# [NTG-context] how to make a \lambdabar (like \hbar)

Sanjoy Mahajan sanjoy at MIT.EDU
Mon Mar 10 11:15:42 CET 2014

\hbar is used a lot in physics.  Once in a while, one also uses
\lambdabar to mean \lambda/2\pi.  It's Unicode description is 'LATIN
SMALL LETTER LAMBDA WITH STROKE' (U+019B).

I've been using this hack

\def\lambdabar{\lambda\kern-1ex\raise0.65ex\hbox{-}}

But it's not beautiful.  Is there a better way to get a lambdabar
into (or from) the math fonts?  I tried

\def\lambdabar                    {\Umathchar  "0"0"00019B }

by analogy with the definition of \hbar in luatex-math.tex, but it
produces a blank space.  There must be no entry for it in the regular
(or Palatino) math fonts.