%
%  Discuss systematic uncertainties that are common
%
%  Revisions:
%
%   13 Jul 05    PKS    Original version
%   13 Jul 05    EMB    Complete and add plots
%   16 Jul 05    PKS    Tidy up and incorporate 1st draft comments
%   20 Jul 05    PKS    Incorporate second draft comments.
%   21 Jul 05    PKS    Compress even further.
%   30 Aug 05    PKS    Implement Draft 2 changes.
%

There are a number of additional systematic uncertainties that 
affect both analyses:
initial state and final state radiation uncertainties (ISR/FSR);
%affect the extra jet activity in \ttbar events and
%modify the jet kinematics; 
uncertainties arising from the parton distribution functions (PDFs); 
and uncertainties arising from $b$-jet fragmentation, decays, and
color connections, modeling of the background processes, and 
the event generators we employ (Modeling).
\Tab{t:uncertainties} summarizes these uncertainties. 

\begin{table}
\caption[Systematic uncertainty summary.]
{The systematic uncertainties for the
two analyses.}
\label{t:uncertainties}
\begin{ruledtabular}
\begin{tabular}{ldd}
Systematic &
\multicolumn{1}{c}{DLM} &
\multicolumn{1}{c}{Template} \\
&
\multicolumn{1}{c}{$\Delta\mtop$ (\gevccnoarg)} &
\multicolumn{1}{c}{$\Delta\mtop$ (\gevccnoarg)} \\
\hline
Jet Energy Scale& 3.0 &
\multicolumn{1}{c}{$[\sim 2.5]$\footnotemark[1]} \\
ISR/FSR         & 0.6 & 0.7 \\
PDFs            & 0.5 & 0.3 \\
Modeling        & 0.8 & 0.9 \\
Method          & 0.5 & 0.6 \\
\hline
Total 			    & 3.2 & 1.3\footnotemark[1]
\footnotetext[1]{\label{f:systtable}The \jes systematic
is included in the uncertainty reported by the likelihood fit.}
\end{tabular}
\end{ruledtabular}
\end{table}

%  Discuss DLM systematics, derive final measurement
%
The DLM method has additional uncertainties that arise from the
use of transfer functions and from the procedure that corrects the
measured mass for the presence of background (Method).
Together with the \jes and other common sources noted above, the systematic
uncertainty on the DLM mass measurement is \gevcc{3.2}.
%  Discuss Template systematics, derive final measurement
%
The template method has additional uncertainties arising from the 
statistical precision of the templates themselves and approximations
made in treating \jes as a single parameter affecting 
all jets coherently (Method).
%These uncertainties, combined in quadrature, are \gevcc{1.3}.  
Excluding \jes, the total systematic uncertainty on the
template mass measurement is \gevcc{1.3}.
