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AdV-DAQ (Calibration)
rolland - 10:19 Tuesday 22 January 2019 (44473) Print this report
Subtraction of CAL_NE,WE_MIR_Z_NOISE channels in HRec

HRec has been restarted at 9h15 LT to add the subtraction of the CAL_NE,WE_MIR_Z_NOISE channels between h_raw and h channels. The lines sent via these channels as external noise should now be reduced in the hoft_20000Hz channel (37.5, 56.5, 77.5, 106.5, 107.5, 137.5, 206.5 and 406.5 Hz). The lines from PCals are not yet subtracted.

Comments to this report:
mwas - 14:31 Saturday 26 January 2019 (44545) Print this report
The calibration line subtraction has not been enabled for the reconstructions down with a single PD (HrecPD1 and HrecPD2).
Given that light is only on 1 PD, this allows an easy comparison of the reconstruction with and without subtraction.

Figure 1 shows the specta agree very well, and that in general the calibration lines are nicely subtracted.
Figure 2 is a nice example with 77.5Hz line and a bit of noise around it nicely removed
Figure 3 is a bad example, the lines at 106.5 and 107.5 are still a factor 20 above the noise floor after subtraction (for 50mHz frequency bins), so there is room to improve the subtraction (or a need to reduce a bit these calibration lines).
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