Berenice

From Βερενíκη, Ancient Macedonian form of the Attic Greek, Φερενíκη: she, who brings victory.

This city produces the spectrum of dark noise of the SiPMs. This is achieved by binning either the \(pe\) or \(ADC\) content of each raw WF sample. Some slices will have only electronic noise while others will contain one or more dark counts. The resulting spectra give a representation of the SiPM charge in the absence of external light above detector ambient conditions.

Input

• /Run/events: list of the evt_number and the correspondent timestamp.

• /Run/runInfo: stores the run_number.

• /RD/sipmrwf: stores the raw waveform itself. It indicates the number of \(ADCs\) per time bin for each event and SiPM.

Output

• HIST/median: histogram values of the dark spectrum when the baseline substraction has been performed with the median of the waveform along with the \(ADCs\) to \(pes\) conversion (calibration).

• HIST/median_bins: bin values of the dark spectrum HIST/median.

• HIST/mode: histogram values of the dark spectrum when the baseline substraction has been performed with the mode of the waveform along with the \(ADCs\) to \(pes\) conversion (calibration).

• HIST/mode_bins: bin values of the dark spectrum HIST/mode.

• HIST/adc: histogram values of the dark spectrum when the baseline substraction has been performed with the mode of the waveform and no calibration.

• HIST/adc_bins: bin values of the dark spectrum HIST/adc_bins.

Config

Besides the Common arguments to every city, Berenice has the following arguments:

Parameter	Type	Description
min|max_bin	float	Lower/upper limit of the number of \(ADCs`\) of the waveform to be considered for the spectrum.
bin_width	int	Width of the bins for the spectrum.

Workflow

Berenice performs the following operations to obtain the dark spectra:

• Subtract the baseline

• Waveform calibration

• Waveform slicing

• Histogram the result

Subtract the baseline

Berenice has two options for the baseline substraction: using the median or the mode, analogously described in in Baseline subtraction of SiPM waveforms section of the Irene documentation.

Waveform calibration

In this step, the waveform in \(ADCs\) in converted to photoelectrons (\(pes\)). For this, the gains are loaded from the NEXT database.

This step is optional when subtracting the baseline using the mode of the waveform.

Waveform slicing

According to the selected min_bin, max_bin y bin_width configuration parameters the waveform will be sliced. An exaggerated slicing can be observed in the figure below with min_bin=100, max_bin=400 y bin_width=10:

Histogram the result

For each slice performed on the waveform in the previous section, it sums all the \(ADCs\) in each slice and adds an entry to the histogram. It repeats this for each waveform of the same sensor.