\documentclass{article}

\usepackage[usenames,dvipsnames]{pstricks}
\usepackage{epsfig}
\usepackage{pst-grad} % For gradients
\usepackage{pst-plot} % For axes

\usepackage{geometry}
  \geometry{paperwidth=10cm}
  \geometry{paperheight=3.5cm}

\begin{document}
\pagestyle{empty}
\psset{unit=2cm}
\begin{pspicture}(0,0)(0.1,0.1)
  \rput(-1.2,-0.8){
    \psline(0.3409375,-0.13921875)(2.5409374,-0.13921875)
    \psline[linestyle=dashed,dash=0.16cm 0.16cm](2.5409374,-0.13921875)(5.1409373,-0.13921875)
    \psline(2.5409374,-0.13921875)(4.9409375,0.86078125)
    \psline[linewidth=2pt,linecolor=White!50!Black,arrowlength=1.6,arrowinset=0.0]{->}(0.5409375,0.02078125)(1.1409374,0.02078125)
    \psline[linewidth=2pt,linecolor=White!50!Black,arrowlength=1.6,arrowinset=0.0]{->}(3.6609375,0.5207813)(4.2409377,0.7607812)
    
    \psarc(2.5409374,-0.13921875){1.0}{0.0}{22.380135}
     
    \pscircle[linecolor=Black,fillcolor=White!80!Black,fillstyle=solid](2.5409374,-0.13921875){0.085}
    
    \rput(3.8023438,0.8){$k_{\rm f}$}
    \rput(0.84234375,0.22){$k_{\rm i}$}
    \rput(2.5270312,-0.38921875){sample}
    \rput(3.65,0.07){$2\theta$}
  }
\end{pspicture} 
\end{document}