e origin. It is also 
possible to shift the above distributions to be centered around another
nominal position. You must have <code>Beams:allowVertexSpread = on</code>
to use this possibility.

<p/><code>parm&nbsp; </code><strong> Beams:offsetVertexX &nbsp;</strong> 
 (<code>default = <strong>0.</strong></code>)<br/>
The <i>x</i> location of the interaction vertex is centered at this value. 
  

<p/><code>parm&nbsp; </code><strong> Beams:offsetVertexY &nbsp;</strong> 
 (<code>default = <strong>0.</strong></