I need to put arrows rightly into the trajectory plot and mathematica puts only 2 arrows on randomly chosen region. I give command to put 15 arraows but I see only 2 on graphic. How to manage rightly the number of arrows and place where they should be put?

k = 0.0123;
m = k/(k + 1);
\[Xi] = 0.5*(1 - 2 m);
A = 2/\[Xi];
t0 = 0;
h0 = 0.1;

\[EmptyUpTriangle]0 = Sqrt[h0^2  +  1/4];

\[CapitalOmega]0 = ((\[EmptyUpTriangle]0^2)/2)  +  
   1/\[EmptyUpTriangle]0;
s0 = Sqrt[2*\[CapitalOmega]0 - C0];
C0 = 4.1;

c1 = -\[Xi]*Sqrt[2*\[CapitalOmega]0 - C0] + h0^2;


h[t_] = Sqrt[-c1]*
   Tan[  ArcTan[h0/Sqrt[-c1]]   -   (Sqrt[-c1]/\[Xi])*(t - t0)  ];   
x[t_] = \[Xi]*Cos[t] - h[t]*Sin[t];
    y[t_] = \[Xi]*Sin[t] + h[t]*Cos[t];   
     ParametricPlot[{x[t], y[t]}, {t, 0, 12}, 
          PlotStyle -> {Black, Thickness[0.009]}, 
          AxesLabel -> {Style[OverTilde[x], Bold, 19], 
            Style[OverTilde[y], Bold, 19]}] /. 
         Line[content___] :> {Arrowheads[ConstantArray[0.08, 15], 
           Arrow[content]}

Attachments:

рис10б.png