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<p>Dear Gate users</p>
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<p>I'm validating my simulations using a unit density sphere source of F-18 surrounded by water and comparing the simulation results to
<i>Stabin & Siegel (2003) </i>and <i>Stabin & Konijnenberg (2000)</i><i></i>. My simulation consists of
<span>a F-18 ion source</span> and a voxelized phantom containing the sphere. To my, limited, knowledge everything seems to be working as intended, except I'm getting a self-absorption dose, to the sphere, that is consistently (independent of the size of the
sphere) ~10% higher than the values in the reference articles. Could this be caused by the difference in physics (treatment of secondary particles etc.) between Gate/Geant4 and <span>EGS4/MCNP4B</span> (used in the reference articles)?<br>
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I would be very thankful for any help/advice!<br>
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Have a nice weekend!<br>
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<p><u>Ref:</u></p>
<p><i><span>Stabin MG. and Siegel JA. <span>Physical models and dose factors for use in internal dose assessment</span></span>.
</i><span><i>Health Phys. 85(3):294 –310; 2003.</i></span><br>
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<p><i><span>Stabin MG, Konijnenberg M. Re-evaluation of absorbed fractions for photons and electrons in small spheres. J Nucl Med 41:149–160; 2000.</span></i><br>
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<div><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">Regards</span><br>
<span style="font-size:10pt"></span><span style="font-size:11pt"></span><span style="font-size:10pt"></span><span style="font-family:"Segoe UI",sans-serif; font-size:12pt"></span><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">Gustav</span><br>
<span style="font-size:10pt"></span><br>
<img class="EmojiInsert" alt="1489736892538_KAROLINSKA_LOGO_sRGB2.jpg" src="cid:4c7db1b9-f588-4d8a-ad04-8aa621894273"><br>
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<b><i><span style="font-family:"Times New Roman",Times,serif; font-size:14pt"></span></i></b><i><span style="font-family:"Times New Roman",Times,serif; font-size:14pt">Gustav Murquist</span></i><b><i><span style="font-family:"Times New Roman",Times,serif; font-size:14pt"></span></i></b><br>
<span style="font-family:"Segoe UI",sans-serif; font-size:10pt">Medical physicist</span><br>
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<span style="font-family:"Segoe UI",sans-serif"></span><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">Nuklearmedicin Inflammation, Huddinge (C2:74)</span><br>
<span style="font-family:"Segoe UI",sans-serif"></span><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">Medicinsk Strålningsfysik och Nuklearmedicin</span><br>
<span style="font-family:"Segoe UI",sans-serif"></span><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">Karolinska Universitetssjukhuset</span><br>
<span style="font-family:"Segoe UI",sans-serif"></span><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">141 86 Stockholm</span><br>
<span style="font-family:"Segoe UI",sans-serif"></span><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">Telefon 08-585 862 92, mobil 070-001 73 03</span><br>
<span style="font-family:"Segoe UI",sans-serif"></span><span style="font-family:"Segoe UI",sans-serif; font-size:10pt">e-post gustav.murquist@karolinska.se</span><br>
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