<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class="">You mentioned that t<span style="orphans: 2; white-space: pre-wrap; widows: 2;" class="">he crystal ring diameter is 16.1 cm, transaxial and axial FOV are 10.0 cm and 12.7 cm, so the following macro should work.</span><div class=""><div style="orphans: 2; widows: 2;" class=""><span style="white-space: pre-wrap;" class=""><br class=""></span></div><div style="orphans: 2; widows: 2;" class=""><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class=""># W O R L D</pre><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">/gate/world/geometry/setXLength 20. cm
/gate/world/geometry/setYLength 20. cm
/gate/world/geometry/setZLength 20. cm</pre><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">
# S Y S T E M (E C A T)
/gate/world/daughters/name ecat
/gate/world/daughters/insert cylinder
/gate/ecat/setMaterial Air
/gate/ecat/geometry/setRmax 90.5 mm <span class="Apple-tab-span" style="white-space:pre"> </span># Outer diameter
/gate/ecat/geometry/setRmin 80.5 mm <span class="Apple-tab-span" style="white-space:pre"> </span># ring diameter 16.1 cm => Radius 80.5 mm
/gate/ecat/geometry/setHeight 127 mm # 12.7 cm axial FOV
/gate/ecat/vis/forceWireframe</pre><div class=""><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class=""># B L O C K
/gate/ecat/daughters/name vol1
/gate/ecat/daughters/insert box
/gate/vol1/placement/setTranslation <span style="font-family: Menlo; font-size: 11px; background-color: rgb(252, 252, 252);" class="">85 0 0 mm </span><br class="">/gate/vol1/geometry/setXLength 10.0 mm
/gate/vol1/geometry/setYLength 31.7 mm
/gate/vol1/geometry/setZLength 31.7 mm # 127/4 ( 4-ring) = 31.75 mm
/gate/vol1/setMaterial Air
/gate/vol1/vis/setColor yellow
/gate/vol1/vis/forceWireframe</pre><div class=""><span style="white-space: pre-wrap;" class=""># C R Y S T A L</span></div></div><div class=""><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">/gate/vol1/daughters/name vol2
/gate/vol1/daughters/insert box
/gate/vol2/geometry/setXLength 10.0 mm
/gate/vol2/geometry/setYLength 1.51 mm
/gate/vol2/geometry/setZLength 1.51 mm
/gate/vol2/setMaterial LSO <span class="Apple-tab-span" style="white-space:pre"> </span> # LSO crystals
/gate/vol2/vis/setColor red
<br class=""></pre><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class=""><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class=""># R E P E A T C R Y S T A L
/gate/vol2/repeaters/insert cubicArray
/gate/vol2/cubicArray/setRepeatNumberX 1
/gate/vol2/cubicArray/setRepeatNumberY 20
/gate/vol2/cubicArray/setRepeatNumberZ 20
/gate/vol2/cubicArray/setRepeatVector 0. 1.59 1.59 mm</pre><div class=""># R E P E A T BLOCK</div><div class=""><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">/gate/vol1/repeaters/insert linear
/gate/vol1/linear/setRepeatNumber 4
/gate/vol1/linear/setRepeatVector 0. 0. 31.7 mm</pre><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">
/gate/vol1/repeaters/insert ring
/gate/vol1/ring/setRepeatNumber 16</pre><div class=""><br class=""></div><div class=""># A T T A C H S Y S T E M</div><div class="">/gate/systems/ecat/block/attach vol1</div><div class="">/gate/systems/ecat/crystal/attach vol2</div></div><div class=""><br class=""></div><div class=""># A T T A C H C R Y S T A L SD</div><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">/gate/vol2/attachCrystalSD
</pre></pre><div class=""><div class=""><br class=""></div></div></div><div class=""># Define phantom:</div><div class=""><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">/gate/world/daughters/name phantom
/gate/world/daughters/insert cylinder
/gate/phantom/setMaterial Water
/gate/phantom/vis/forceWireframe
/gate/phantom/vis/setColor green
/gate/phantom/geometry/setRmax 10.0 cm
/gate/phantom/geometry/setHeight 20. cm
<br class=""></pre><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">/gate/phantom/attachPhantomSD</pre><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class=""><br class=""></pre><pre style="white-space: pre-wrap; font-variant-ligatures: normal;" class="">Ashok</pre><div class=""><br class=""></div></div></div><pre style="white-space: pre-wrap; font-variant-ligatures: normal; orphans: 2; widows: 2;" class=""> </pre><div class=""><br class=""></div></div></body></html>