<p>I need help understanding something. In global helioseismology we study the modes directly (stationary waves characterized by 3 integers numbers: <span class="math-container">$n$</span>, <span class="math-container">$l$</span> and <span class="math-container">$m$</span>). As the angular degree <span class="math-container">$l$</span> becomes bigger, the acoustic waves don't form a stationary wave (mode) anymore (they don't have enough lifetime anymore).</p>
<p>But, I'm working with <strong>ring diagram analysis</strong> (one of the techniques of local helioseismology) for these waves that don't form a mode. And in the data we still have and integer number <span class="math-container">$n$</span> (number of nodes in radial direction) and a non-integer number of <span class="math-container">$l$</span> (because the wave is not stationary).</p>
<p>I don't understand, what does that mean?? I have an <span class="math-container">$n$</span> and <span class="math-container">$l$</span> describing a propagating wave? What is the physical mean of that?</p>
<ul>
<li><a href="https://iopscience.iop.org/article/10.1086/306765/fulltext/38895.text.html" rel="noreferrer">https://iopscience.iop.org/article/10.1086/306765/fulltext/38895.text.html</a></li>
<li><a href="https://www2.mps.mpg.de/projects/seismo/NA4/NiceMeeting/proceedings/antia/electronic/ring.pdf" rel="noreferrer">https://www2.mps.mpg.de/projects/seismo/NA4/NiceMeeting/proceedings/antia/electronic/ring.pdf</a></li>
</ul>

CC BY-SA 4.0
2021-03-31T01:17:45.173Z
*Welcome to Astronomy SE!* I've added a bit of formatting and some links that help readers find out what "ring diagram analysis" may mean in this context. It's always good to add whatever you do know to your question so that potential answer authors know where to start.
uhoh
CC BY-SA 4.0
2021-03-31T11:14:44.053Z
I have a similar issue that I never heard of "ring diagrams", so maybe you could please at a quote or two, maybe even a sketch?
B--rian
CC BY-SA 4.0
2021-03-31T15:01:16.597Z
Hello! The ring diagram it's just the technique. We have waves propagating in sun that form stationary waves until some maximum value of angular degree (l). For bigger values we don't wave a mode (stationary wave) anymore. I'm trying to undestand just the physical mean of numbers n and l applied to a propagating wave. It's a wave problem basically
Daniel
<the-sun><plasma-physics><stellar-atmospheres><asteroseismology>
Help understanding ring diagram analysis used in helioseismology
Daniel
# Help understanding ring diagram analysis used in helioseismology

(Asked by: username_0 on 2021-03-31)

I need help understanding something. In global helioseismology we study the modes directly (stationary waves characterized by 3 integers numbers: $n$, $l$ and $m$). As the angular degree $l$ becomes bigger, the acoustic waves don't form a stationary wave (mode) anymore (they don't have enough lifetime anymore).

But, I'm working with **ring diagram analysis** (one of the techniques of local helioseismology) for these waves that don't form a mode. And in the data we still have and integer number $n$ (number of nodes in radial direction) and a non-integer number of $l$ (because the wave is not stationary).

I don't understand, what does that mean?? I have an $n$ and $l$ describing a propagating wave? What is the physical mean of that?

* <https://iopscience.iop.org/article/10.1086/306765/fulltext/38895.text.html>
* <https://www2.mps.mpg.de/projects/seismo/NA4/NiceMeeting/proceedings/antia/electronic/ring.pdf>

**Tags:** the-sun, plasma-physics, stellar-atmospheres, asteroseismology
> **Comments:**
> **username_1**: *Welcome to Astronomy SE!* I've added a bit of formatting and some links that help readers find out what "ring diagram analysis" may mean in this context. It's always good to add whatever you do know to your question so that potential answer authors know where to start.  
> **username_2**: I have a similar issue that I never heard of "ring diagrams", so maybe you could please at a quote or two, maybe even a sketch?  
> **username_0**: Hello! The ring diagram it's just the technique. We have waves propagating in sun that form stationary waves until some maximum value of angular degree (l). For bigger values we don't wave a mode (stationary wave) anymore. I'm trying to undestand just the physical mean of numbers n and l applied to a propagating wave. It's a wave problem basically  

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## 0 answers

