<p>I've been trying to fit functions to plots showing photometric data for AGN from both optical and radio measurements, such as:</p>
<p><a href="https://i.sstatic.net/SUU4Q.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/SUU4Q.png" alt="enter image description here" /></a></p>
<p>but my supervisor says that this shouldn't be done; the radio and optical components must be treated separately. Why is this?</p>

CC BY-SA 4.0
2022-11-10T20:09:44.363Z
Eyeballing it, it looks like different lines would fit the radio and optical parts...  OB xkcd https://xkcd.com/2048/
James K
CC BY-SA 4.0
2022-11-10T21:42:13.107Z
The two components are caused by two different physical mechanisms — synchrotron radiation from the jet, and the revolving material in the accretion disk , respectively — so there's no reason they should transition smoothly from one to the other.
pela
<photometry><radio><active-galaxy>
Fitting a line or polynomial to optical and radio SEDs
Jim421616
# Fitting a line or polynomial to optical and radio SEDs

(Asked by: username_0 on 2022-11-10)

I've been trying to fit functions to plots showing photometric data for AGN from both optical and radio measurements, such as:

[![enter image description here](https://i.sstatic.net/SUU4Q.png)](https://i.sstatic.net/SUU4Q.png)

but my supervisor says that this shouldn't be done; the radio and optical components must be treated separately. Why is this?

**Tags:** photometry, radio, active-galaxy

> **Comments:**
> **username_1**: Eyeballing it, it looks like different lines would fit the radio and optical parts...  OB xkcd https://xkcd.com/2048/  
> **username_2**: The two components are caused by two different physical mechanisms — synchrotron radiation from the jet, and the revolving material in the accretion disk , respectively — so there's no reason they should transition smoothly from one to the other.  

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## 0 answers

