Good
These observations present higher quality products after the background subtraction.
The extended calibrated spectra is not included in the data because it was not necessary for making the selections.
In order to improve the quality of the products the observations were reprocessed using 3 sigma - clipping method. The goal was to discard the outliers among the off-axis detectors in each observation and implement the background subtraction using only the remaining ones. This was done in the following way:
- For each array of detectors, SLW and SSW, a list was made containing the flux values of the smoothed spectra of each off-axis detector at a specific wavelength (950GHz for SLW and 1400 GHz for SSW). The median (medSLW and medSSW) and the median absolute deviation (madSLW and madSSW) of the lists were calculated.
- For each off-axis detector if the absolute value of the difference between the flux of the detector at the specific wavelength (950GHz/1400GHz) and the median (medSLW/medSSW) is bigger than 3 times the median absolute deviation then that off-axis detector is discarded.
- The detectors that were not discarded were used to obtain the smoothed median spectrum that was finally subtracted from the values of the central detectors.
Header parameters:
- Ratio SLW First Ring before background subtraction [%]: This parameter refers to the ratio of the flux of the first ring of SLW off-axis detectors to the flux of the central detector.
This was obtained by calculating the ratios of the flux of every SLW off-axis detector to the flux of the central detector for each value of frequency. In order to eliminate the dependancy on frequency, the median was taken for each SLW off-axis detector ratio array, resulting in a single value for every one of them. The final value resulted from taking the median from these last values.
The off-axis detectors used are SLWB2, SLWB3, SLWC2, SLWC4, SLWD2 and SLWD3.
- Ratio SSW First Ring before background subtraction [%]: This parameter refers to the ratio of the flux of the first ring of SSW off-axis detectors to the flux of the central detector.
This was obtained by calculating the ratios of the flux of every SSW off-axis detector to the flux of the central detector for each value of frequency. In order to eliminate the dependancy on frequency, the median was taken for each SSW off-axis detector ratio array, resulting in a single value for every one of them. The final value resulted from taking the median from these last values.
The off-axis detectors used are SSWD3, SSWC3, SSWC4, SSWE4 and SSWE3. (SSWD5 is a dead bolometer)
- Gap after background subtraction [Jy]: This value refers to the gap between the SLW and the SSW spectra of the central detector in the overlap region (944-1080 GHz) after the background subtraction has been done. It is the median of the difference between the flux of the SLW central detector and the flux of the SSW central detector for each frequency value.
- Relative Gap after background subtraction [%]: This value refers to the ratio of the gap between the SLW and the SSW spectra of the central detector to the flux of the SLW central detector in the overlap region (944-1080 GHz) after the background subtraction has been done. It is calculated dividing the difference between the flux of the SLW central detector and the flux of the SSW central detector by the flux of the SLW central detector for each frequency value.

- raDecOffset: The offset between the commanded position and the actual reconstructed pointing, which includes any systematic BSM offset (bsmOffset), but not the APE. Included in the observation's Meta Data.
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Laura Susana Alvarez Mera - 2015-12-07 ---
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