B Temperature based on colour index using Planck's law

AI Thread Summary
The discussion focuses on determining the temperature of stars using their B-V magnitude through Planck's law. The user seeks guidance on solving for temperature (T) numerically, expressing difficulty in integrating over the filter's bandpass. Suggestions include using numerical methods and programming languages like Mathematica, Matlab, or Python for integration. The user expresses a lack of familiarity with coding but considers using graphical methods instead. Overall, the conversation emphasizes the importance of numerical integration in applying Planck's law for temperature calculations.
heavystray
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Hi, I'm trying to find temperature of stars using the stars' B-V magnitude by using the Planck law. However i do not know how to solve for T (assume other quantities are all given and determined first). Any idea how to do so? I already tried to do it but reach a dead end. Here I attached the Planck equation. h is Planck's constant, k is boltzman's constant, c is the speed of light,

upload_2018-1-23_0-13-28.png
 

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It should be a simple matter to solve for T numerically. To do it right, you really should integrate λ over the bandpass of the filter.
 
phyzguy said:
It should be a simple matter to solve for T numerically. To do it right, you really should integrate λ over the bandpass of the filter.
How do you integrate it tho? It'd be great if you can show step by step on how to do it, thanks for answering.
 
heavystray said:
How do you integrate it tho? It'd be great if you can show step by step on how to do it, thanks for answering.

I would do that numerically as well. You can write some simple code in Mathematica, Matlab, or Python to do it. Do you know how to use any of those?
 
phyzguy said:
I would do that numerically as well. You can write some simple code in Mathematica, Matlab, or Python to do it. Do you know how to use any of those?
hmmm no..but i think it's ok for now...i'll just solve it using graph, thanks!
 
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