ID:
40

Name:
J_NO2 Measurement at variable Vis light intensities

Instrument ID:
Model 42i Trace Level Chemiluminescence NO-NO2-NOx Analyzer (#422)

Chamber:
1-White (1W)

Date of characterization experiment:
2021-07-22

Months since calibration:
0

Measurement technique:
See instrument metafiles. Sampling residence time of the inlet and instrument is sufficiently short so that dark recombination reaction is insignificant.

Photolysis frequency of NO₂ with max lighting [Hz]:
0.00056

Photolysis frequency of H₂O₂ with max lighting [Hz]:

Photolysis frequency of O₃ with max lighting [Hz]:

Total number of lights:

Light percentage on:
100

Light intensity:
See characterization metafiles on calibrated light flux intensities for each light type (UV and Vis)

Light source type:
VISIBLE_LIGHT_TYPE: T5HO tubes (54W) VISIBLE_LIGHT_PEAK_EMISSION_WAVELENGTH (nm): 490

Position and pattern of lights:
See chamber description

Data collection description:
The method follows the J_NO2 light characterization protocol designed by ICARUS working groups. ~ 40ppb of NO2 added to clean chamber, UV or Vis lights step through multiple light intensities. Monitored gas concentrations (NO, NO2, NOx and Ozone) allowed to reach steady-state at each step.

Data analysis description:
J_NO2 calculated at each step using steady-state equation balancing NO2 photolysis (NO2 + hv -> NO + O; O + O2 -> O3) and O3 and NO recombination (O3 + NO -> NO2 + O2)

Link to supplemental information:
https://docs.google.com/document/d/1G5WUuIFpzBWkSGsmQ6zzGeLqDht_VIVFCTLAyYV5JhY/edit?usp=sharing

Additional notes:
See link to a google doc with figures showing time series of J_NO2 calculations Data file contains experiment with measurements of both UV and Vis

Characterization data file:
T202181123_Timeline.csv