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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi, </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I think there are possibly two problems in the component
Powder2: </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><b><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial;font-weight:bold'>Line 105</span></font></b><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'> : I think it
should be l=v*(dt-t0) instead of v*dt. The attenuation due to scattering was
therefore much larger than expected. </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> 103 dt = rand01()*(t1 - t0) + t0; /* Time
of scattering */</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> 104 PROP_DT(dt);
/* Point of scattering */</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> 105 l = v*dt;
/* Penetration in sample */</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>The other problem is on <b><span style='font-weight:bold'>line
170</span></b> : When using focus_aw and focus_ah. The angles should be
provided in radians and not degrees as suggested in the component. Otherwise,
DEG2RAD should be use to convert the focus_aw and focus_ah parameters when
calling the routine randvec_target_rect_angular. </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>170 randvec_target_rect_angular(&vx,
&vy, &vz, &solid_angle, </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>171
aim_x, aim_y, aim_z, focus_aw, focus_ah, ROT_A_CURRENT_COMP);</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoAutoSig><font size=3 color=red face="Times New Roman"><span
style='font-size:12.0pt;color:red'>______________________________________</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Dr Laurent Chapon</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Instrument Scientist</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>ISIS</span></font> department</p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Bldg R3</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Rutherford Appleton Laboratory</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Chilton, Didcot</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>OX11 0QX</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>UK</span></font></p>
<p class=MsoAutoSig><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>+44(0)1235-446090</span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> </span></font></p>
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