efault = <strong>off</strong></code>)<br/>
several existing <a href="Tunes.html" target="page">tunes</a> do not include CD. 
An inclusion of a nonvanishing CD cross section directly affects 
the nondiffractive phenomenology (even if not dramatically), and so
this flag is used to switch off the CD cross section in such tunes.
You can switch it back on <i>after</i> the selection of a tune, if you
so wish. This option has no effect for the MBR model 
(<code>Diffraction:PomFlux = 5</code>), where the CD cross s