I Data needed: Relative permittivity of air

[WhiteHaired]

Where can I found values of the relative permittivity of air at different temperatures, frequencies, pressure, humidity, etc. or its dependence?
I'm particularly interested in data around 1.4 GHz, 25ºC, 1 atm. 50% hum.

Thanks in advance.

 

[berkeman]

Where can I found values of the relative permittivity of air at different temperatures, frequencies, pressure, humidity, etc. or its dependence?
I'm particularly interested in data around 1.4 GHz, 25ºC, 1 atm. 50% hum.

Thanks in advance.

Google is your friend. What have you found so far with your Google searches? Have you found numerous websites with information on this, but not one or two of the values that you need? What accuracy do you need the data to? What is the application?

 

[WhiteHaired]

Google is your friend. What have you found so far with your Google searches? Have you found numerous websites with information on this, but not one or two of the values that you need? What accuracy do you need the data to? What is the application?

In this case, Google is not my friend, or it is not enough. Indeed there are numerous websites where the data appears, but not with sufficient accuracy or without information on temperature, frequency, reliable reference, etc. For example, values like 1, 10006, 1000589, 10005364, 1000524, etc. are found.
Do a search for yourself and you will see what I say.
The application for which I need the data requires a precision of 1e-5 and at 25ºC, 1 atm, 50% hum, 1.4 GHz approximately, or some formula that allows obtaining it for those conditions and a reliable reference that can be cited in a paper.
Can anyone help, please?