g makefile 
<code>Makefile_modelname_N</code>. This main program links in the 
process classes in the process directory described above. To run the 
example main program, just go to the <code>examples/</code> 
directory and run 
<br/><code>make -f Makefile_modelname_N</code> 
<br/>or run <code>launch</code> directly inside the MadGraph 5
command line interface.</li>
</ul>

<p/>
Note that in order for PYTHIA 8 to be able to automatically decay any
new particles, it is necessary to specify the branching ratio