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NACO Quality Control:
ZERO POINT frames

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zeropoints
zeropointsall
strehl
QC1 database (advanced users): browse | plot
   Click on CURRENT to see the current trending (Health Check).
   Click on HISTORY to see the historical evolution of the trending.


The ZERO POINT frames (imaging standard stars) are obtained during the night time NACO operation for different instrumental setups. Each ZERO POINT consists of 5 raw frames. Dedicated pipeline recipe "naco_img_zpoint" builds 8 difference frames from those 5 input frames, rejects the minimum and maximum, and takes median of the remaining 6 zero points values. The subtraction pattern is: #1-#2, #2-#1, #2-#3, #3-#2, #3-#4, #4-3, #4-#5, #5-#4.

The conversion formula from ADUs to magnitudes is:

zmag = mag + 2.5 log10(flux/DIT)

where "zmag" is the computed zero point, "mag" is the known magnitude of the standard star in the observed band, "flux" is the flux measured in ADUs in the image and "DIT" is the detector integration time.

Note that the zero points do not include extinction nor the color correction.

This is an example of a pipeline product of the "naco_img_zpoint" recipe.


top zeropoints

QC1 parameters

parameter QC1 database: table, name procedure
"zpoint" naco_zp, zpoint zero point determined by the pipeline recipe naco_img_zpoint
"zpoint_rms" naco_zp, zpoint_rms RMS of the photometric zero point
"flux_counts" naco_zp, flux_counts mean flux in counts

The following health check plot shows the temporal evolution of the NACO photometric zero points (not corrected for extinction). Only the observations with broad filters Ks, J, H, and camera S27 are selected.

Trending

This trending plot shows the NACO zero points observed for filters Ks, J and H and all cameras and dichroics, as a function of time. Again, the zero points are not corrected for extinction.



top strehl

QC1 parameters

parameter QC1 database: table, name procedure
"strehl" naco_zp, strehl mean Strehl ratio determined by the pipeline
"strehl_rms" naco_zp, strehl_rms RMS of the Strehl ratio
"strehl_error" naco_zp, strehl_error error of the Strehl ratio

The health check plot shows the Strehl ratio calculated for the imaging standard star observations in filters Ks, J and H and camera S27.


 
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