1 / 10

Beam pipe influence on the STS performance

Beam pipe influence on the STS performance. 14th CBM Collaboration Meeting, October 6.-9. 2009, Split, Croatia. A.Chernogorov, S.Belogurov, ITEP, Moscow. This part I will speak about. Outline: Introduction Simulation conditions Layout of the stations Pipe configurations

vance-giles
Télécharger la présentation

Beam pipe influence on the STS performance

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Beam pipe influence on the STS performance 14th CBM Collaboration Meeting, October 6.-9. 2009, Split, Croatia A.Chernogorov, S.Belogurov, ITEP, Moscow

  2. This part I will speak about Outline: • Introduction • Simulation conditions • Layout of the stations • Pipe configurations • Detailed results for one configuration • Comparative analysis for all configurations • Conclusions Leading effect: additional hits produced by delta electrons 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  3. Simulation conditions • 100 Central UrQMD Events (Au+Au@25AGeV/c) (UrQMD1.3 input file14: http://www-linux.gsi.de/~cbmsim/cbm_vmc_doc/input.htm) • Specially prepared geometry of STS stations (2.5° hole). Previous standard geometry had rectangular holes with constant height and was not suitable for our study. • Several geometries for Al and Be beam pipe • Track simulation with Geant3 (generation threshold 30 keV, Energy loss threshold 70 keV) /u/sbelogur/cbm/run/sts_sim_my.C based on standard sts_sim.C (July09 Cbmroot version) • Track reconstruction using L1Performance class /u/sbelogur/cbm/run/sts_reco_my.C based on recUrQMD_only.C by I.Vassiliev • Selection condition of tracks passing near the pipe: not less than one point of a track should belong to the cone with 5° vertex angle (MCTracks&RECOTracks) • Two level observables – excess hits due to pipe, quality of tracks reconstruction Selection condition of tracks near the pipe for analysis in order to separate effects of tracking algorithm 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  4. Layout of stations Special geometry was created for us by Anna with square holes of 2.5° aperture. Set of sensors 2, 4, 6, 12, 18 cm. For central ones sizes were introduced manually to follow the 2.5° requirement. 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  5. Layout of stations We have found that with previous geometry hit probability per strip >10% i.e. too many fakes. We introduced a new geometry with sensors of 1.4, 2, 4, 6, 12 cm and all central sensors 2 times shorter than before. 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  6. Pipe configurations For mechanical stability should be: h~D/E, where h is the thickness of the pipe;D is diameter of the pipe;E is the Young's modulus;E(Be)=300GPa, E(Al)=70GPa 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  7. Detailed results for Be tube Ø28mm h0.5mm configuration Hit density for 1, 4, 8 STS stations 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  8. Detailed results for Be tube Ø28mm h0.5mm configuration 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  9. Comparative analysis for all configurations 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

  10. Conclusion • Effects of pipe are visible for all configurations, especially for reconstruction of secondary tracks and for ghosts • Lowest effects are observed for cylindrical tube Ø20mm, largest ones for pipe having 2.5° cone’s shape • Usage of the Be allows to reduce considerably pipe’s effects in comparison with Al 14th CBM Collaboration Meeting , Split, Croatia October 6-9 2009

More Related