radiation constants

https://doi.org/10.1351/goldbook.R05051
Fundamental physical constants characterizing black body radiation. The first radiation constant is \(c_{1} = 2\ \pi \ h\ c_{0}^{2}=3.741\,7749(22)\times 10^{-16}\ \text{W m}^{2}\), the second is \(c_{2} = \frac{h\ c_{0}}{k}=1.438\,769(12)\times 10^{-2}\ \text{m K}\), where \(h\) is the @[email protected] \(c_{0}\) the speed of light and \(k\) the @[email protected]
Source:
CODATA Bull. 1986, 63, 1 [Terms] [Book]