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