TeX - LaTeX Stack Exchange is a question and answer site for users of TeX, LaTeX, ConTeXt, and related typesetting systems. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Throughout Neukirch's Algebraic Number Theory, he denotes Dedekind domains and their extension respectively with a small and a large version of what I can only describe as a thinner (i.e., less bolded) $\mathcal{O}$, which is commonly used symbol to denote the ring of integers of a number field.

enter image description here

Here is a usage in the book where it is side by side with the standard $\mathcal{O}$:

enter image description here

How can I reproduce these symbols? They don't appear to be in the standard alphabets (like \mathcal, \mathfrak, etc.).

share|improve this question
On TeX.SE, visualization of TeX is usually done through an image upload, rather than a rendering via MathJax, say. I've removed that from your post since most people know this. See Why doesn't maths render as maths? – Werner Jun 25 '12 at 0:49
For symbol lookup or identification, see How to look up a symbol? Are you able to find your symbol using any of the methods described in the linked post? Give some feedback. – Werner Jun 25 '12 at 0:52
@Werner: No, it's not in the "Comprehensive LaTeX symbols" link and detexify-ing just gave me $\mathcal{O}$. – JSeaton Jun 25 '12 at 1:07
@Werner: is there a place where I can see the alphabet rendered into the different math fonts? I'm willing to be that this is symbol is just the letter 'o' in some particular math font. – JSeaton Jun 25 '12 at 1:09
See the mathalfa package (ctan.org/tex-archive/macros/latex/contrib/mathalfa) for an overview of math alphabets. – Mico Jun 25 '12 at 1:37
up vote 4 down vote accepted

This looks like a resized \mathcal{O} to \scriptsize:

enter image description here

\noindent \textbf{(8.1) Proposition.} \slshape Let~\dedekind\ be a Dedekind domain
with field of fractions~$K$, let $L|K$ be a finite extension of~$K$ and~$\mathcal{O}$
the integral closure of~\dedekind\ in~$L$. Then~$\mathcal{O}$ is again a Dedekind

Depending on the usage (commonly standalone or part of math expressions), the following definition might be of benefit:


\ensuremath allows you to intermix the usage within math and text mode. A more extensive definition of \dedekind would include \mathchoice to allow for resizing of \mathcal{O} "dynamically" if used in superscript.

share|improve this answer
Thank you for the great response. – JSeaton Jun 25 '12 at 3:20
It's also nice to see more examples of where ties are supposed to be used. I can never figure it out myself. – Ryan Reich Jun 25 '12 at 4:11

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.