%% hepunits
%%   High energy physics (HEP) extensions to the SIunits package
%% Author: Andy Buckley <andy@insectnation.org>
%%
%% This material is subject to the LaTeX Project Public License.
%% See http://www.ctan.org/tex-archive/help/Catalogue/licenses.lppl.html
%% or the details of that license.
%%
%% Please let me know if you use hepunits and what you think of it.
%% I'll try to implement any suggested options that seem sensible!

\def\fileversion{2.0.0}
\def\filedate{2020/04/10}
\NeedsTeXFormat{LaTeX2e}
\ProvidesPackage{hepunits}[\filedate\space High-energy physics units by Andy Buckley (v\fileversion)]


%% Option handling
\def\@yes{yes}
\def\@HEPopt@noprefixcmds{}
\def\@HEPopt@sicmds{}
\def\@HEPopt@freestanding{}
\DeclareOption{sicmds}{\def\@HEPopt@sicmds{yes}}
\DeclareOption{noprefixcmds}{\def\@HEPopt@noprefixcmds{yes}}
\DeclareOption{freestanding}{\def\@HEPopt@freestanding{yes}}
\ProcessOptions
\ifx\@HEPopt@noprefixcmds\@yes\def\@HEPopt@sicmds\@empty\fi


%% Get the dependency packages
\RequirePackage{amsmath}
\RequirePackage{ifthen}
\RequirePackage{siunitx}

%% Pass default config to siunitx
\sisetup{detect-all, detect-display-math, mode=text}
\ifx\@HEPopt@freestanding\@yes
\sisetup{free-standing-units=true}
\fi


%% -------------------------------------------------
%% Units defined below here
%% -------------------------------------------------

\DeclareSIUnit{\Hz}{\hertz}

\ifx\@HEPopt@sicmds\@yes
%% Lengths
\DeclareSIUnit{\fermi}{\femto\metre}
\DeclareSIUnit{\nm}{\nano\metre}
\DeclareSIUnit{\micron}{\micro\metre}
\DeclareSIUnit{\um}{\micro\metre}
\DeclareSIUnit{\mm}{\milli\metre}
\DeclareSIUnit{\cm}{\centi\metre}

%% Angles
\DeclareSIUnit{\mrad}{\milli\radian}

%% Times
\DeclareSIUnit{\as}{\atto\second}
\DeclareSIUnit{\fs}{\femto\second}
\DeclareSIUnit{\ps}{\pico\second}
\DeclareSIUnit{\ns}{\nano\second}

%% Rates
\DeclareSIUnit{\mHz}{\milli\hertz}
\DeclareSIUnit{\kHz}{\kilo\hertz}
\DeclareSIUnit{\MHz}{\mega\hertz}
\DeclareSIUnit{\GHz}{\giga\hertz}
\DeclareSIUnit{\THz}{\tera\hertz}
\fi


%% Fields
\DeclareSIUnit{\gauss}{G}

%% Luminosity
\DeclareSIUnit{\invcmsq}{\centi\metre\tothe{-2}}
\DeclareSIUnit{\invcmsqpersecond}{\invcmsq\second\tothe{-1}}
\DeclareSIUnit{\invcmsqpersec}{\invcmsqpersecond}

%% (Inverse) cross-sections
\DeclareSIUnit{\invbarn}{\barn\tothe{-1}}
\ifx\@HEPopt@noprefixcmds\@empty
\DeclareSIUnit{\millibarn}{\milli\barn}
\DeclareSIUnit{\microbarn}{\micro\barn}
\DeclareSIUnit{\nanobarn}{\nano\barn}
\DeclareSIUnit{\picobarn}{\pico\barn}
\DeclareSIUnit{\femtobarn}{\femto\barn}
\DeclareSIUnit{\attobarn}{\atto\barn}
\DeclareSIUnit{\zeptobarn}{\zepto\barn}
\DeclareSIUnit{\yoctobarn}{\yocto\barn}
\DeclareSIUnit{\invnanobarn}{\nano\invbarn}
\DeclareSIUnit{\invpicobarn}{\pico\invbarn}
\DeclareSIUnit{\invfemtobarn}{\femto\invbarn}
\DeclareSIUnit{\invattobarn}{\atto\invbarn}
\DeclareSIUnit{\invzeptobarn}{\zepto\invbarn}
\DeclareSIUnit{\invyoctobarn}{\yocto\invbarn}
\DeclareSIUnit{\invnb}{\invnanobarn}
\DeclareSIUnit{\invpb}{\invpicobarn}
\DeclareSIUnit{\invfb}{\invfemtobarn}
\DeclareSIUnit{\invab}{\invattobarn}
\DeclareSIUnit{\invzb}{\invzeptobarn}
\DeclareSIUnit{\invyb}{\invyoctobarn}
\fi

%% HEP energy, momentum and mass units
% \DeclareSIUnit{\electronvolt}{\text{e\kern-1.2\scriptspace V}}
\DeclareSIUnit{\electronvolt}{\text{e\kern-0.15ex V}}
\DeclareSIUnit{\eV}{\electronvolt}
\newcommand{\@eVoverc}[1][]{\ensuremath{
    \eV
    \ifthenelse{\equal{\f@series}{\bfdefault}}{/}{\mkern-\medmuskip/\mkern-\thinmuskip}
    \text{\ensuremath{c#1}}
  }}
\DeclareSIUnit{\electronvoltc}{\@eVoverc}
\DeclareSIUnit{\electronvoltcsq}{\@eVoverc[^2]}
\DeclareSIUnit{\eVc}{\@eVoverc}
\DeclareSIUnit{\eVcsq}{\@eVoverc[^2]}
\ifx\@HEPopt@noprefixcmds\@empty
\DeclareSIUnit{\meV}{\milli\eV}
\DeclareSIUnit{\keV}{\kilo\eV}
\DeclareSIUnit{\MeV}{\mega\eV}
\DeclareSIUnit{\GeV}{\giga\eV}
\DeclareSIUnit{\TeV}{\tera\eV}
\DeclareSIUnit{\meVc}{\milli\eVc}
\DeclareSIUnit{\keVc}{\kilo\eVc}
\DeclareSIUnit{\MeVc}{\mega\eVc}
\DeclareSIUnit{\GeVc}{\giga\eVc}
\DeclareSIUnit{\TeVc}{\tera\eVc}
\DeclareSIUnit{\meVcsq}{\milli\eVcsq}
\DeclareSIUnit{\keVcsq}{\kilo\eVcsq}
\DeclareSIUnit{\MeVcsq}{\mega\eVcsq}
\DeclareSIUnit{\GeVcsq}{\giga\eVcsq}
\DeclareSIUnit{\TeVcsq}{\tera\eVcsq}
\fi