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Hi Sho, The beam enters at 30.52 mrad, if we believe the trajectories of the mapped fields as particles propagate through them in G4. When I made up the ecal geometry, the distance I was given was 51.93 inches from the target to the exit of the pair spectrometer vacuum chamber, so 1319mm. I just verified this and that is where I still have it in my simulation. That does not mean this is still the correct number though. I wouldn't worry about a mm though. I think it is more important that we verify the correct location of the front of the crystals. I am actually not 100% sure where they should be. We'll bring it up in the meeting tomorrow, and maybe Stepan or Takashi can chime in. Best, Maurik On Nov 14, 2012, at 8:34 PM, Sho Uemura <[log in to unmask]> wrote: > Okay, great, that clears up almost everything. A few last questions: > > * Beam enters at 30, 30.5, or 31 mrad? From Maurik's table it looks like 30.5, but I've heard all three of these numbers, so . . . > > * What is the distance between the target/lip of the magnet and the front face of the flange? Maurik's e-mail gives both 1319 and 1318 mm. > > * Where exactly is the electron flange in X? > > If there's an engineering drawing of the flange that would be nice, just so I can check it against the GDML of the flange. > > It looks like there was some discussion at the 10/18 software meeting > about things that needed to be done to the geometry, and among these were > ECal and ECal flange updates. Is there anything specific that was meant by that? Who was going to do that? Was anything actually done? > > On Wed, 14 Nov 2012, Stepan Stepanyan wrote: > >> Hello Sho, >> >> There were several email exchanges on the subject while I was trying to finish mine, so sorry for >> repeats. I attached a file with geometry of ECal, vacuum chamber and the analyzing magnet, slides 2 and 3. >> >> As for your numbers, (a) I remember 31 mrad, (b) if target is at the lip of the analyzing magnet and >> we take it as Z=0, than center of the analyzing magnet should be 18 inches away, 45.72 cm, (c) ECal >> is not symmetric around the magnet and Z-axis, (d) see ECal flange and hole locations in the attached >> file. >> >> I am also attaching another file showing positions at May run, that file has distance of crystals from the flange. >> >> I am sure you have seen these before, but just in case, it will help to finalize the geometry. >> >> Regards, Stepan >> >> On 11/13/12 9:35 PM, Sho Uemura wrote: >>> Those are sections, not perspectives. They should be literally what you would see if you cut through the detector at the specified z. >>> The flange appears to be positioned so the photon hole is somewhat to one side and angled out - if you look closely at the sections you can see that the photon hole is further from the center at z=150 than it is at z=137. >>> I've attached two perspective views of the whole geometry. >>> Relevant people, please comment on whether these statements are correct, with (0, 0, 0) being the beam spot on target and the Z-axis being parallel to the magnet bore: >>> * This is the frame we want to use for SLIC/LCSim. >>> * Beam enters at an angle of 30 mrad from Z, pointing into the positron side. >>> * Center of the analyzing magnet is at z = 45.22 cm. >>> * SVT is rotated 30 mrad into the positron side. >>> * ECal is completely symmetric around the Z-axis (aside from the missing crystals). Front face is at z = 137 cm. >>> * ECal flange has photon hole shifted 16 mm to the positron side at the front face of the flange (z = 135 cm), and 30 mm to the positron side at the rear face (z = 179 cm). >>> * ECal flange has electron bulge at the size and shape seen on my sections. >>> That's what I see in this geometry. If any of these statements are false, we need to fix the geometry to match. >>> On Tue, 13 Nov 2012, Maurik Holtrop wrote: >>>> Hello Sho, >>>> I am a little confused about the pictures that you are drawing. The top one seems to have a vacuum "bulge" area that is too small. The "bulge" is supposed to fill up the gap of all the crystals that were removed. Is that some effect of the perspective? >>>> The other issue is that the photon hole should be right through the center of the ECAL. >>>> Best, >>>> Maurik >>>> Looking along the beam line, +x towards the left, +y towards the top. >>>> On Nov 13, 2012, at 7:11 PM, Sho Uemura <[log in to unmask]> wrote: >>>>> Okay, here's some sections of the flange at different values of Z; center of viewer is (0,0) I think - I have no idea what I'm doing but I managed to get SLIC to display the geometry. >>>>> Looking at the Z=150 view, it looks like the photon hole is ~15 mm (somewhat more than one crystal width) from the center, where you'd want it to be at (150 cm)*(30 mrad) = 45 mm? >>>> ######################################################################## >>>> 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 >>> ######################################################################## >>> 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 >> >> > > ######################################################################## > 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 ######################################################################## 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