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<P><FONT SIZE=4 FACE="Arial">Hi,</FONT>
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<P><FONT SIZE=4 FACE="Arial">Maybe someone here can give me some advices. I have trouble to understand the positron-range results generated with GATE. </FONT></P>
<P><FONT SIZE=4 FACE="Arial">For F18, the positron range distribution (see attached gif figure) shows an unexpected peak between 1 and 2 mm, which is not present in published literature (Levin and Hoffman, Craig S Levin and Edward J Hoffman 1999 Phys. Med. Biol. *44* 781-799; Laforest R, Rowland DJ, Welch MJ. 2002. MicroPET imaging with nonconventional isotopes. IEEE Trans Nucl Sci 49, 2119-2126). The figure can be easily reproduced by running benchmarkPET scripts, just remove the Oxygen15 parts in the sources.mac. We saw similar results with Oxygen15. </FONT></P>
<P><FONT SIZE=4 FACE="Arial">The GATE version we are using is v1.0. I don’t see this issue mentioned in the later version’s releaseNotes. </FONT>
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<P><FONT SIZE=4 FACE="Arial">Thanks in advance!</FONT>
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<P><FONT SIZE=2 FACE="Arial">Rutao Yao, Ph.D.</FONT>
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<P><FONT SIZE=2 FACE="Arial">University at Buffalo</FONT>
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