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Hello Stepan, The field I released was the quarter plane B_Y at y=0. The file was named b18d36.dat. Norman ________________________________________ From: Stepan Stepanyan [[log in to unmask]] Sent: Monday, March 10, 2014 7:25 PM To: McCormick, Jeremy I. Cc: Nelson, Timothy Knight; hps-software; Graf, Norman A. Subject: Re: update on HPS 3d mag field Jeremy, I think you are showing only field distribution what is in the file, which is only half plane (X, Z) for Z<=0. If you let me know which files did you use I can comment on X points. In the field maps points were generated for X=0 to X=25 cm with steps of 1 cm. In addition, Z=0 for the field map should have correspond to the center of the magnet, which is not in the picture, I think. In the attachment I am sending a zip file which has field maps for central field of 5000G. Just want to make sure we are talking about the same maps. Hope this will help. Regards, Stepan On 3/10/14, 7:14 PM, McCormick, Jeremy I. wrote: > Hi, Tim/Stepan, > > What about the field display do you think is wrong vis-a-vis the input field map? > > I’m in contact with the Geant4 developers on this, so it would be good to know so I can request a fix. Tim, I wasn’t sure what you meant on this. > > As far as the extent of the field map in -Z, I think that this is something that needs to be done in the conversion from the unfolded single plane set of points to the 3D version. Norman must have that code/script, but I haven’t seen it. This would be good to put into the SVN someplace (sandbox even) so it can be improved. > > —Jeremy > > On Mar 10, 2014, at 7:46 AM, Stepan Stepanyan <[log in to unmask]> wrote: > >> Hi TIm, >> >> Yes, I suspected that it might be a visualization issue. >> The reason I was not sure is that I can see the same as you described >> about colors and arrows but simply as 1/2 field with Z=0 not at the >> center of the magnet. >> >> Thanks, Stepan >> On 3/10/14 10:36 AM, Nelson, Timothy Knight wrote: >>> 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 ######################################################################## 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