# Changing the spacing inside equation with underbrace [duplicate]

I am aware of questions/answers that address the question of space around the equal-sign (e.g. this one or this other question).
However, my question is related to a situation where I make use of \underbrace:

The text in \underbrace causes a shift to the right of everything outside of the braces.
I do not want to introduce a linebreak in the text, nor do I want to extend the underbrace - I just do not like the large gap in the equation.
I have tried \! without significant effect.
How do I move the portion to the right of the braces so that it is partially above the text?
(Have I missed something in the mathtools package documentation?)

This portion of code reproduces the equation above:

$$\underbrace{\left(\frac{\vec{\omega}\cdot\vec{v}}{\vec{v}\cdot\vec{v}}\right)}_% {\text{projection of }\vec{\omega}\text{ on }\vec{v}}\vec{v}=% \frac{\xi_{\text{s}}}{v_{\text{s}}}\vec{v}$$


## marked as duplicate by Peter Grill, Werner, Jesse, cmhughes, GuidoFeb 7 '14 at 4:42

Try this, using the mathtoolspackage and its \mathclapcommand:

        \documentclass[12pt]{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{lmodern}
\usepackage{mathtools}

\begin{document}%

$$\underbrace{\left(\frac{\vec{\omega}\cdot\vec{v}}{\vec{v}\cdot\vec{v}}\right)}% {\mathclap{\text{projection of }\vec{\omega}\text{ on }\vec{v}}}\vec{v}=% \frac{\xi_{\text{s}}}{v_{\text{s}}}\vec{v}$$

\end{document}


which gives: