LRO Diviner radiance values

[Susie Slavney]

Answers from the Diviner science team to questions from a Diviner user.

Q: The radiance unit mentioned in the lbl file is W m**-2 sr**-1, the term corresponding to frequency is missing. Why is it so?

A: Radiance has units of W m**-2 sr**-1 and does not include a frequency term,units of spectral radiance include frequency.

Q: How are the BT values calculated from radiance? Are there any preprocessing steps involved in this calculation? Simple calculation using the Planck's function (for the central wavelength) does not match the BT values given in the file.

A: The spectral radiance is integrated across the spectral passbands. The Diviner channel spectral responses are described in:

Paige, D. A., Foote, M. C., Greenhagen, B. T., Schofield, J. T., Calcutt, S., Vasavada, A. R., et al. (2010). The Lunar Reconnaissance Orbiter
Diviner Lunar Radiometer Experiment. Space Science Reviews, 150(1–4), 125–160. https://link.springer.com/article/10.1007/s11214-009-9529-2