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\begin{document}  
%%%%%%%%%%%%%%%% Pre-defined commands, you can use for the most obvious notations
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%\newcommand{\gevsq}{\mathrm{GeV}^2}
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% Journal macro
\def\Journal#1#2#3#4{{#1} {\bf #2} (#3) #4}
\def\NCA{\em Nuovo Cimento}
\def\NIM{\em Nucl. Instrum. Methods}
\def\NIMA{{\em Nucl. Instrum. Methods} {\bf A}}
\def\NPB{{\em Nucl. Phys.}   {\bf B}}
\def\PLB{{\em Phys. Lett.}   {\bf B}}
\def\PRL{\em Phys. Rev. Lett.}
\def\PRD{{\em Phys. Rev.}    {\bf D}}
\def\ZPC{{\em Z. Phys.}      {\bf C}}
\def\EJC{{\em Eur. Phys. J.} {\bf C}}
\def\CPC{\em Comp. Phys. Commun.}

\begin{titlepage}

\noindent
%\begin{flushleft}
%{\tt DESY YY-NNN    \hfill    ISSN 0418-9833} \\
%{\tt Month YYYY}                  \\
%\end{flushleft}



\noindent
%Date:          [today  instruction is preferred] \\ %\today      \\
%Version:       Preparatives 0.1,0.2...; 1st draft: 1.0, 1.1...; 2nd Draft 2.0..., Final Reading 3.0,3.1...      \\
%Editors:            \\
%Referees:           \\
%Comments by         \\
\noindent
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%% For conference papers  %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%% coment the header and fill the right conference
%%%%% {\it {\large version of \today}} \\[.3em]
\begin{center} %%% you may want to use this line for working versions
 \begin{small}
 \begin{tabular}{llrr}
 {\bf H1prelim-10-017} Submitted to & & &
 \epsfig{file=H1logo_bw_small.epsi
 ,width=1.5cm} \\[.2em] \hline
 \multicolumn{4}{l}{{\bf
                  XVIII International Workshop on Deep Inelastic Scattering, 
		  DIS2010},
                  April 19-23,~2010,~Florence} \\
%                  Abstract:        & {\bf xx-xxx}    & & \\
%                  Parallel Session & {\bf x}   & & \\ \hline
                  Parallel Session & {\bf Small-x, diffraction and VM in DIS and hadron colliders}   & & \\ \hline
   \multicolumn{4}{l}{\footnotesize {\it Electronic Access:
  www-h1.desy.de/publications/H1preliminary.short\_list.html}} \\[.2em]
 \end{tabular}
 \end{small}
 \end{center}


\vspace{2cm}
\begin{center}
\begin{Large}

{\bf Measurement of the longitudinal diffractive structure function $F_L^D$ at low $Q^2$ at HERA}
%\\(version of \today )}

\vspace{2cm}

H1 Collaboration

\end{Large}
\end{center}

\vspace{2cm}

\begin{abstract}
A measurement of the longitudinal diffractive structure function 
$F_L^D$ at low $Q^2$ using the H1 detector at HERA is presented.
Measurements of the diffractive cross-section
at centre of mass energies $\sqrt{s}$ of 225 and 252 GeV
in the $Q^2$ range of $[2.5; 7]$~GeV$^2$, using HERA data taken in 2007,
are combined
with a published measurement at $\sqrt{s}$ of 300 GeV.
The structure function $F_L^D$ is extracted from these cross-sections
at high values of inelasticity $y$.
%The measured $F_L^D$
%is compared to predictions from NLO QCD fits to the data at $\sqrt{s}$ of 300 GeV.
%Only data at $Q^2 > 8.5$~GeV$^2$ was considered in the fit,
%therefore the predictions are only exptrapolations to lower $Q^2$.
The measured values of $F_L^D$ are compared with extrapolations of NLO QCD fits to published data,
where the fits only included data with $Q^2 > 8.5$~GeV$^2$. 
\end{abstract}

\vspace{1.5cm}

%\begin{center}
%To be submitted to \EJC \;\; or \PLB
%\end{center}

\end{titlepage}

%          THE PAPER DRAFTS HAVE NO AUTHORLIST
%
%          FOR PAPER ISSUED FOR THE FINAL READING 
%          COPY THE AUTHOR AND INSTITUTE LISTS 
%          INTO YOUR AREA
%
% from /h1/iww/ipublications/h1auts.tex 
%          AND UNCOMMENT THE NEXT THREE LINES 
%
%\begin{flushleft}
%  \input{h1auts}
%\end{flushleft}
%
% Please not that the author list may need re-formatting.

\newpage


\begin{figure}
\begin{center}
%\includegraphics[width=1.0\columnwidth]{./preliminaryeps/cp460.eps}
\includegraphics[width=1.0\columnwidth]{./figures/H1prelim-10-017.fig1.eps}
\caption{The electron energy, $log(Q^2)$, $y_e$, the summed $E-p_z$ of
  all final state particles, $\beta$ and $\xpom$ distributions for the
  $E_p=460\;{\rm GeV}$ data.
  For $y_e > 0.6$, there is a requirement of positive charge of
  the scattered lepton candidate. Negatively charged data events (green)
  are used to determine the amount of photoproduction background
  in the region of $y_e > 0.6$.
  Data (points) is compared with the sum of diffractive DIS Monte Carlo
  (red histogram) and negatively charged events. }
\end{center}
\end{figure}

\newpage

\begin{figure}
\begin{center}
%\includegraphics[width=1.0\columnwidth]{./preliminaryeps/cp575.eps}
\includegraphics[width=1.0\columnwidth]{./figures/H1prelim-10-017.fig2.eps}
\caption{The electron energy, $log(Q^2)$, $y_e$, the summed $E-p_z$ of
  all final state particles, $\beta$ and $\xpom$ distributions for the
  $E_p=575\;{\rm GeV}$ data.
  For $y_e > 0.5$, there is a requirement of positive charge of
  the scattered lepton candidate. Negatively charged data events (green)
  are used to determine the amount of photoproduction background
  in the region of $y_e > 0.5$.
  Data (points) is compared with the sum of diffractive DIS Monte Carlo
  (red histogram) and negatively charged events. }
\end{center}
\end{figure}

\newpage

\begin{figure}
\begin{center}
%\includegraphics[width=0.6\columnwidth]{./preliminaryeps/x920.eps}
\includegraphics[width=0.6\columnwidth]{./figures/H1prelim-10-017.fig3.eps}
\caption{Previous measurement of the reduced cross-section at $E_p=820\; {\rm
    GeV}$.
  The published cross-sections are recalculated at the $\xpom$, $Q^2$ and $\beta$
  values chosen for the low $Q^2$ $F_L^D$ measurement. 
  The data are compared to the H1~2006~DPDF~Fit~B
  which use the same data set starting at $Q^2$ of 8.5 GeV$^2$.
  The fit is extrapolated to $Q^2 = 4$~GeV$^2$
  where it is known to underestimate the diffractive cross-section. 
  Also shown is the prediction for $F_2^D$
  from the same fit.  The inner error bars are statistical, outer
  error bars show the statistical and systematic errors added in
  quadrature.}
\end{center}
\end{figure}

\newpage

\begin{figure}
\begin{center}
%\includegraphics[width=0.6\columnwidth]{./preliminaryeps/x460.eps}
\includegraphics[width=0.6\columnwidth]{./figures/H1prelim-10-017.fig4.eps}
\caption{Measurement of the reduced cross-section at $E_p=460\; {\rm
    GeV}$.  The data are compared to a low $Q^2$ extrapolation of an NLO QCD fit to previous H1
  data, H1~2006~DPDF~Fit~B,
  which use data starting at $Q^2$ of 8.5 GeV$^2$.
  The fit is extrapolated to $Q^2 = 4$~GeV$^2$
  where it is known to underestimate the diffractive cross-section. 
  %The fit is known to start under-estimating the diffractive cross-sections at $Q^2$ around 10~GeV$^2$.
  Also shown is the prediction for $F_2^D$
  from the same fit.  The inner error bars are statistical, outer
  error bars show the statistical and systematic errors added in
  quadrature.}
\end{center}
\end{figure}

\newpage

\begin{figure}
\begin{center}
%\includegraphics[width=0.6\columnwidth]{./preliminaryeps/x575.eps}
\includegraphics[width=0.6\columnwidth]{./figures/H1prelim-10-017.fig5.eps}
\caption{Measurement of the reduced cross-section at $E_p=575\; {\rm
    GeV}$.  The data are compared to a low $Q^2$ extrapolation of an NLO QCD fit to previous H1
  data, H1~2006~DPDF~Fit~B,
  which use data starting at $Q^2$ of 8.5 GeV$^2$.
  The fit is extrapolated to $Q^2 = 4$~GeV$^2$
  where it is known to underestimate the diffractive cross-section. 
  %The fit is known to start under-estimating the diffractive cross-sections at $Q^2$ around 10~GeV$^2$.
  Also shown is the prediction for $F_2^D$
  from the same fit.  The inner error bars are statistical, outer
  error bars show the statistical and systematic errors added in
  quadrature.}
\end{center}
\end{figure}

\newpage

\begin{figure}
\begin{center}
%\includegraphics[width=0.6\columnwidth]{./preliminaryeps/xall.eps}
\includegraphics[width=0.6\columnwidth]{./figures/H1prelim-10-017.fig6.eps}
\caption{New measurement of the reduced cross-section at $E_p=460, 575$~GeV,
  together with the combination of previously published cross sections at $E_p=820$~GeV.
  The data are compared to a low $Q^2$ extrapolation of an NLO QCD fit to the
  H1 data at $E_p=820$~GeV, H1~2006~DPDF~Fit~B,
  which use data starting at $Q^2$ of 8.5 GeV$^2$.
  The fit is extrapolated to $Q^2 = 4$~GeV$^2$
  where it is known to underestimate the diffractive cross-section. 
  Also shown is the prediction
  for $F_2^D$ from the same fit.  The inner error bars are
  statistical, outer error bars show the statistical and systematic
  errors added in quadrature.}
\end{center}
\end{figure}

\newpage

\begin{figure}[p]
\begin{center}
%\includegraphics[width=.45\columnwidth]{./preliminaryeps/fit4.eps}
%\includegraphics[width=.45\columnwidth]{./preliminaryeps/fit3.eps}
\includegraphics[width=.45\columnwidth]{./figures/H1prelim-10-017.fig7a.eps}
\includegraphics[width=.45\columnwidth]{./figures/H1prelim-10-017.fig7b.eps}
\caption{The reduced cross-section measured at $Q^2=4\; GeV^2$ and
  different bins of $\beta$ as a function of $y^2 / [(1+(1-y)^2)]$ for
  $E_p=460$ (red squares), $E_p=575$ (blue triangles) and $E_p=820$
  (black circles) GeV are shown.  The inner error bars are statistical, outer
  error bars show the statistical and systematic errors added in
  quadrature.  The straight lines show the linear fits use to
  determine $F_L^D$.}
\end{center}
\end{figure}

\newpage

\begin{figure}
\begin{center}
%\includegraphics[width=0.6\columnwidth]{./preliminaryeps/fld.0.eps}
\includegraphics[width=0.6\columnwidth]{./figures/H1prelim-10-017.fig8.eps}
\caption{The diffractive longitudinal structure function $F_L^D$
  multiplied by $\xpom$, measured in the $Q^2$ range of $[2.5; 7]$~GeV$^2$ and
  $\xpom$ of $[0.001; 0.01]$.  The data are compared to predictions from
  two NLO QCD fits to previous H1 data, H1 2006 DPDF Fit A (blue line)
  and Fit B (red line).
  Also shown is the value of $F_2^D$ as a dotted red line.
  The fits use data starting at $Q^2$ of 8.5 GeV$^2$.
  Here, they are extrapolated to $Q^2 = 4$~GeV$^2$
  where they are known to underestimate the diffractive cross-section.
  The data are consistent with the extrapolated fit.} 
  %The fits are known to start under-estimating the diffractive cross-sections at $Q^2$ around 10~GeV$^2$.}
\end{center}
\end{figure}

\newpage

\begin{figure}
\begin{center}
%\includegraphics[width=0.6\columnwidth]{./preliminaryeps/fldtshirt2.eps}
\includegraphics[width=0.6\columnwidth]{./figures/H1prelim-10-017.fig9.eps}
\caption{The diffractive longitudinal structure function $F_L^D$
  multiplied by $\xpom$.
  The new measurement at $Q^2 = 4$~GeV$^2$ is shown together with
  the first measurement of $F_L^D$, performed by the H1 Collaboration at $Q^2 = 13.5$~GeV$^2$.
  The data are compared to predictions from
  two NLO QCD fits to previous H1 data, H1 2006 DPDF Fit A (blue line)
  and Fit B (red line).
  The fits use data starting at $Q^2$ of 8.5 GeV$^2$.
  They are extrapolated to $Q^2 = 4$~GeV$^2$ (dotted lines)
  where they are known to underestimate the diffractive cross-section. 
  %The predictions for $Q^2 = 4$~GeV$^2$ are plotted as dotted lines
  %since these are extrapolations to low $Q^2$ of the fits.
  The data are consistent with both predictions at $Q^2 = 13.5$~GeV$^2$,
  and their extrapolations to $Q^2 = 4$~GeV$^2$.} 
\end{center}
\end{figure}

\end{document}
