DiadFit: An Open-Source Python3 Tool for Peak fitting of Raman Data from silicate melts and CO2 fluids

We present DiadFit - an open-source Python3 tool for efficient processing of Raman spectroscopy data collected from fluidinclusions, melt inclusions and silicate melts. DiadFit is optimized to fit the characteristic peaks from CO2 fluids (Fermi diads,hot bands, 13C), gas species such as SO2, N2, solid precipitates (e.g., carbonates), and Ne emission lines with easily tweakablebackground positions and peak shapes. DiadFit’s peak fitting functions are used as part of a number of workflows optimizedfor quantification of CO2 in melt inclusion vapour bubbles and fluid inclusions. DiadFit can also convert between temperature,pressure and density using various CO2 and CO2-H2O equations of state (EOS), allowing calculation of fluid inclusion pressures(and depths in the crust), conversion of homogenization temperatures from microthermometry to CO2 density, and propagationof uncertainties associated with EOS calculations using Monte Carlo methods. There are also functions to quantify the area ratioof the silicate vs. H2O region of spectra collected on silicate glasses to determine H2O contents in glasses and melt inclusions.