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Hi Stepan, I think the problems at this point are all due to the visual representation. Colors and arrow lengths are field strength, red being large and green to blue being relatively smaller. I am not sure why the field is cut off on the downstream side, but still well past z=0, in this image but I'm pretty sure that's a problem with the visualization based on the map data I saw that goes into this. Tim Sent from my iPad > On Mar 7, 2014, at 8:48 AM, "Stepan Stepanyan" <[log in to unmask]> wrote: > > Hello Jeremy, > > Thanks for implementing the field. I am not sure how much I should trust > the visual picture, but the field you have is generated from the middle of > the magnet (in Z), so if I am reading the picture correctly, field is > shifted > relative to the magnet. For completeness the same (X,+Z) distribution must > be repeated for (X,-Z) half plane. > One of things we have discussed with Norman some time ago is the need > for a full 3-D field map (B_x, B_y, B_z) for (X, Y, Z) points. Will be > good to > know this early on. > > Regards, Stepan > >> On 3/6/14 7:28 PM, McCormick, Jeremy I. wrote: >> Hi, >> >> I made a few fixes to SLIC/LCDD for the support of 3D magnetic field maps. The map’s offsets were not being set correctly, and I believe this is now fixed in the HEAD configuration of SLIC in ilcinstall. >> >> I also added the missing field data to the SVN at hps/java/trunk/fieldmap which is referenced by the detector that includes the field map. >> >> I was able to get simple visualization working with the 10.00.p01 release of Geant, and the best picture I have so far is this: >> >> http://www.slac.stanford.edu/~jeremym/hps/field/hps_field7.png >> >> This visualization tool is at an “alpha” stage of development in that project, unfortunately, but it at least gives some idea that the field has been loaded in successfully. >> >> That’s the good news. >> >> The bad news is that the performance is approximately 150x worse when using the 3D field in a Proposal2014 geometry compared to a setup with the simplistic fixed dipole. This compares the HPS-Proposal2014-v5-2pt2 detector with HPS-Proposal2014-v4-fieldmap using the event file egs_tri_2.2gev_0.00125x0_200na_5e5b_30mr_001.stdhep. >> >> So it appears to me this is not really going to be useable in large scale simulation production until the algorithm for retrieving and interpolating the field values has been significantly optimized. >> >> —Jeremy >> ######################################################################## >> 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