Principles of the Particle Entity Notation (PEN)

Starting at the left, a name is built from the following characters:

1. Start the entity with a recognized string (in the following this was chosen as uppercase P). This is necessary to uniquely identify entities as following the PEN convention.
2. The following letters act as an escape to signal a special interpretation of the string. Present escape sequences are:
   • a for anti particle (normally visually represented with a bar over the particle's name)
   • b for bottom particle
   • c for charmed particle
   • g for indicating the subsequent letter is Greek. The correspondence between Latin and Greek letters is based on the notation for mathematical Greek characters used by the AAP mathematical formula application[5]:

     <!NOTATION greek2 PUBLIC "+//ISBN 1-880124::NISO//NOTATION GREEK-2//EN">

     This one-letter correspondence is as follows:

     Greek name code Greek name code Greek name code Greek name code

     alpha a A Alpha A beta b B Beta B

     gamma g Gamma G delta d Delta D

     epsilon e E Epsilon E zeta z Z Zeta Z

     eta h H Eta H theta q Theta Q

     iota i I Iota I kappa k K Kappa K

     lambda l Lambda L mu m M Mu M

     nu n N Nu N xi x Xi X

     o omicron o O Omicron O pi p Pi P

     rho r R Rho R sigma s Sigma S

     tau t T Tau T upsilon u Upsilon U

     phi f Phi F chi c X Chi C

     psi y Psi Y omega w Omega W

   • q for quark particle
   • s for strange particle
   • S for supersymmetric particle
   • t for top particle
3. The one-letter name of the particle
4. Optionally followed by other information
   • z for zero, i for one, ii for two, iii for three, iv for four
   • m for minus, p for plus, pm for plus/minus
   • pr for prime
   • st for asterisk (star)
   • L for left handed, R for right handed
   • any one-letter particle name