# Making hats (and other accents) bold

I've been typesetting some equations, and I've found that the default behavior accents like \hat, \bar, \tilde, etc. makes a rather small and easily-missed mark. Is there some way to make the accents stand out more? In particular, is there any way to make them appear in bold (without affecting the letter they are over)?

Here is one solution, albeit cumbersome:

\documentclass{article}
\usepackage{amsmath}% http://ctan.org/pkg/amsmath
\newcommand{\thickhat}[1]{\mathbf{\hat{\text{$#1$}}}}
\newcommand{\thickbar}[1]{\mathbf{\bar{\text{$#1$}}}}
\newcommand{\thicktilde}[1]{\mathbf{\tilde{\text{$#1$}}}}
\begin{document}
$\hat{a}, \bar{a}, \tilde{a}$ \par
$\hat{\mathbf{a}}, \bar{\mathbf{a}}, \tilde{\mathbf{a}}$ \par
$\mathbf{\hat{a}}, \mathbf{\bar{a}}, \mathbf{\tilde{a}}$ \par
$\thickhat{a}, \thickbar{a}, \thicktilde{a}$ \par
\end{document}


amsmath provides the easy font-and-size switching capability via \text. This allows you to use the \thick-constructs inside super-/subscripts.

• @yrudoy and Werner: This solution doesn't properly place the bold accent. For example, \thickhat{A} doesn't yield the desired output. – Hendrik Vogt Aug 12 '12 at 20:03

bm package can help here.

The first row is normal, the second is normal with bold accents and the third is all bold.

\documentclass{article}

\usepackage{bm}

\begin{document}

\showoutput

$\hat{a }\bar{a} \tilde{a}$

$\bm\hat{a} \bm\bar{a} \bm\tilde{a}$

$\bm{\hat{a}} \bm{\bar{a}} \bm{\tilde{a}}$

\end{document}

• How to define a new command which can do that ?. I tried \renewcommand\bar{\bm\bar}, but it does not work. – Mohamed Vall May 3 '16 at 6:03
• @LlavDem that defines \bar to be an infinite loop. just use \newcommand\boldbar{\bm\bar} (or use \bmdefine) – David Carlisle May 3 '16 at 8:05
• Using \bm\bar{\mathbb{R}} does not seem to work (with, say, amsfonts loaded so as to produce the blackboard bold letter). – murray Aug 6 '16 at 14:52
• @murray I just added $\bm\hat{\mathbb{R}}$ to the above and changed the preamble to \documentclass{article} \usepackage{amsfonts} \usepackage{bm} \begin{document} and it worked fro me – David Carlisle Aug 6 '16 at 14:59
• @David Carlisle: You're correct. Not sure what I did that originally didn't make it work for me. – murray Aug 7 '16 at 0:18