Proposition for the Beam Smearing Implementation inside Pandaroot - PowerPoint PPT Presentation

Mitglied der Helmholtz-Gemeinschaft Proposition for the Beam Smearing Implementation inside Pandaroot December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns

Outiline Introduction and Motivation FairPrimaryGenerator Vertex Smearing HESR Beam Properties Beam Smearing Tentative Implementation Conclusion December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 2 13

Introduction and Motivation December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 3 13

Introduction and Motivation Beam smearing can be done by acting on the outgoing generated particles (cf. PCM 09.09 (Smearing of the DPM outpout)). December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 3 13

Introduction and Motivation Beam smearing can be done by acting on the outgoing generated particles (cf. PCM 09.09 (Smearing of the DPM outpout)). Similarly, one can operate by using FairPrimaryGenerator (modified). December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 3 13

Introduction and Motivation Beam smearing can be done by acting on the outgoing generated particles (cf. PCM 09.09 (Smearing of the DPM outpout)). Similarly, one can operate by using FairPrimaryGenerator (modified). But, the current implementation FairPrimaryGenerator can smear only vertices = ⇒ Angular smearing should be implemented (beam particles do not have identical 4-momemtum) December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 3 13

Introduction and Motivation Beam smearing can be done by acting on the outgoing generated particles (cf. PCM 09.09 (Smearing of the DPM outpout)). Similarly, one can operate by using FairPrimaryGenerator (modified). But, the current implementation FairPrimaryGenerator can smear only vertices = ⇒ Angular smearing should be implemented (beam particles do not have identical 4-momemtum) Also, the vertex smearing should be modified according to the HESR beam properties. December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 3 13

FairPrimaryGenerator Vertex Smearing In the simulation macro: FairPrimaryGenerator* primGen = new FairPrimaryGenerator(); primGen->SetTarget(0.0, 0.2); primGen->SmearVertexZ(kTRUE); primGen->SetBeam(0.0, 0.0, 0.08, 0.08); primGen->SmearVertexXY(kTRUE); December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 4 13

FairPrimaryGenerator Vertex Smearing In the simulation macro: FairPrimaryGenerator* primGen = new FairPrimaryGenerator(); primGen->SetTarget(0.0, 0.2); a flat distribution for the Z-position of the primGen->SmearVertexZ(kTRUE); vertex with a width of 0 . 2 cm centered on 0.0 primGen->SetBeam(0.0, 0.0, 0.08, 0.08); X and Y will be smeared both by a gaussian primGen->SmearVertexXY(kTRUE); centered on 0.0, with σ = 0 . 08 cm . December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 4 13

FairPrimaryGenerator Vertex Smearing In the simulation macro: FairPrimaryGenerator* primGen = new FairPrimaryGenerator(); primGen->SetTarget(0.0, 0.2); a flat distribution for the Z-position of the primGen->SmearVertexZ(kTRUE); vertex with a width of 0 . 2 cm centered on 0.0 primGen->SetBeam(0.0, 0.0, 0.08, 0.08); X and Y will be smeared both by a gaussian primGen->SmearVertexXY(kTRUE); centered on 0.0, with σ = 0 . 08 cm . Run a simulation: fRun->SetGenerator(primGen); FairBoxGenerator* boxGen =... boxGen->SetXYZ(0., 0., 0.); primGen->AddGenerator(boxGen); December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 4 13

Smearing Output Entries 5000 Entries 5000 Entries 5000 Entries 5000 Entries 5000 Entries 5000 Mean Mean 0 0 Mean Mean 0 0 Mean Mean 0 0 5000 RMS RMS 0 0 5000 RMS RMS 0 0 5000 RMS RMS 0 0 4000 4000 4000 Before vertex smearing 3000 3000 3000 2000 2000 2000 1000 1000 1000 0 0 0 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 x [cm] y [cm] z [cm] Entries Entries 5000 5000 Entries Entries 5000 5000 Entries Entries 5000 5000 Mean −0.001164 Mean −0.001164 Mean −0.00129 Mean −0.00129 Mean 0.0007176 Mean 0.0007176 300 RMS RMS 0.07979 0.07979 RMS RMS 0.08051 0.08051 RMS RMS 0.05748 0.05748 250 250 250 200 After vertex smearing 200 200 150 150 150 100 100 100 50 50 50 0 0 0 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 x [cm] y [cm] z [cm] 1 D. Reistad, B. Galnander, K. Rathsman, A. Sidorin, "Calculations on High-Energy Electron Cooling in the HESR", Proceedings of COOL 2007, Bad Kreuznach. and V.Ziemann, NIMA 556 (2006) 641. December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 5 13

Smearing Output Entries 5000 Entries 5000 Entries 5000 Entries 5000 Entries 5000 Entries 5000 Mean Mean 0 0 Mean Mean 0 0 Mean Mean 0 0 5000 RMS RMS 0 0 5000 RMS RMS 0 0 5000 RMS RMS 0 0 4000 4000 4000 Before vertex smearing 3000 3000 3000 2000 2000 2000 1000 1000 1000 0 0 0 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 x [cm] y [cm] z [cm] Entries Entries 5000 5000 Entries Entries 5000 5000 Entries Entries 5000 5000 Mean −0.001164 Mean −0.001164 Mean −0.00129 Mean −0.00129 Mean 0.0007176 Mean 0.0007176 300 RMS RMS 0.07979 0.07979 RMS RMS 0.08051 0.08051 RMS RMS 0.05748 0.05748 250 250 250 200 After vertex smearing 200 200 150 150 150 100 100 100 50 50 50 0 0 0 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 x [cm] y [cm] z [cm] This should be treated differently according the HESR beam properties 1 1 D. Reistad, B. Galnander, K. Rathsman, A. Sidorin, "Calculations on High-Energy Electron Cooling in the HESR", Proceedings of COOL 2007, Bad Kreuznach. and V.Ziemann, NIMA 556 (2006) 641. December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 5 13

Smearing Output Entries 5000 Entries 5000 Entries 5000 Entries 5000 Entries 5000 Entries 5000 Mean Mean 0 0 Mean Mean 0 0 Mean Mean 0 0 5000 RMS RMS 0 0 5000 RMS RMS 0 0 5000 RMS RMS 0 0 4000 4000 4000 Before vertex smearing 3000 3000 3000 2000 2000 2000 1000 1000 1000 0 0 0 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 x [cm] y [cm] z [cm] Entries Entries 5000 5000 Entries Entries 5000 5000 Entries Entries 5000 5000 Mean −0.001164 Mean −0.001164 Mean −0.00129 Mean −0.00129 Mean 0.0007176 Mean 0.0007176 300 RMS RMS 0.07979 0.07979 RMS RMS 0.08051 0.08051 RMS RMS 0.05748 0.05748 250 250 250 200 After vertex smearing 200 200 150 150 150 100 100 100 50 50 50 0 0 0 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 −0.4 −0.3 −0.2 −0.1 0 0.1 0.2 0.3 0.4 x [cm] y [cm] z [cm] This should be treated differently according the HESR beam properties 1 + angluar smearing 1 D. Reistad, B. Galnander, K. Rathsman, A. Sidorin, "Calculations on High-Energy Electron Cooling in the HESR", Proceedings of COOL 2007, Bad Kreuznach. and V.Ziemann, NIMA 556 (2006) 641. December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 5 13

Antiproton Beam Properties December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 6 13

Antiproton Beam Properties , the emittance ε of the ¯ At the IP p -beam is 1 mm mrad . December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 6 13

Antiproton Beam Properties , the emittance ε of the ¯ At the IP p -beam is 1 mm mrad . ε = 2 σ x · 2 σ θ σ x : RMS of the transversal divergance of the beam. σ θ : RMS of the angular divergance of the beam. December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 6 13

Antiproton Beam Properties , the emittance ε of the ¯ At the IP p -beam is 1 mm mrad . ε = 2 σ x · 2 σ θ σ x : RMS of the transversal divergance of the beam. σ θ : RMS of the angular divergance of the beam. For σ x ≤ 0 . 8 mm , L eff ≥ 0 . 8 L max because of the beam-target overlap (pellet target). December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 6 13

Vertex Smearing Event-by-event smearing: December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 7 13

Vertex Smearing Event-by-event smearing: Choose σ x = σ y = 0 . 8 mm . December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 7 13

Vertex Smearing Event-by-event smearing: Choose σ x = σ y = 0 . 8 mm . If σ x ≤ 0 . 5 × R ⇒ Homogeneous "square" distribution of ¯ = p in the beam with a side of ( 2 × σ x ) . where R is the cross section radius of the pellet flux ( R ∼ 2 mm ). December 10, 2009 T. Randriamalala, J. Ritman and T. Stockmanns 7 13