The physical detector has certainly not been moved, and is accurate to better than 1mm. The imageplane you talk about is constructed in the code from ideal assumption on positioning and properties of the mirror. Are the numbers different from the previous years ? if yes by how much? Is this done with the final T5 geometry ? a) I doubt since it is not yet in DB awaiting a few more checks on auau zero field runs, and DC calibrations for auau. I recomend one change the offset in analysis, and not in DB, but as indicated these are likely not final. Another note on RICH is that I think the index of refraction should be in DB having values store at the level of one per 1 to 2 weeks. flemming ---------------------------------------------------------------- Flemming Videbaek Physics Department Brookhaven National Laboratory e-mail: videbaek@bnl.gov phone: 631-344-4106 ----- Original Message ----- From: "Claus O. E. Jorgensen" <ekman@nbi.dk> To: "brahms-dev" <brahms-dev-l@lists.bnl.gov> Sent: Wednesday, May 26, 2004 11:08 AM Subject: [Brahms-dev-l] RICH image plane offset > > Hi, > > I just checked the alignment of the RICH image plane - this is done using > the CheckGeometry option in the rich pid module (which gives the radial > distance from the single hits to the reconstructed ring as function of > phi). > > It looks as is the image plane is off by ~0.35 cm. This can be fixed by > moving the image plane position in the software > > richPidModule->SetImagePlaneOffset(-0.204,-0.407); > > or by changing the RICH geometry (rotation) on the bfs platform. How > well do we know the RICH position? Was it moved before this run? Should we > change the RICH geometry in the db or shift the default image plane > position in the reco scripts? > > Cheers, > > Claus > > _______________________________________________ > Brahms-dev-l mailing list > Brahms-dev-l@lists.bnl.gov > http://lists.bnl.gov/mailman/listinfo/brahms-dev-l > _______________________________________________ Brahms-dev-l mailing list Brahms-dev-l@lists.bnl.gov http://lists.bnl.gov/mailman/listinfo/brahms-dev-lReceived on Wed May 26 11:19:32 2004
This archive was generated by hypermail 2.1.8 : Wed May 26 2004 - 11:19:50 EDT