%================================================================ \documentclass[12pt]{article} \usepackage{epsfig} \usepackage{amsmath} \usepackage{hhline} \usepackage{amssymb} \usepackage{times} \usepackage{cite} \renewcommand{\topfraction}{1.0} \renewcommand{\bottomfraction}{1.0} \renewcommand{\textfraction}{0.0} \newlength{\dinwidth} \newlength{\dinmargin} \setlength{\dinwidth}{21.0cm} \textheight23.5cm \textwidth16.0cm \setlength{\dinmargin}{\dinwidth} \setlength{\unitlength}{1mm} \addtolength{\dinmargin}{-\textwidth} \setlength{\dinmargin}{0.5\dinmargin} \oddsidemargin -1.0in \addtolength{\oddsidemargin}{\dinmargin} \setlength{\evensidemargin}{\oddsidemargin} \setlength{\marginparwidth}{0.9\dinmargin} \marginparsep 8pt \marginparpush 5pt \topmargin -42pt \headheight 12pt \headsep 30pt \footskip 24pt \parskip 3mm plus 2mm minus 2mm %===============================title page============================= \begin{document} % The rest % ------------------------------------------------------------------------- % \documentstyle[12pt,epsfig,cite]{article} % \pagestyle{plain} % \markright{} % \textheight 23.0cm % \textwidth 16.0cm % \topmargin -1.0cm % \oddsidemargin 0.0cm % \newcommand{\scaption}[1]{\caption{\protect{\footnotesize #1}}} \newcommand{\proc}[2]{\mbox{$ #1 \rightarrow #2 $}} \newcommand{\average}[1]{\mbox{$ \langle #1 \rangle $}} \newcommand{\av}[1]{\mbox{$ \langle #1 \rangle $}} \newcommand{\lsim}{\raisebox{-0.5mm}{$\stackrel{<}{\scriptstyle{\sim}}$}} \newcommand{\gsim}{\raisebox{-0.5mm}{$\stackrel{>}{\scriptstyle{\sim}}$}} % variables \newcommand{\gsp}{\mbox{$\gamma^* p$}} \newcommand{\gsel}{\mbox{$\gamma^* p \rightarrow \rho p$}} \newcommand{\gspd}{\mbox{$\gamma^* p \rightarrow \rho Y$}} \newcommand{\PO}{{\sl l \! P }} \newcommand{\ro}{\mbox{$\rho$}} \newcommand{\roo}{\mbox{$\rho^0$}} \newcommand{\rh}{\mbox{$\rho$}} \newcommand{\rhz}{\mbox{$\rh^0$}} \newcommand{\ph}{\mbox{$\phi$}} \newcommand{\om}{\mbox{$\omega$}} \newcommand{\jpsi}{\mbox{$J/\psi$}} \newcommand{\Qsq}{\mbox{$Q^2$}} \newcommand{\qsq}{\mbox{$Q^2$}} \newcommand{\W}{\mbox{$W$}} \newcommand{\x}{\mbox{$x$}} \newcommand{\y}{\mbox{$y$}} \newcommand{\pts}{\mbox{$P_t^2$}} \newcommand{\tpr}{\mbox{$t\,'$}} \newcommand{\ttr}{\mbox{$t$}} \newcommand{\ttra}{\mbox{$t$}} \newcommand{\s}{\mbox{$s$}} \newcommand{\R}{\mbox{$R$}} \newcommand{\bslope}{\mbox{$b$}} \newcommand{\bsl}{\mbox{$b$}} \newcommand{\eclmax}{\mbox{$E_{max}$}} \newcommand{\mpipi}{\mbox{$M_{\pi^+\pi^-}$}} \newcommand{\mkk}{\mbox{$M_{K^+K^-}$}} \newcommand{\mll}{\mbox{$m_{l^+l^-}$}} \newcommand{\mpp}{\mbox{$m_{\pi\pi}$}} % for use in B_W \newcommand{\mppsq}{\mbox{$m_{\pi\pi}^2$}} % for use in B_W \newcommand{\mpi}{\mbox{$m_{\pi}$}} % for use in B_W \newcommand{\mrho}{\mbox{$m_{\rho}$}} % for use in B_W \newcommand{\mrhosq}{\mbox{$m_{\rho}^2$}} % for use in B_W \newcommand{\Gmpp}{\mbox{$\Gamma (\mpp)$}} % for use in B_W \newcommand{\Gmppsq}{\mbox{$\Gamma^2(\mpp)$}} % for use in B_W \newcommand{\Grho}{\mbox{$\Gamma_{\rho}$}} % for use in B_W \newcommand{\gp}{\mbox{$\gamma p$}} \newcommand{\modt}{\mbox{$|t|$}} \newcommand{\eminpz}{\mbox{$E-p_z$}} \newcommand{\costhst}{\mbox{$\cos\theta^*$}} \newcommand{\rzzzz}{\mbox{$r_{00}^{04}$}} \newcommand{\rzero}{\mbox{$r_{00}^{04}$}} \newcommand{\llq}{$\alpha_s \ln{(\qsq / \Lambda_{QCD}^2)}$} \newcommand{\llqx}{$\alpha_s \ln{(\qsq / \Lambda_{QCD}^2)} \ln{(1/x)}$} \newcommand{\llx}{$\alpha_s \ln{(1/x)}$} \newcommand{\zin}{\mbox{${\rm z_\Psi}$}} \newcommand{\Brodsky}{Brodsky {\it et al.}} \newcommand{\FKS}{Frankfurt, Koepf and Strikman} \newcommand{\Kop}{Kopeliovich {\it et al.}} \newcommand{\Ginzburg}{Ginzburg {\it et al.}} \newcommand{\Ryskin}{\mbox{Ryskin}} \newcommand{\Kaidalov}{Kaidalov {\it et al.}} % units \newcommand{\gev}{\mbox{\rm GeV}} \newcommand{\gevc}{\mbox{\rm GeV}} \newcommand{\Gevc}{\mbox{\rm GeV}} \newcommand{\GeV}{\mbox{\rm GeV}} \newcommand{\geVx}{\rm GeV} \newcommand{\GeVsq}{\mbox{${\rm GeV}^2$}} \newcommand{\gevsq}{\mbox{${\rm GeV}^2$}} \newcommand{\gevsqc}{\mbox{${\rm GeV^2}$}} \newcommand{\gevcsq}{\mbox{${\rm GeV}$}} \newcommand{\Gevcc}{\mbox{${\rm GeV}$}} \newcommand{\mevcsq}{\mbox{${\rm MeV}$}} \newcommand{\Gevsqm}{\mbox{${\rm GeV}^{-2}$}} \newcommand{\GeVsqm}{\mbox{${\rm GeV}^{-2}$}} \newcommand{\gevsqm}{\mbox{${\rm GeV}^{-2}$}} \newcommand{\nbinv}{\mbox{${\rm nb^{-1}}$}} \newcommand{\pbinv}{\mbox{${\rm pb^{-1}}$}} % % 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.} % journals \def\ar#1#2#3 {{\em Ann. Rev. Nucl. Part. Sci.} {\bf#1} (#2) #3} \def\err#1#2#3 {{\it Erratum} {\bf#1} (#2) #3} \def\ib#1#2#3 {{\it ibid.} {\bf#1} (#2) #3} \def\ijmp#1#2#3 {{\em Int. J. Mod. Phys.} {\bf#1} (#2) #3} \def\jetp#1#2#3 {{\em JETP Lett.} {\bf#1} (#2) #3} \def\mpl#1#2#3 {{\em Mod. Phys. Lett.} {\bf#1} (#2) #3} \def\nim#1#2#3 {{\em Nucl. Instr. Meth.} {\bf#1} (#2) #3} \def\nc#1#2#3 {{\em Nuovo Cim.} {\bf#1} (#2) #3} \def\np#1#2#3 {{\em Nucl. Phys.} {\bf#1} (#2) #3} \def\pl#1#2#3 {{\em Phys. Lett.} {\bf#1} (#2) #3} \def\prep#1#2#3 {{\em Phys. Rep.} {\bf#1} (#2) #3} \def\prev#1#2#3 {{\em Phys. Rev.} {\bf#1} (#2) #3} \def\pr#1#2#3 {{\em Phys. Rev.} {\bf#1} (#2) #3} \def\prl#1#2#3 {{\em Phys. Rev. Lett.} {\bf#1} (#2) #3} \def\ptp#1#2#3 {{\em Prog. Th. Phys.} {\bf#1} (#2) #3} \def\rmp#1#2#3 {{\em Rev. Mod. Phys.} {\bf#1} (#2) #3} \def\rpp#1#2#3 {{\em Rep. Prog. Phys.} {\bf#1} (#2) #3} \def\sjnp#1#2#3 {{\em Sov. J. Nucl. Phys.} {\bf#1} (#2) #3} \def\spj#1#2#3 {{\em Sov. Phys. JEPT} {\bf#1} (#2) #3} \def\zp#1#2#3 {{\em Zeit. Phys.} {\bf#1} (#2) #3} \def\epj#1#2#3 {{\em Eur. Phys. J.} {\bf#1} (#2) #3} \def\cpc#1#2#3 {{\em Comput. Phys. Commun.} {\bf#1} (#2) #3} % % % \begin{document} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \par {\bf Figure 1: \ } Diffractive $\rho$ meson production: a) proton dissociation; b) elastic process. %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \bigskip \par {\bf Figure 2: \ } Comparison between the proton dissociative data sample (dots) and the MC (histogram) for the following variables: a) positron polar angle $\theta_{e}$; b) $\rho$ meson polar angle $\theta_{\rho}$; c) $\rho$ meson momentum transverse to the beam direction $P_t(\rho)$; d) angle $\Phi$ between the $\rho$ meson production and decay planes; e) cosine of the polar angle $\vartheta$ and f) azimuthal angle $\varphi$ of the decay $\pi^+$ in the $\rho$ meson rest frame with respect to the $\rho$ meson direction in the $\gamma * p$ rest frame system; g) $Q^2$; h) $W$; i) $\tpr$. \bigskip \par {\bf Figure 3: \ } a) Invariant $\pi^+ \pi^-$ mass spectrum of the proton dissociative data sample for \mbox{$\tpr\, <\, 1.5\, \GeVsq$}; the dotted line corresponds to the nonresonant background; the dashed line includes additionally the $\rho$ meson signal; the full line represents all contributions, including additionally the $\omega$ and $\phi$ meson reflections. b) The Ross and Stodolsky parameter as a function of $Q^2$. Full circles correspond to the measurements in this analysis for the proton dissociative channel; open circles are from [H1 Coll., C.\ Adloff et al., \epj {C13} {2000} {371}] for the elastic channel. \bigskip \par {\bf Figure 4: \ } a) The $\gamma^* p$ cross section for proton dissociative (this analysis, full circles) and elastic ([H1 Coll., C.\ Adloff et al., \epj {C13} {2000} {371}], open circles) $\rho$ meson production as a function of $Q^2$ for $W=75\, \GeV$. The proton dissociative cross section is restricted to the $\tpr\,<\,1.5\,\GeVsq$ range. b) $Q^2$ dependence of the ratio of the proton dissociative to the elastic $\rho$ meson production cross sections both measured in this analysis (circles) for $W \,=\,75\,\GeV$, previous H1 measurements in electroproduction [H1 Coll., C.\ Adloff et al., \zp {C75} {1997} {607}] (square) for $7