 indicatore :

FPA.max_cosmic_percent: These correspond to the values quadrant.cosmic_pixel_percent of the quadrant with the maximum percentage of pixels with the COSMIC flag in the FPA. If this indicator is high it may indicate an X-Rays pattern.

FPA.cosmic_pixel_percent: These correspond to the mean percentage of pixels with the COSMIC flag in the FPA. This may indicate a proton shower or a realy high event on a quadrant or few.

We also used the flags CR_REGION (added in PF 14.0) for indicate if the quadrant is above a threshold define in the config file of the VIS-PF. In PF-14 the thredsold was 3.0%. It was growed up to 5.0% in PF-15. The number of quadrant masked by CR_REGION is stored in FPA.cr_regions_count.

RA/DEC residual¶

The requirement R-VIS-CAL-F-010 is define as ‘astrometric residual $< 3$ mas’.

The mean residual for each exposure is save in vis_res_mean.

The RA/DEC mean and std is stored individualy in:

ra_res_final_mean ; ra_res_final_sdr ; dec_res_final_mean ; dec_res_final_sdr.

Spread model¶

FPA.spreadmodel_peak: It is the peak of the spread model corresponding to the star in the flux_auto vs spread_model for $1.5 <$ log10( FLUX_AUTO/FLUXERR_AUTO) $< 2.5$. It is a good indicator of the quality of the guidance. We have estimated that spread model peak above 0.002 correspond to data with guiding errors.

The FPA.spreadmodel_sigma is standard deviation of the gaussian fit of the histogram of SExtractor spread model values.

Moment¶

This DQC was added in PF-14.

During the data processing we calculate the median and the standard deviation of e1, e2, r2 of the stars based on Konrad Kuijken methode. PF-14.0.4 add the calculation of t1, t2, c1, c2.

All this DQC are daved in the format FPA.moment_{r2/e1/e2/t1/t2/c1/c2}_{med/std}

From this measure, we can derive a score with :

\[\begin{split}& \frac{(e2_{med}-e2m)^2}{vare2} + (r2_{med}-r2m)^2*covinv[0,0]+ \\ & 2*(r2_{med}-r2m)*(e1_{med}-e1m)*covinv[1,0]+(e1_{med}-e1m)^2*covinv[1,1]\end{split}\]

Where:

r2m=1.9233812949640285
e1m=-0.023129496402877696
e2m=0.002733812949640288
cov00=0.0005422666041080192
cov01=-0.00011841403399019925
cov11=4.4881659889479756e-05
vare2=5.332022152062523e-06
covinv=np.linalg.inv([[cov00,cov01],[cov01,cov11]])

calculated from a reference field.

By statistical analysis, we defined that a score higher than 60 is bad.

Zero point¶

For quality control we calculate a zero point by comparing with Gaia.

FPA.zero_point: VIS zero point calculated by comparison with Gaia data.

FPA.zp_rms: Standard deviation of the VIS zero point.

A zero point for each quadrant is also available in {quadrant}.zp_mean and {quadrant}.zp_rms.