<A NAME=MSHELL>
<TITLE>MSHELL</TITLE></A>
<b><a href=r37_idx.html>INDEX</a></b><p><p>
<B>MSHELL</B> _ _ _ _ _ _ _ _ _ _ _ _ <B>command</B><P>
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The <em>mshell</em> command puts particles on the mass shell in high-energy
physics calculations.
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syntax: </H3>
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<em>mshell</em><vector-var>{,<vector-var>}*
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<vector-var> must have had a mass attached to it by a
<A HREF=r37_0413.html>mass</A>
declaration.
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examples: </H3>
<P><PRE><TT>
vector v1,v2;
mass v1=m,v2=q;
mshell v1;
v1.v1;
2
M
v2.v2;
V2.V2
mshell v2;
v1.v1*v2.v2;
2 2
M *Q
</TT></PRE><P>Even though a mass is attached to a vector variable representing a
particle, the replacement does not take place until the <em>mshell</em>
declaration is given for that vector variable.
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