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Hello Sho and Maurik, According to drawings that I have angle is 30.5 milirad, the distance from the target (magnet upstream lip) to the front face of the crystals is 137.4 cm with 4 mm error (actual measurements and drawings for magnet vacuum chamber position relative to magnet are differ by 4mm). I am not sure what is the electron flange. Regards, Stepan On 11/14/12 11:30 PM, Sho Uemura wrote: > Front of crystals 75 mm back from front of flange according to > Stepan's diagrams. > > On Wed, 14 Nov 2012, Maurik Holtrop wrote: > >> 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 >> > > ######################################################################## > 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