From 0c48127dd42a24300541cc96fe60430a99eb0a5a Mon Sep 17 00:00:00 2001 From: arrell_c Date: Tue, 26 Sep 2023 14:17:31 +0200 Subject: [PATCH] Create Aramis Intensity Diagnostics/PBPS data --- Aramis-Intensity-Diagnostics/PBPS-data.md | 46 +++++++++++++++++++++++ 1 file changed, 46 insertions(+) create mode 100644 Aramis-Intensity-Diagnostics/PBPS-data.md diff --git a/Aramis-Intensity-Diagnostics/PBPS-data.md b/Aramis-Intensity-Diagnostics/PBPS-data.md new file mode 100644 index 0000000..cfdd859 --- /dev/null +++ b/Aramis-Intensity-Diagnostics/PBPS-data.md @@ -0,0 +1,46 @@ +## Channel list +All PSSS data channels are listed in the following sheet: + +[Sheet of PSSS data channels](https://docs.google.com/spreadsheets/d/16Hz7MZR3E7-OmLHfakkT2K6yPMFUzp4eIFZxrzXWjFk/edit?usp=sharing) + +## Nomenclature + +| Style | Meaning| +|----------|----------| +| SARFE10-PSSS059:**SPECTRUM***|Raw spectral data | +| SARFE10-PSSS059:**FIT*** | Results of Gaussian fit | +| SARFE10-PSSS059:**SPECT*** | Statistics from the raw (without fit) spectrum | +| SARFE10-PSSS059:**AVG*** | Data calculated from average (not single shot) spectra | + +## Concepts +**Width and center** + +Spectral width and central energy are calculated by both a Gaussian fit and directly from the spectra. Depending on the spectral intensity profile, the Gaussian may return a poor representation of the spectra, for example for a spectral with a long tail. Before both fitting and calculation the spiky single shot spectra are smoothed with a savgol filter: + +``` +# smooth the spectrum with savgol filter with 51 window size and 3rd order polynomial +smoothed_spectrum = scipy.signal.savgol_filter(spectrum, 51, 3) +``` + +The standard deviation and center of mass for the spectra are calculated as: + +``` +smoothed_spectrum_normed = smoothed_spectrum / np.sum(smoothed_spectrum) +spectrum_com = np.sum(axis * smoothed_spectrum_normed) +spectrum_std = np.sqrt(np.sum((axis - spectrum_com) ** 2 * smoothed_spectrum_normed)) +``` + +**Relative energy spread** + +Channels ending in **RES** are a measure of the relative energy spread in units of ‰. For **FIT** data the relative energy spread is calculated as: + +$`\frac{2.355*\sigma}{\mu}`$ + +and for directly calculated values (**SPECT**): + +$`\frac{2.355*RMS}{\text{Center of mass}}`$ + +where the factor or 2.355 is included to allow these values to be comparable. + +## Data flow schematic + \ No newline at end of file