Vector with too short arrow

I'm trying to write two vectors like this: Currently I'm using $\vec{p_e,\SI{10}{\hertz},s2}$ bug ig looks like this: How can I write it correctly?

That means:

• long vector arrow
• italic Hz
• Why not \vec{p}_{e,\SI{10}{\hertz},s2}? You can use \overrightarrow to get that exact output, but, at least to me, the arrow is too big. – Manuel Aug 15 '15 at 21:06
• Yeah these are quite long but its the only part in my thesis so its ok. How do I get the italic units? – Hedge Aug 15 '15 at 21:13
• @Hedge The units should always be upright. – egreg Aug 15 '15 at 21:15
• The standard says that units should be typeset upright, I don't see a reason to get the italic version (apart from the fact that that's not italic but math normal font, in the first image). – Manuel Aug 15 '15 at 21:15
• 1) from my perspective (and at least in line with german regulations) the units are UNITS and therefore should NOT be italicized 2) Just write Hz instead of \hertz.. "the challenge" is to get it regular – Bort Aug 15 '15 at 21:16

As far I have understood the math in the question, the vector is p, the remaining part is just an index to the vector. Therefore, a short vector would be sufficient as shown in the following example. I do not know about e, s2, and d7, but 10 Hz is clearly a number with unit, typeset upright, as already shown in the question and correctly done via \SI{10}{\hertz} with the macro \SI from package siunitx.

\vec{p} is replaced by \vec{{}p} as Manuel has suggested in his comment.

The example:

\documentclass{article}

\usepackage{siunitx}

\begin{document}
\dots ors $\vec{{}p}_{e,\SI{10}{\hertz},s2}$
respectively $\vec{{}p}_{e,\SI{10}{\hertz},d7}$
\end{document} • This is a place where \vec{\kern0pt p} or \vec{{}p} is beneficial, in my opinion. – Manuel Aug 16 '15 at 15:57
• @Manuel Thanks, it indeed looks better. Answer updated. – Heiko Oberdiek Aug 16 '15 at 16:03

You might want to give a try to the esvect package, which has 8 nice arrow shapes, loner than the arrow that comes with vec. The base command is \vv, and there is a \vv* command for vectors with indices, in order to have a correct spacing between vector and index:

\documentclass{article}

\usepackage{siunitx}
\usepackage[e]{esvect}

\begin{document}

\dots ors $\vv*{p}{e,\SI{10}{\hertz},s2}$
respectively $\vv*{p}{e,\SI{10}{\hertz},d7}$

\end{document} 