data_processing

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data_processing [2010/05/07 09:56] mdaeron |
data_processing [2013/01/22 04:15] mdaeron [(2) Compute the composition of your sample gas] |
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====== Data processing ====== | ====== Data processing ====== | ||

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+ | {{:gas_corrections.zip|Python code for gas corrections in the "imperial" reference frame}} | ||

===== CO2 data reduction ===== | ===== CO2 data reduction ===== | ||

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==== (2) Compute the composition of your sample gas ==== | ==== (2) Compute the composition of your sample gas ==== | ||

- | **(2.a) Measure the abundance ratios of your sample gas for masses 45 to 49** | + | **(2.a) Measure the abundance ratios of your sample gas for masses 45 to 49 (R<sub>45-Sample</sub>, etc.)** |

- | ...based on voltage measurements from your dual-inlet spectrometer: | + | ...based on peak height measurements from your dual-inlet spectrometer: |

* V<sub>44-Ref</sub> ... V<sub>49-Ref</sub> for your reference gas | * V<sub>44-Ref</sub> ... V<sub>49-Ref</sub> for your reference gas | ||

* V<sub>44-Sample</sub> ... V<sub>49-Sample</sub> for your sample gas | * V<sub>44-Sample</sub> ... V<sub>49-Sample</sub> for your sample gas | ||

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* R*<sub>49-Sample</sub> = C*<sub>45-Sample</sub> / C*<sub>44-Sample</sub> | * R*<sub>49-Sample</sub> = C*<sub>45-Sample</sub> / C*<sub>44-Sample</sub> | ||

- | **(3.b) Compute "raw" Δ values** | + | **(3.b) Compute raw Δ values** |

These Δ values are called "raw" because they have not yet been corrected for a number of analytical artifacts. Most importantly, we have assumed that your reference gas is in a stochastic state, which is unlikely. This is why raw Δ<sub>47</sub> values are typically underestimated by roughly the actual Δ<sub>47</sub> value of your reference gas. | These Δ values are called "raw" because they have not yet been corrected for a number of analytical artifacts. Most importantly, we have assumed that your reference gas is in a stochastic state, which is unlikely. This is why raw Δ<sub>47</sub> values are typically underestimated by roughly the actual Δ<sub>47</sub> value of your reference gas. |

data_processing.txt · Last modified: 2013/01/22 04:15 by mdaeron

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