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Hello Sho, The perspective pictures look nice. About the geometry: I think the beam comes in at 30.5 mrad, but it does not come in on the center axis of the magnet. We had the entire magnet shifted by 88.485*mm from the "straight through" beam line (if all magnets are off in the chicane). With the magnets at 0.5 T we then have the beam at the target position at -21.12 mm. Electron beam positions at various locations in the system calculated using the mapped magnetic field are: Name Z Pos X Pos Local Z pos Local X pos A1 - 110 -314.2 mm 55.71 mm -32.78 mm A2 - 111 -100 mm 64.14 mm -24.34 mm B1 - 10 Target (+2 mm) 2 mm 67.37 mm -21.12 mm A3 - 112 Silicon 1 +100 mm 69.64 mm -400 mm -18.84 mm A4 - 113 Silicon 2 +200 mm 71.48 mm -300 mm -17.1 mm A5 - 114 Silicon 3 +300 mm 72.63 mm -200 mm -15.86 mm A6 - 115 Silicon 4 +500 mm 73.22 mm 0 mm -15.26 mm A7 - 116 Silicon 5 +700 mm 71.10 mm +200 mm -17.38 mm A8 - 117 Magnet Exit +900.1 mm 66.29 mm +400 mm -22.20 mm B3 - 12 Ecal Entry 1319 mm 50.64 mm -37.84 mm B4 - 13 Ecal Middle 1549 mm 41.54 mm -135 mm -45.27 mm For the photons this is: Name Z Pos X Pos Local Z pos Local X pos A1 - 110 -314.2 mm - A2 - 111 -100 mm - B1 - 10 Target 0 mm - A3 - 112 Silicon 1 +100 mm 70.36 mm -400 mm -18.12 mm A4 - 113 Silicon 2 +200 mm 73.42 mm -300 mm -15.07 mm A5 - 114 Silicon 3 +300 mm 76.47 mm -200 mm -12.02 mm A6 - 115 Silicon 4 +500 mm 82.58 mm 0 mm -5.91 mm A7 - 116 Silicon 5 +700 mm 88.68 mm +200 mm 0.194 mm A8 - 117 Magnet exit +900.1 mm 94.79 mm +400 mm 6.303 mm B3 - 12 Ecal Entry 1319 mm 107.6 mm 19.10 mm B4 - 13 Ecal Middle 1549 mm 114.6 mm -135 mm 26.11 mm The ECal should be centered on the photon beam at the front face, so not centered on the center of the magnet but shifted towards the positron. The Ecal Entry point at z=1319mm is not at the crystal face but at the front of the flange. At the front of the crystals the shift should be 21.38mm to the positron side (so that is the x location in between crystals 23 and 24 (counting from one end) compared to the centerline of the magnet) . I had the front face of the crystals at Z=1397mm. This may be too far back. The 2cm thick front flange has the target facing edge at 1318mm, which is the exit flange of the vacuum system. So I have 59mm between the rear face of the flange and the front face of the crystals. I had the center of the analyzing magnet at z=45.72 cm compared to the target at z=0; The photon hole in the Ecal vacuum system has to be at 30.5 mrad. Below is a screenshot that shows the photons go exactly through the center of the photon hole. The beam in this case is calculated to go through the entire chicane of 3 magnets. Best, Maurik On Nov 13, 2012, at 9:35 PM, Sho Uemura wrote: > <flange_3d_noedges.png> ######################################################################## Use REPLY-ALL to reply to list To unsubscribe from the HPS-SOFTWARE list, click the following link: https://listserv.slac.stanford.edu/cgi-bin/wa?SUBED1=HPS-SOFTWARE&A=1