Data and analysis supporting the article "Two-color measurements supporting a revised formulation for the refractive index of air," by PF Egan in Measurement Science and Technology (2026).
The measured data are in the files "data-GASNAME-2color.csv" where GASNAME is
* carbon dioxide
* oxygen
* bMixN787
* bMixN200
* dry air with a CO2 mole fraction of 388.86 ppm
* water
The bMixN787 and bMixN200 refer to binary mixtures of nitrogen + oxygen, where the mole fraction of nitrogen was 0.78706 and 0.19971, respectively.
Additionally, the water measurements performed at the six alternate C-band wavelengths are titled "data-water-2color-15XX.csv" where the 15XX denotes the nominal wavelength. The header information in those datafiles gives the exact frequency of the nominal C-band wavelength.
The analysis scripts called "plotGASNAME.py" reproduce the Figures 1, 2, 3, 4, 5, 6, and 7 from the article. The analysis scripts also output the Tables 1, 2, 3, and 4 in numerical format to the terminal prompt.
Some analyses either use literature data for a reference property, or compare present results with literature data. These literature data are included in the directory "lit". The scripts detailed above automatically load literature data as needed.
About this Dataset
| Title | Two-color measurements supporting a revised formulation for the refractive index of air |
|---|---|
| Description | Data and analysis supporting the article "Two-color measurements supporting a revised formulation for the refractive index of air," by PF Egan in Measurement Science and Technology (2026). The measured data are in the files "data-GASNAME-2color.csv" where GASNAME is * carbon dioxide * oxygen * bMixN787 * bMixN200 * dry air with a CO2 mole fraction of 388.86 ppm * water The bMixN787 and bMixN200 refer to binary mixtures of nitrogen + oxygen, where the mole fraction of nitrogen was 0.78706 and 0.19971, respectively. Additionally, the water measurements performed at the six alternate C-band wavelengths are titled "data-water-2color-15XX.csv" where the 15XX denotes the nominal wavelength. The header information in those datafiles gives the exact frequency of the nominal C-band wavelength. The analysis scripts called "plotGASNAME.py" reproduce the Figures 1, 2, 3, 4, 5, 6, and 7 from the article. The analysis scripts also output the Tables 1, 2, 3, and 4 in numerical format to the terminal prompt. Some analyses either use literature data for a reference property, or compare present results with literature data. These literature data are included in the directory "lit". The scripts detailed above automatically load literature data as needed. |
| Modified | 2026-04-13 00:00:00 |
| Publisher Name | National Institute of Standards and Technology |
| Contact | mailto:[email protected] |
| Keywords | Refractive index of air , Ciddor equation , Edlen equation , reference formulation , two-color interferometry |
{
"identifier": "ark:\/88434\/mds2-4155",
"accessLevel": "public",
"contactPoint": {
"hasEmail": "mailto:[email protected]",
"fn": "Patrick Egan"
},
"programCode": [
"006:045"
],
"landingPage": "https:\/\/data.nist.gov\/od\/id\/mds2-4155",
"title": "Two-color measurements supporting a revised formulation for the refractive index of air",
"description": "Data and analysis supporting the article \"Two-color measurements supporting a revised formulation for the refractive index of air,\" by PF Egan in Measurement Science and Technology (2026).\n\nThe measured data are in the files \"data-GASNAME-2color.csv\" where GASNAME is\n\n* carbon dioxide\n\n* oxygen\n\n* bMixN787\n\n* bMixN200\n\n* dry air with a CO2 mole fraction of 388.86 ppm\n\n* water\n\nThe bMixN787 and bMixN200 refer to binary mixtures of nitrogen + oxygen, where the mole fraction of nitrogen was 0.78706 and 0.19971, respectively.\n\nAdditionally, the water measurements performed at the six alternate C-band wavelengths are titled \"data-water-2color-15XX.csv\" where the 15XX denotes the nominal wavelength. The header information in those datafiles gives the exact frequency of the nominal C-band wavelength.\n\nThe analysis scripts called \"plotGASNAME.py\" reproduce the Figures 1, 2, 3, 4, 5, 6, and 7 from the article. The analysis scripts also output the Tables 1, 2, 3, and 4 in numerical format to the terminal prompt.\n\nSome analyses either use literature data for a reference property, or compare present results with literature data. These literature data are included in the directory \"lit\". The scripts detailed above automatically load literature data as needed.",
"language": [
"en"
],
"distribution": [
{
"downloadURL": "https:\/\/data.nist.gov\/od\/ds\/mds2-4155\/data-2colorAir.zip",
"mediaType": "application\/x-zip-compressed",
"title": "Two-color refractivity measurement of air and its constituents"
},
{
"downloadURL": "https:\/\/data.nist.gov\/od\/ds\/mds2-4155\/README.txt",
"mediaType": "text\/plain",
"title": "Readme file"
}
],
"bureauCode": [
"006:55"
],
"modified": "2026-04-13 00:00:00",
"publisher": {
"@type": "org:Organization",
"name": "National Institute of Standards and Technology"
},
"theme": [
"Metrology:Thermometry metrology",
"Metrology:Dimensional metrology"
],
"keyword": [
"Refractive index of air",
"Ciddor equation",
"Edlen equation",
"reference formulation",
"two-color interferometry"
]
}
