GPU-based Online Tracking Algorithms & Application to D±→K∓π±π±

A seminar talk at RUB University

Transcript

1. Mitglied der Helmholtz-Gemeinschaft 1 RUB Seminar Talk 3 February 2014, Andreas Herten GPU-based Online Tracking Algorithms & Application to D±→K∓π±π±
2. Mitglied der Helmholtz-Gemeinschaft Outline • Online Tracking for PANDA • GPUs • Online Tracking Algorithms – Triplet Finder – Hough Transforms • D±→K∓π±π± – EvtGen – Hitcounting – Tracking Benchmark – Event Reconstruction 2
3. Mitglied der Helmholtz-Gemeinschaft PANDA & ONLINE TRACKING 3
4. Mitglied der Helmholtz-Gemeinschaft PANDA — The Experiment 4 13 m p p
5. Mitglied der Helmholtz-Gemeinschaft PANDA — The Experiment 4 13 m p p Magnet STT MVD GEMs FTS
6. Mitglied der Helmholtz-Gemeinschaft PANDA — Event Reconstruction • Continuous read out – Novel feature – Background & signal similar – No hardware trigger based on few sub-detectors, but online event reconstruction using full detector information 5 (Reject background events, save interesting events) Reduction Amount: Time: ~1/1000 50 ns/evt Storage space for offline analysis 3 PB/y Event: Raw data: 2 × 107/s 200 GB/s Rate Full version
7. Mitglied der Helmholtz-Gemeinschaft PANDA — Read Out Scheme 6
8. Mitglied der Helmholtz-Gemeinschaft PANDA — Read Out Scheme 6
9. Mitglied der Helmholtz-Gemeinschaft PANDA — Read Out Scheme Requirements to Online Tracking • Fast • Sophisticated algorithms possible; reprogrammable • Parallelism beyond single devices • Speed ↔ precision 6
10. Mitglied der Helmholtz-Gemeinschaft PANDA — Read Out Scheme Requirements to Online Tracking • Fast • Sophisticated algorithms possible; reprogrammable • Parallelism beyond single devices • Speed ↔ precision 6 GPUs
11. Mitglied der Helmholtz-Gemeinschaft GPUS 7
12. 8 Mitglied der Helmholtz-Gemeinschaft CPU & GPU • Originally used for computer games • Programming available as General Purpose GPU, GPGPU StarCraft II
13. 8 Mitglied der Helmholtz-Gemeinschaft CPU & GPU CPU GPU • Originally used for computer games • Programming available as General Purpose GPU, GPGPU StarCraft II
14. 8 Mitglied der Helmholtz-Gemeinschaft CPU & GPU CPU GPU • Originally used for computer games • Programming available as General Purpose GPU, GPGPU StarCraft II
15. Mitglied der Helmholtz-Gemeinschaft CPU & GPU 9 GPU CPU
16. Mitglied der Helmholtz-Gemeinschaft CPU & GPU 9 GPU CPU a1 → b1 → c1 a2 → b2 → c2 a3 → … parallel a1 → b1 → c1; a2 → b2 → c2; a3 → … serial
17. Mitglied der Helmholtz-Gemeinschaft Challenges of GPU programming 10 = Leveraging GPU processing power Writing adequate algorithms adequately parallel • non-blocking • computing-intensive Getting data to GPU integration into DAQ • high-level data +
18. Mitglied der Helmholtz-Gemeinschaft Challenges of GPU programming 10 = Leveraging GPU processing power Writing adequate algorithms adequately parallel • non-blocking • computing-intensive Getting data to GPU integration into DAQ • high-level data +
19. Mitglied der Helmholtz-Gemeinschaft 11 ALGORITHMS #1 Triplet Finder Hough Transform
20. Mitglied der Helmholtz-Gemeinschaft 12 Triplet Finder • Algorithm specifically designed for the PANDA Straw Tube Tracker (STT) http://www.fz-juelich.de/ias/jsc/ 1.5 m • Ported to GPU – CUDA, Dynamic Parallelism, Thrust – Quality of tracks comparable to CPU Drift tubes: t0 needed for drift circles → r(tArrive-t0) 1cm Resolution without t0: (0.1 cm) Resolution with t0: (0.015 cm)
21. Mitglied der Helmholtz-Gemeinschaft 13 Triplet Finder • Idea: Use only subset of detector as seed – Don‘t use STT isochrones (drift times) • Features – Fast & robust algorithm, no t0 needed – Many tuning possibilities More
22. Mitglied der Helmholtz-Gemeinschaft 14 Triplet Finder — Times K20X
23. Mitglied der Helmholtz-Gemeinschaft 14 Triplet Finder — Times K20X
24. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Bunching Wrapper – Hits from one event have similar timestamps – Combine hits to sets (bunches) which occupy GPU best 15
25. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Bunching Wrapper – Hits from one event have similar timestamps – Combine hits to sets (bunches) which occupy GPU best 15 Hit
26. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Bunching Wrapper – Hits from one event have similar timestamps – Combine hits to sets (bunches) which occupy GPU best 15 Hit Event
27. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Bunching Wrapper – Hits from one event have similar timestamps – Combine hits to sets (bunches) which occupy GPU best 15 Hit Event
28. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Bunching Wrapper – Hits from one event have similar timestamps – Combine hits to sets (bunches) which occupy GPU best 15 Hit Event Bunch
29. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Bunching Wrapper – Hits from one event have similar timestamps – Combine hits to sets (bunches) which occupy GPU best 15 Hit Event Bunch (N2) → (N)
30. Mitglied der Helmholtz-Gemeinschaft 16 Triplet Finder — Bunching K20X Performance
31. Mitglied der Helmholtz-Gemeinschaft 17 Triplet Finder — Kepler vs. Maxwell Performance for different GPUs K20X Maxwell Performance: 1.3 TFLOPSsingle Price: 130 € 750 Ti Kepler Performance: 3.95 TFLOPSsingle Price: 3600 €
32. Mitglied der Helmholtz-Gemeinschaft ALGORITHMS #2 18 Triplet Finder Hough Transform
33. Mitglied der Helmholtz-Gemeinschaft Algorithm: Hough Transform • Basic Hough idea: Generate lots of independent track parameters; extract best-matching one. • Three Hough Transforms: – Line Hough Transform • Around point-like hits (MVD, STT-prefit) • Around isochronuous hits (STT) – Circle Hough Transform (MVD, STT, GEM, …) 19 x y x y Mitglied der Helmholtz-Gemeinschaft Hough Transform — Princip → Bin giv r α
34. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 20 • Circle Hough with isochrones (xC, yC)ij = (xi + sij cos φj, yi + sij sin φj) 2 sij = ρi 2 - xi 2 - yi 2 / (xi cos φj + yi sin φj + ρi)
35. -300 -200 -100 0 100 200 300 -300 -200 -100 0 100 200 300 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 0 2 4 6 8 10 12 14 16 18 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 21
36. -300 -200 -100 0 100 200 300 -300 -200 -100 0 100 200 300 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 0 2 4 6 8 10 12 14 16 18 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 21 π+ π- π- K- K+ π+
37. -300 -200 -100 0 100 200 300 -300 -200 -100 0 100 200 300 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 0 2 4 6 8 10 12 14 16 18 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 22
38. -300 -200 -100 0 100 200 300 -300 -200 -100 0 100 200 300 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 0 2 4 6 8 10 12 14 16 18 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 22
39. -300 -200 -100 0 100 200 300 -300 -200 -100 0 100 200 300 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 0 2 4 6 8 10 12 14 16 18 HoughHisto_1 Entries 171941 Mean x -3.39 Mean y 14.01 RMS x 101.6 RMS y 123.5 Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 22
40. Mitglied der Helmholtz-Gemeinschaft Circle Hough — GPU Performance 23 i5 @ 3.3 GHz Variation of number of threads (and blocks): GPU vs. CPU GTX 580
41. Mitglied der Helmholtz-Gemeinschaft Circle Hough — GPU Performance 23 i5 @ 3.3 GHz Variation of number of threads (and blocks): GPU vs. CPU GTX 580 ~20 ×
42. Mitglied der Helmholtz-Gemeinschaft Circle Hough — Challenges & Todo • CPU: – Benchmarking; cut parameters – Code cleanup • GPU: – Performance w/o PandaRoot – More parallelism (hit → set of hits) – Data transfer • Tracking: Data or computing intensive? • Different types of memories • Asynchronous transfer & processing 24
43. Mitglied der Helmholtz-Gemeinschaft GPUs — Summary • Triplet Finder: Performance-optimized – 14 µs / event • Circle Hough: PandaRoot-integrated • GPUs: Feasible for part of PANDA‘s online event reconstruction system – Also important: Data transfer to GPU 25 PndCircleHoughTask  *  chTracker  =  new  PndCircleHoughTask(); chTracker-­‐>AddHitBranch("MVDHitsStrip"); chTracker-­‐>AddHitBranch("STTHit"); chTracker-­‐>SetUseGpu(true);
44. Mitglied der Helmholtz-Gemeinschaft D± → K∓ π± π± 26 Description & EvtGen Detector Response Tracking Performance Event Reconstruction
45. Mitglied der Helmholtz-Gemeinschaft D± → K∓ π± π± 27 Description & EvtGen Detector Response Tracking Performance Event Reconstruction
46. 4 Proceedings of the DPF-2009 Conference, Detroi Mass (MeV) 3000 3500 4000 4500 Charmonium Spectrum          ? K c J/\ K' c \' \(4040) \(4415) \(4160) h c F c0 F c1 F c2 F' c2 \'' 13S 1 23S 1 13D 1 11S 0 21S 0 31S 0 41S 0 11P 1 21P 1 13P 1 23P 1 23P 0 13P 0 13P 2 23P 2 13F 2 11D 2 13D 2 13D 3 23D 3 23D 2 21D 2 33S 1 23D 1 43S 1 33D 1 DD DD* 53S 1 Y(4260) Z(3940) Y(4660) Y(4350) Y(4008) Z+(4430) Z 1 (4050) X(3872) X(3940) Y(3940) Z 2 (4250) X(4160) Y(4140) D s D s D*D* D s D* s D* s D* s DD 1 D s D s1 , D* s D s0 D*D 2 D* s D s2 Y(4630) Figure 5: The Charmonium spectrum. The solid lines are quark mode predictions [21] the shaded lines are the observed conventional charmonium states [22], the hori- zontal dashed lines represent various D(∗) s ¯ D(∗) s thresholds, and the (red) dots are the newly discovered charmonium- like states placed in the column with the most probable spin assignment. The states in the last column do not fit elsewhere and appear to be truly exotic. Figure 6 in B → mass di the B+ backgro total un 4143.0 3.7 Me JP C = argue t in B → re 1. (Left) Invariant mass of the 3⇡ system for 0.1 GeV/c2 < t0 < 1.0 GeV2/c2 (histogram), and intensity of the background wave a flat distribution in three-body phase space (red triangles), obtained from a partial wave analysis in 40 MeV/c2 bins of the 3⇡ mas escaled to the binning of the histogram (from [1]). (Right) Intensities of major waves (a) 1++0+⇢⇡ S, (b) 2 +0+ f2⇡ S, (c) 2++1+⇢⇡, as the intensity of the exotic wave (d) 1 +⇢⇡ P, as determined in the fit in mass bins (data points with error bars). The lines represen sult of the mass-dependent fit (from [1]). . Ds Ds * D Ds(2317) (2317) Ds(2460) (2460) Ds(2710) (2710) Ds (2860) (2860) J Ds(3040) (3040) Observed Ds1 Ds2 Mass (MeV/c ) 3000 3500 4000 4500 ? c J/ ' c ' (4040) (4415) (4160) h c c0 c1 c2 ' c2 '' 13S 1 23S 1 13D 1 11S 0 21S 0 31S 0 41S 0 11P 1 21P 1 13P 1 23P 1 23P 0 13P 0 13P 2 23P 2 13F 2 11D 2 13D 2 13D 3 23D 3 23D 2 21D 2 33S 1 23D 1 43S 1 33D 1 53S 1 Y(4260) Z(3940) Y(4660) Y(4350) Y(4008) Z+(4430) Z 1 (4050) X(3872) X(3940) Y(3940) Z 2 (4250) X(4160) Y(4140) D D D D Y(4630) 2 DD DD* DD DD D D D D D D D D s s * * s s * D D D D s s * * D D D D 1 D D , D D D D , D D s s1 s s0 * D D D D * 2 D D D D * s s2 s s re 2. (Left) The Ds meson spectrum as predicted by Godfrey and Igsur [12] (solid line) and by Di Pierro and Eichten [13] (dotted li rimental values are shown by points; black points refer to old measured states, red ones to newly discovered. (Right) The charmoni rum. The solid lines are CQM predictions [12], the shaded lines are the observed conventional charmonium states, the horizontal ed lines represent various thresholds. The red dots are the newly discovered charmonium-like states placed in the column of the mo able spin assignment. The states in the last column do not fit elsewhere and appear to be truly exotic. ng list of states, with mass in the range 1–2 GeV/c2, which an exotic interpretation has been claimed. been found, allowing us to check the hyperfine contributi to the q ¯ q potential. Taking the PDG11 [4] value for Mitglied der Helmholtz-Gemeinschaft 28 D Mesons Spectrum Godfrey (2009) »Topics in Hadron Spectroscopy in 2009« arXiv:0910.3409 Predictions Observed New Discoveries Many D(S) and old/new charmonium states decay via D meson → Good reconstruction important! Predictions Observed Gianotti (2012) »Results and perspectives in hadron spectroscopy « Phys. Scr. 2012 014014
47. Mitglied der Helmholtz-Gemeinschaft 29 D Hadronic Decay K∗ 2 (1430)0 → K− π+ K− π+ e+ νe nonresonant < 7 × 10−3 CL=90% 864 K− π+ µ+ νµ ( 3.8 ±0.4 ) % 851 K∗(892)0 µ+ νµ , K∗(892)0 → K− π+ ( 3.52±0.10) % 717 K− π+ µ+ νµ nonresonant ( 2.0 ±0.5 ) × 10−3 851 K− π+ π0 µ+ νµ < 1.6 × 10−3 CL=90% 825 π0 e+ νe ( 4.05±0.18) × 10−3 930 ηe+ νe ( 1.14±0.10) × 10−3 855 ρ0 e+ νe ( 2.18+0.17 −0.25) × 10−3 774 ρ0 µ+ νµ ( 2.4 ±0.4 ) × 10−3 770 ωe+ νe ( 1.82±0.19) × 10−3 771 η′(958)e+ νe ( 2.2 ±0.5 ) × 10−4 689 φe+ νe < 9 × 10−5 CL=90% 657 Fractions of some of the following modes with resonances have already appeared above as submodes of particular charged-particle modes. K∗(892)0 e+ νe ( 5.52±0.15) % 722 K∗(892)0 µ+ νµ ( 5.28±0.15) % 717 K∗ 0 (1430)0 µ+ νµ < 2.4 × 10−4 CL=90% 380 K∗(1680)0 µ+ νµ < 1.5 × 10−3 CL=90% 105 Hadronic modes with a K or K K K Hadronic modes with a K or K K K Hadronic modes with a K or K K K Hadronic modes with a K or K K K K0 S π+ ( 1.47±0.07) % S=2.0 863 K0 L π+ ( 1.46±0.05) % 863 K− 2π+ [c] ( 9.13±0.19) % 846 (K− π+)S−wave π+ ( 7.32±0.19) % 846 K∗ 0 (1430)0 π+ , K∗ 0 (1430)0 → K− π+ [d] ( 1.21±0.06) % 382 HTTP://PDG.LBL.GOV Page 3 Created: 8/21/2014 13:13 D+ D- K-
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    - p p 100 m pBeam = 6.5 GeV/c
48. D+ D- K-
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    - → R p p 100 m 2015-01-15 19:08:40 R| / mm ∆ | 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 5 counts 10 2 10 3 10 4 10 5 10 Entries 1000000 Mean 0.5471 RMS 0.5424 R| ∆ | - D + D 2015-01-15 19:08:42 / mm xy R) ∆ ( 0 0.05 0.1 0.15 0.2 0.25 0.3 counts 0 10000 20000 30000 40000 50000 Entries 1000000 Mean 0.04196 RMS 0.03302 xy R) ∆ ( - D + D 2015-01-15 19:08:41 / mm z R) ∆ ( 5 − 4 − 3 − 2 − 1 − 0 1 2 3 4 5 counts 0 10000 20000 30000 40000 50000 60000 70000 80000 Entries 1000000 Mean 0.001421 − RMS 0.7685 z R) ∆ ( - D + D Mitglied der Helmholtz-Gemeinschaft D Decay Vertex Distances 30
49. D+ D- K-
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    - p p 100 m CHAPTER 4. APPLICATION TO THE RECONSTRUCTION OF D+ ! K ⇡+⇡+ 2015-01-15 19:08:22 ) 4 /c 2 / (GeV (1+2) + π - K 2 M 0.5 1 1.5 2 2.5 3 ) 4 /c 2 counts / 0.03 (GeV 0 10000 20000 30000 40000 50000 Entries 2000000 Daughters Invariant Mass + D (a) m2(K ⇡+). Two entries per event, as the two final state ⇡ are indistinguishable. 2015-01-15 19:08:23 ) 4 /c 2 / (GeV (2) + π (1) + π 2 M 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 ) 4 /c 2 counts / 0.02 (GeV 0 2000 4000 6000 8000 10000 12000 14000 Entries 1000000 Daughters Invariant Mass + D (b) m2(⇡+⇡+) Figure 4.7: Squared masses of the two two-particle-combinations of the D+ daughter particles. 4.6. BACKGROUND STUDIES Figure 4.5: Momenta Plots from CLEO-c. The corresponding plots of EvtGen’s implementation are Figure 4.6, Figure 4.7(a), and Figure 4.7(b). NOTE: Ref! ) 4 /c 2 ) / (GeV ) 2.5 3 Entries 1000000 350 400 450 Entries 1000000 + π + π - K → + Dalitz plot for D CHAPTER 4. APPLICATION TO THE RECONSTRUCTION OF D+ ! K ⇡+⇡ 2015-01-15 19:08:22 ) 4 /c 2 / (GeV (1+2) + π - K 2 M 0.5 1 1.5 2 2.5 3 ) 4 /c 2 counts / 0.03 (GeV 0 10000 20000 30000 40000 50000 Entries 2000000 Daughters Invariant Mass + D (a) m2(K ⇡+). Two entries per event, as the two final state ⇡ are indistinguishable. 2015-01-15 19:08:23 ) 4 /c 2 / (GeV (2) + π (1) + π 2 M 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 ) 4 /c 2 counts / 0.02 (GeV 0 2000 4000 6000 8000 10000 12000 14000 Entries 1000000 Daughters Invariant Mass + D (b) m2(⇡+⇡+) Figure 4.7: Squared masses of the two two-particle-combinations of the D+ daughter particles. Mitglied der Helmholtz-Gemeinschaft Decay Model: EvtGen / CLEO 31 CLEO-c EvtGen 4.6. BACKGROUND STUDIES Figure 4.5: Momenta Plots from CLEO-c. The corresponding plots of EvtGen’s implementation are Figure 4.6, Figure 4.7(a), and Figure 4.7(b). NOTE: Ref! 2014-12-21 20:29:11 ) 4 /c 2 ) / (GeV (1) + π - (K 2 m 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 ) 4 /c 2 ) / (GeV (2) + π - (K 2 m 1 1.5 2 2.5 3 Entries 1000000 0 50 100 150 200 250 300 350 400 450 Entries 1000000 + π + π - K → + Dalitz plot for D Figure 4.6: Dalitz plot for D+ ! K ⇡+⇡+. Since the two ⇡ in the final state are indistinguishable, the distribution is symmetric around the diagonal y = x. K ⇡+ (1) is the lighter combination, plotted on x.
50. 2015-01-07 14:34:50 / GeV/c z p 0 0.5 1 1.5 2 2.5 3 3.5 / GeV/c t p 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Entries 2000000 0 200 400 600 800 1000 1200 1400 Entries 2000000 Momentum Distribution (1+2) + π Mitglied der Helmholtz-Gemeinschaft K, π Momentum Distributions 32 2015-01-07 14:34:42 / GeV/c z p 0 0.5 1 1.5 2 2.5 3 3.5 / GeV/c t p 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Entries 1000000 0 100 200 300 400 500 Entries 1000000 Momentum Distribution - K
51. Mitglied der Helmholtz-Gemeinschaft D± → K∓ π± π± 33 Description & EvtGen Detector Response Tracking Performance Event Reconstruction
52. 2015-01-27 14:49:51 #Hits 0 10 20 30 40 50 60 70 80 counts 0 10000 20000 30000 40000 50000 60000 Entries 200000 Mean 0.02411 ± 12.23 RMS 0.01705 ± 10.78 Underflow 0 Overflow 0 : #STT Hits - K 2015-01-28 20:29:58 #Hits 0 10 20 30 40 50 60 counts 1 10 2 10 3 10 4 10 5 10 Entries 200000 Mean 0.02405 ± 3.443 RMS 0.01701 ± 10.76 Underflow 0 Overflow 0 : #FTS Hits - K Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 34 2015-01-24 16:10:55 #Hits 0 1 2 3 4 5 6 7 8 counts 0 20 40 60 80 100 3 10 × Entries 200000 Mean 0.006149 ± 2.342 RMS 0.004348 ± 2.75 Underflow 0 Overflow 0 : #GEM Hits - K 2015-01-24 16:10:54 #Hits 0 1 2 3 4 5 6 7 8 9 counts 0 10000 20000 30000 40000 50000 60000 Entries 200000 Mean 0.003445 ± 3.671 RMS 0.002436 ± 1.541 Underflow 0 Overflow 0 : #MVD Hits - K K- MVD STT GEM FTS
53. 2015-01-28 20:39:59 #GEM Hits 0 1 2 3 4 5 6 7 8 #STT Hits 0 5 10 15 20 25 30 Entries 200000 Mean x 0.006153 ± 2.343 Mean y 0.02403 ± 12.2 RMS x 0.004351 ± 2.751 RMS y 0.01699 ± 10.74 0 185 0 0 199815 0 0 0 0 0 5000 10000 15000 20000 25000 30000 Entries 200000 Mean x 0.006153 ± 2.343 Mean y 0.02403 ± 12.2 RMS x 0.004351 ± 2.751 RMS y 0.01699 ± 10.74 0 185 0 0 199815 0 0 0 0 : #GEM Hits vs. #STT Hits - K Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 35 K- STT GEM
54. 2015-01-24 16:11:25 #Hits 0 1 2 3 4 5 6 7 8 counts 0 50 100 150 200 250 3 10 × Entries 400000 Mean 0.003999 ± 1.647 RMS 0.002828 ± 2.529 Underflow 0 Overflow 8 : #GEM Hits + π 2015-01-24 16:11:24 #Hits 0 1 2 3 4 5 6 7 8 9 counts 0 20 40 60 80 100 120 3 10 × Entries 400000 Mean 0.002305 ± 3.815 RMS 0.00163 ± 1.458 Underflow 0 Overflow 41 : #MVD Hits + π Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 36 π+ 2015-01-28 20:30:27 #Hits 0 10 20 30 40 50 60 70 80 counts 0 10000 20000 30000 40000 50000 60000 70000 Entries 400000 Mean 0.01823 ± 17.59 RMS 0.01289 ± 11.51 Underflow 0 Overflow 1132 : #STT Hits + π 2015-01-28 20:33:00 #Hits 0 10 20 30 40 50 60 counts 1 10 2 10 3 10 4 10 5 10 Entries 400000 Mean 0.0152 ± 2.582 RMS 0.01075 ± 9.612 Underflow 0 Overflow 12 : #FTS Hits + π MVD STT GEM FTS
55. 2015-01-25 17:09:12 / GeV/c z p 0 0.5 1 1.5 2 2.5 3 3.5 / GeV/c t p 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Entries 70379 Mean x 0.003239 ± 1.435 Mean y 0.0007536 ± 0.3081 RMS x 0.00229 ± 0.8592 RMS y 0.0005329 ± 0.1999 0 0 0 0 70379 0 0 0 0 0 20 40 60 80 100 120 Entries 70379 Mean x 0.003239 ± 1.435 Mean y 0.0007536 ± 0.3081 RMS x 0.00229 ± 0.8592 RMS y 0.0005329 ± 0.1999 0 0 0 0 70379 0 0 0 0 for no #STT Hits z vs. p t : p + π 2015-01-25 17:09:13 / GeV/c z p 0 0.5 1 1.5 2 2.5 3 3.5 / GeV/c t p 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Entries 34085 Mean x 0.004096 ± 0.962 Mean y 0.001204 ± 0.3999 RMS x 0.002896 ± 0.7562 RMS y 0.0008514 ± 0.2223 0 0 0 0 34085 0 0 0 0 0 20 40 60 80 100 Entries 34085 Mean x 0.004096 ± 0.962 Mean y 0.001204 ± 0.3999 RMS x 0.002896 ± 0.7562 RMS y 0.0008514 ± 0.2223 0 0 0 0 34085 0 0 0 0 for no #STT, #GEM, #FTS Hits z vs. p t : p + π 2015-01-25 17:09:13 #FTS Hits 0 10 20 30 40 50 60 #GEM Hits 0 1 2 3 4 5 6 7 8 Entries 70379 Mean x 0.06796 ± 12.04 Mean y 0.01082 ± 2.685 RMS x 0.04805 ± 18.03 RMS y 0.007649 ± 2.869 0 1 0 0 70376 2 0 0 0 0 5000 10000 15000 20000 25000 30000 Entries 70379 Mean x 0.06796 ± 12.04 Mean y 0.01082 ± 2.685 RMS x 0.04805 ± 18.03 RMS y 0.007649 ± 2.869 0 1 0 0 70376 2 0 0 0 : #Hits FTS vs. #Hits GEM for no #Hits STT + π Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 37 π+: No STT hits 2015-01-28 20:30:27 #Hits 0 10 20 30 40 50 60 70 80 counts 0 10000 20000 30000 40000 50000 60000 70000 Entries 400000 Mean 0.01823 ± 17.59 RMS 0.01289 ± 11.51 Underflow 0 Overflow 1132 : #STT Hits + π STT GEM FTS STT STT STT GEM FTS MVD
56. 2015-01-30 11:41:07 θ 0 0.5 1 1.5 2 2.5 3 #Hits per track 0 5 10 15 20 25 30 35 40 Sub-Detectors MVD STT GEM FTS ALL for Different Sub-Detectors θ : Profile of #Hits vs. + π 2015-01-30 11:40:42 θ 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2 #Hits per track 0 5 10 15 20 25 30 Sub-Detectors MVD STT GEM FTS ALL for Different Sub-Detectors θ : Profile of #Hits vs. - K Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 38 π & K: Profile histogram comparison
57. 2015-02-01 20:24:34 θ 0 0.5 1 1.5 2 2.5 3 #Hits > 6 / #Hits 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 (All Sub-Detectors) θ : Efficiency vs. + π 2015-02-01 20:24:03 θ 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 #Hits > 6 / #Hits 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 (All Sub-Detectors) θ : Efficiency vs. - K Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 39 π: Efficiency estimation Tracks with more than 6 hits All tracks All All
58. Mitglied der Helmholtz-Gemeinschaft Decay Positions 40 K 2015-02-01 20:37:11 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 1 10 2 10 3 10 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 K: Decay Positions r vs. z All
59. 2015-02-01 20:37:11 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 1 10 2 10 3 10 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 K: Decay Positions r vs. z Mitglied der Helmholtz-Gemeinschaft Decay Positions 41 2015-02-01 20:37:17 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 1 10 2 10 3 10 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 : Decay Positions r vs. z π K & π All All
60. 2015-02-01 20:37:11 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 1 10 2 10 3 10 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 K: Decay Positions r vs. z Mitglied der Helmholtz-Gemeinschaft Decay Positions 41 2015-02-01 20:37:17 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 1 10 2 10 3 10 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 : Decay Positions r vs. z π 2015-02-01 20:37:13 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 1 10 2 10 3 10 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 K: Decay Positions r vs. z 2015-02-01 20:37:18 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 1 10 2 10 3 10 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 : Decay Positions r vs. z π K & π All All
61. 2015-02-01 20:37:11 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 1 10 2 10 3 10 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 K: Decay Positions r vs. z Mitglied der Helmholtz-Gemeinschaft Decay Positions 41 2015-02-01 20:37:17 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 1 10 2 10 3 10 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 : Decay Positions r vs. z π 2015-02-01 20:37:13 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 1 10 2 10 3 10 Entries 382674 Mean x 0.306 ± 205.9 Mean y 0.05362 ± 54.9 RMS x 0.2164 ± 189.3 RMS y 0.03791 ± 33.16 0 66 4 0 382551 53 0 0 0 K: Decay Positions r vs. z 2015-02-01 20:37:18 z / cm 0 200 400 600 800 1000 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 1 10 2 10 3 10 Entries 762146 Mean x 0.203 ± 161.2 Mean y 0.03335 ± 60.81 RMS x 0.1436 ± 177.2 RMS y 0.02358 ± 29.11 0 59 3 163 761890 31 0 0 0 : Decay Positions r vs. z π K & π 2015-02-01 20:37:16 θ 0 0.5 1 1.5 2 2.5 3 ratio of counts inside / all 0 0.2 0.4 0.6 0.8 1 K: Ratio of IN / ALL of DIRC/EMC 2015-02-01 20:37:22 θ 0 0.5 1 1.5 2 2.5 3 ratio of counts inside / all 0.2 0.4 0.6 0.8 1 : Ratio of IN / ALL of DIRC/EMC π All All
62. 2015-01-25 18:00:32 z / cm 100 − 0 100 200 300 400 500 600 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 33385 Mean x 0.3767 ± 38.3 Mean y 0.1691 ± 17.86 RMS x 0.2664 ± 68.8 RMS y 0.1196 ± 30.88 0 12 0 16 33354 3 0 0 0 0 200 400 600 800 1000 1200 1400 Entries 33385 Mean x 0.3767 ± 38.3 Mean y 0.1691 ± 17.86 RMS x 0.2664 ± 68.8 RMS y 0.1196 ± 30.88 0 12 0 16 33354 3 0 0 0 : Decay Positions r vs. z for no #STT, #GEM, #FTS Hits + π Mitglied der Helmholtz-Gemeinschaft Decay Positions 42 π+: Positions for no STT, no GEM, no FTS hits Particles go through uncovered slits! STT GEM FTS MVD
63. 2015-01-25 18:00:32 z / cm 100 − 0 100 200 300 400 500 600 r / cm 0 20 40 60 80 100 120 140 160 180 200 220 Entries 33385 Mean x 0.3767 ± 38.3 Mean y 0.1691 ± 17.86 RMS x 0.2664 ± 68.8 RMS y 0.1196 ± 30.88 0 12 0 16 33354 3 0 0 0 0 200 400 600 800 1000 1200 1400 Entries 33385 Mean x 0.3767 ± 38.3 Mean y 0.1691 ± 17.86 RMS x 0.2664 ± 68.8 RMS y 0.1196 ± 30.88 0 12 0 16 33354 3 0 0 0 : Decay Positions r vs. z for no #STT, #GEM, #FTS Hits + π Mitglied der Helmholtz-Gemeinschaft Decay Positions 42 π+: Positions for no STT, no GEM, no FTS hits Particles go through uncovered slits! STT GEM FTS MVD
64. Mitglied der Helmholtz-Gemeinschaft D± → K∓ π± π± 43 Description & EvtGen Detector Response Tracking Performance Event Reconstruction
65. 2015-02-02 14:42:50 θ 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 ε 0 0.2 0.4 0.6 0.8 1 Particles All ± K ± π θ vs. ε Reconstruction efficiency 2015-02-02 14:46:07 θ 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 ε 0 0.2 0.4 0.6 0.8 1 Particles All ± K ± π θ vs. ε Reconstruction efficiency Mitglied der Helmholtz-Gemeinschaft Circle Hough Benchmark 44 εAll = 97 % εK = 82 % επ = 95 % K, π: Efficiency of reconstructable tracks εAll = 81 % εK = 71 % επ = 82 % PANDA default tracking Circle Hough
66. 2015-01-28 19:29:48 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 50 100 150 200 250 300 Entries 2076 Mean 0.002905 ± 0.01168 − RMS 0.002054 ± 0.1323 / ndf 2 χ 306.5 / 64 Constant 8.6 ± 213.9 Mean 0.001599 ± 0.008731 − Sigma 0.00213 ± 0.06589 Particles ± Transverse Momentum Relative: #K 2015-01-28 19:29:46 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 100 200 300 400 500 600 700 800 900 Entries 5268 Mean 0.001937 ± 0.02164 − RMS 0.001369 ± 0.14 / ndf 2 χ 865 / 83 Constant 17.0 ± 682 Mean 0.00078 ± 0.01069 − Sigma 0.00101 ± 0.05104 Particles ± π Transverse Momentum Relative: 2015-01-28 19:27:47 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 100 200 300 400 500 600 Entries 2396 Mean 0.004085 ± 0.04415 − RMS 0.002889 ± 0.1973 / ndf 2 χ 526.1 / 87 Constant 21.0 ± 611.8 Mean 0.000558 ± 0.004154 − Sigma 0.00059 ± 0.02356 Particles ± Transverse Momentum Relative: #K 2015-01-28 19:27:46 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 200 400 600 800 1000 1200 1400 1600 1800 Entries 6118 Mean 0.002647 ± 0.03134 − RMS 0.001872 ± 0.2032 / ndf 2 χ 1447 / 96 Constant 39.8 ± 1846 Mean 0.000288 ± 0.001895 − Sigma 0.00030 ± 0.01922 Particles ± π Transverse Momentum Relative: Mitglied der Helmholtz-Gemeinschaft Circle Hough Benchmark 45 K, π: pt resolution σAll = 5.5 % σK = 6.5 % σπ = 5.1 % σAll = 2.1 % σK = 2.3 % σπ = 1.9 % σAll = 5.4 % σK = 5.6 % σπ = 5.2 % PANDA default tracking Circle Hough PANDA tracking w/o Kalman
67. Spurious found tracks: Partially found tracks Mitglied der Helmholtz-Gemeinschaft Circle Hough Benchmark 46 pt resolution of differently well-found tracks Fully found tracks • All hits of reconstructed track come from one MC track • ≥ 50 % of hits of MC track are in reconstructed track • ≥ 50 % hits of reconstructed track come from one MC track • All hits of reconstructed track come from one MC track • All hits of MC track are in reconstructed track 2015-01-28 19:29:49 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 100 200 300 400 500 600 Entries 3153 Mean 0.001133 ± 0.005316 − RMS 0.000801 ± 0.06361 / ndf 2 χ 261.2 / 33 Constant 14.1 ± 487.3 Mean 0.000882 ± 0.008452 − Sigma 0.00105 ± 0.04735 Transverse Momentum Relative: All, fully 2015-01-28 19:29:49 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 10 20 30 40 50 Entries 617 Mean 0.006823 ± 0.002804 − RMS 0.004825 ± 0.1691 / ndf 2 χ 95.64 / 50 Constant 2.26 ± 34.85 Mean 0.00568 ± 0.01461 − Sigma 0.0057 ± 0.1187 Transverse Momentum Relative: All, Partially 2015-01-28 19:29:50 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 50 100 150 200 250 300 350 400 450 Entries 2807 Mean 0.002806 ± 0.01998 − RMS 0.001984 ± 0.1478 / ndf 2 χ 497.5 / 79 Constant 11.8 ± 351.8 Mean 0.00108 ± 0.01299 − Sigma 0.00134 ± 0.05168 Transverse Momentum Relative: All, Spurious (>0.7) 7 % 2.1 % 13.7 % PANDA default tracking Circle Hough PANDA tracking w/o Kalman σpt N 11.9 % 11 % 11 % 41 % 5.1 % 7.4 % σpt N 5.1 % 36 % 36 % 34 % 1.8 % 4.1 % σpt N 4.7 % 47 % 47 %
68. Spurious found tracks: Mitglied der Helmholtz-Gemeinschaft Circle Hough Benchmark 47 pt resolution of differently well-found tracks • ≥ 50 % hits of reconstructed track come from one MC track 2015-01-28 19:29:50 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 50 100 150 200 250 300 350 400 450 Entries 2807 Mean 0.002806 ± 0.01998 − RMS 0.001984 ± 0.1478 / ndf 2 χ 497.5 / 79 Constant 11.8 ± 351.8 Mean 0.00108 ± 0.01299 − Sigma 0.00134 ± 0.05168 Transverse Momentum Relative: All, Spurious (>0.7) PANDA default tracking Circle Hough PANDA tracking w/o Kalman 41 % 5.1 % 7.4 % σpt N 5.1 % 36 % 36 % 2015-01-28 19:29:50 fraction (a.u.) 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 counts 0 20 40 60 80 100 120 140 160 180 Entries 3821 Mean 0.002095 ± 0.7873 RMS 0.001481 ± 0.1295 Fraction of Hits of a MC Track in Assoc. Reco Track
69. Spurious found tracks: Mitglied der Helmholtz-Gemeinschaft Circle Hough Benchmark 47 pt resolution of differently well-found tracks • ≥ 50 % hits of reconstructed track come from one MC track 2015-01-28 19:29:50 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 50 100 150 200 250 300 350 400 450 Entries 2807 Mean 0.002806 ± 0.01998 − RMS 0.001984 ± 0.1478 / ndf 2 χ 497.5 / 79 Constant 11.8 ± 351.8 Mean 0.00108 ± 0.01299 − Sigma 0.00134 ± 0.05168 Transverse Momentum Relative: All, Spurious (>0.7) PANDA default tracking Circle Hough PANDA tracking w/o Kalman 41 % 5.1 % 7.4 % σpt N 5.1 % 36 % 36 % 2015-01-28 19:29:50 fraction (a.u.) 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 counts 0 20 40 60 80 100 120 140 160 180 Entries 3821 Mean 0.002095 ± 0.7873 RMS 0.001481 ± 0.1295 Fraction of Hits of a MC Track in Assoc. Reco Track 2015-01-28 19:29:51 fraction reco'd hits (a.u.) 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 Entries 3821 Mean x 0.002086 ± 0.7925 Mean y 0.003193 ± 0.03289 RMS x 0.001475 ± 0.1269 RMS y 0.002258 ± 0.1942 0 5 10 15 20 25 30 35 40 45 Entries 3821 Mean x 0.002086 ± 0.7925 Mean y 0.003193 ± 0.03289 RMS x 0.001475 ± 0.1269 RMS y 0.002258 ± 0.1942 res. t Fraction of Hits of a MC Track in Assoc. Reco Track vs. p
70. Spurious found tracks: Mitglied der Helmholtz-Gemeinschaft Circle Hough Benchmark 47 pt resolution of differently well-found tracks • ≥ 50 % hits of reconstructed track come from one MC track 2015-01-28 19:29:50 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 50 100 150 200 250 300 350 400 450 Entries 2807 Mean 0.002806 ± 0.01998 − RMS 0.001984 ± 0.1478 / ndf 2 χ 497.5 / 79 Constant 11.8 ± 351.8 Mean 0.00108 ± 0.01299 − Sigma 0.00134 ± 0.05168 Transverse Momentum Relative: All, Spurious (>0.7) PANDA default tracking Circle Hough PANDA tracking w/o Kalman 41 % 5.1 % 7.4 % σpt N 5.1 % 36 % 36 % 2015-01-28 19:29:50 fraction (a.u.) 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 counts 0 20 40 60 80 100 120 140 160 180 Entries 3821 Mean 0.002095 ± 0.7873 RMS 0.001481 ± 0.1295 Fraction of Hits of a MC Track in Assoc. Reco Track 2015-01-28 19:29:51 fraction reco'd hits (a.u.) 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 MC t ) / p MC t - p RECO t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 Entries 3821 Mean x 0.002086 ± 0.7925 Mean y 0.003193 ± 0.03289 RMS x 0.001475 ± 0.1269 RMS y 0.002258 ± 0.1942 0 5 10 15 20 25 30 35 40 45 Entries 3821 Mean x 0.002086 ± 0.7925 Mean y 0.003193 ± 0.03289 RMS x 0.001475 ± 0.1269 RMS y 0.002258 ± 0.1942 res. t Fraction of Hits of a MC Track in Assoc. Reco Track vs. p 2015-02-02 16:06:04 fraction reco'd hits (a.u.) 0.5 0.55 0.6 0.65 0.7 0.75 0.8 0.85 0.9 0.95 1 MC t ) / p MC t - p RECO t (p 0.1 − 0.05 − 0 0.05 0.1 0.15 0.2 0.25 0.3 Entries 3699 Mean 0.002084 ± 0.7925 Mean y 0.003193 ± 0.03276 RMS 0.001474 ± 0.1267 RMS y 0.002258 ± 0.1942 res. t Fraction of Hits of a MC Track in Assoc. Reco Track vs. p
71. 2015-02-02 14:36:57 / GeV/c MC t p 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 ratio ε 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Algorithms Default Circle Hough Efficiency of All MC Tracks vs. Transv. Mom. 2015-02-02 14:36:58 / GeV/c MC t p 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 ratio ε 0 0.2 0.4 0.6 0.8 1 Algorithms Default Circle Hough Efficiency of MC Tracks Possible to Find vs. Transv. Mom. Mitglied der Helmholtz-Gemeinschaft Circle Hough Benchmark 48 Efficiencies vs. pt PANDA default tracking Circle Hough Found tracks All tracks Found tracks Findable tracks
72. Mitglied der Helmholtz-Gemeinschaft D± → K∓ π± π± 49 Description & EvtGen Detector Response Tracking Performance Event Reconstruction
73. Mitglied der Helmholtz-Gemeinschaft Offline Event Analysis • PandaRoot: scrut14 • Beam Momentum: pBeam = 6.5 GeV/c • PID algorithm: PidAlgoIdealCharged • PID selection: {Kaon,Pi}Best{Plus,Minus} • Initial signal dataset: 200 000 events produced • Mass window cut: Δmcut = 0.15 GeV/c2 around mD 50
74. 2015-02-01 16:42:18 Mesons - #D 0 1 2 3 4 5 6 ratio (a.u.) 0 0.05 0.1 0.15 0.2 0.25 0.3 Entries 83512 / event - # D / event + # D D: Percentage of Reconstructed Mesons (before cuts) Mitglied der Helmholtz-Gemeinschaft Offline Analysis — D Mesons / Event 51 • 25 % (30 %) of all events: 1 D+(-) is found • 9 % (12 %) of all events: >1 D+(-) is found no cuts
75. Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Daughter Momenta 52 2015-02-01 16:42:19 / GeV/c z p 0 0.5 1 1.5 2 2.5 3 3.5 / GeV/c t p 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Entries 69987 Mean x 0.002427 ± 1.236 Mean y 0.0008045 ± 0.4365 RMS x 0.001716 ± 0.6412 RMS y 0.0005689 ± 0.2126 1 85 37 43 69809 12 0 0 0 0 5 10 15 20 25 30 35 40 45 Entries 69987 Mean x 0.002427 ± 1.236 Mean y 0.0008045 ± 0.4365 RMS x 0.001716 ± 0.6412 RMS y 0.0005689 ± 0.2126 1 85 37 43 69809 12 0 0 0 ): Momentum Distribution + (from D - K 2015-02-01 16:42:20 / GeV/c z p 0 0.5 1 1.5 2 2.5 3 / GeV/c t p 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Entries 139974 Mean x 0.001737 ± 0.9904 Mean y 0.0004872 ± 0.4571 RMS x 0.001229 ± 0.6485 RMS y 0.0003445 ± 0.1818 0 308 137 105 139299 125 0 0 0 0 10 20 30 40 50 60 70 80 90 100 Entries 139974 Mean x 0.001737 ± 0.9904 Mean y 0.0004872 ± 0.4571 RMS x 0.001229 ± 0.6485 RMS y 0.0003445 ± 0.1818 0 308 137 105 139299 125 0 0 0 ): Momentum Distribution (2 Entries per D) + (from D + Pi no cuts
76. Mitglied der Helmholtz-Gemeinschaft Offline Analysis — D Candidate Mass 53 no cuts 2015-02-01 17:42:20 2 m / GeV/c 1.7 1.75 1.8 1.85 1.9 1.95 2 2.05 counts 0 500 1000 1500 2000 2500 3000 3500 4000 Entries 69987 Mean 0.0001896 ± 1.862 RMS 0.0001341 ± 0.05016 Underflow 0 Overflow 0 : Invariant Mass + D
77. Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Vertex Fit 54 no cuts 2015-02-01 17:42:21 2 χ 0 1 2 3 4 5 6 7 8 9 10 counts 0 200 400 600 800 1000 1200 1400 Entries 69987 Mean 0.009761 ± 2.521 RMS 0.006902 ± 2.142 Underflow 744 Overflow 2.11e+04 2 χ : Vertex Fit + D 2015-02-01 17:42:21 ) 2 χ Prob( 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 counts 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 22000 Entries 69987 Mean 0.001346 ± 0.3888 RMS 0.0009516 ± 0.3556 Underflow 0 Overflow 146 ) 2 χ : Vertex Fit Prob( + D PndKinVtxFit
78. Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Vertex Fit 54 no cuts 2015-02-01 17:42:21 2 χ 0 1 2 3 4 5 6 7 8 9 10 counts 0 200 400 600 800 1000 1200 1400 Entries 69987 Mean 0.009761 ± 2.521 RMS 0.006902 ± 2.142 Underflow 744 Overflow 2.11e+04 2 χ : Vertex Fit + D 2015-02-01 17:42:21 ) 2 χ Prob( 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 counts 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 22000 Entries 69987 Mean 0.001346 ± 0.3888 RMS 0.0009516 ± 0.3556 Underflow 0 Overflow 146 ) 2 χ : Vertex Fit Prob( + D Require Prob(χ2) > 0.01 PndKinVtxFit
79. Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Vertex After Vertex Fit 55 Vertex Fit 2015-02-01 17:42:25 z / cm 0.1 − 0.05 − 0 0.05 0.1 0.15 0.2 0.25 counts 0 200 400 600 800 1000 1200 1400 1600 1800 2000 2200 2400 Entries 69987 Mean 0.0002301 ± 0.05153 RMS 0.0001627 ± 0.05695 Underflow 5395 Overflow 3341 Entries 42207 Mean 0.0002513 ± 0.05143 RMS 0.0001777 ± 0.05111 Underflow 222 Overflow 605 : z Position After Vtx Fit (Comparison) + D 2015-02-01 17:42:23 x / cm 0.1 − 0.08 − 0.06 − 0.04 − 0.02 − 0 0.02 0.04 0.06 0.08 0.1 counts 0 1000 2000 3000 4000 5000 6000 Entries 69987 Mean 05 − 8.289e ± 06 − 3.428e RMS 05 − 5.861e ± 0.02081 Underflow 3384 Overflow 3590 Entries 42207 Mean 05 − 5.393e ± 05 − 1.866e − RMS 05 − 3.814e ± 0.01106 Underflow 87 Overflow 96 : x Position After Vtx Fit (Comparison) + D 2015-02-01 17:42:24 y / cm 0.1 − 0.08 − 0.06 − 0.04 − 0.02 − 0 0.02 0.04 0.06 0.08 0.1 counts 0 1000 2000 3000 4000 5000 6000 Entries 69987 Mean 05 − 8.361e ± 05 − 1.227e RMS 05 − 5.912e ± 0.02101 Underflow 3434 Overflow 3395 Entries 42207 Mean 05 − 5.304e ± 06 − 4.617e RMS 05 − 3.75e ± 0.01087 Underflow 99 Overflow 110 : y Position After Vtx Fit (Comparison) + D no cuts
80. Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Mass After Vertex Fit 56 no cuts Vertex Fit 2015-02-01 18:13:26 2 ) / GeV/c MC (m - m 0.15 − 0.1 − 0.05 − 0 0.05 0.1 0.15 counts 0 500 1000 1500 2000 2500 3000 3500 4000 Entries 69987 Mean 0.0001858 ± 0.007714 − RMS 0.0001314 ± 0.04639 Underflow 1468 Overflow 6176 / ndf 2 χ 1.241e+04 / 97 Constant 24.8 ± 3255 Mean 0.000100 ± 0.002007 − Sigma 0.00014 ± 0.02204 Entries 42207 Mean 0.0001669 ± 0.003508 − RMS 0.000118 ± 0.03381 Underflow 98 Overflow 1055 / ndf 2 χ 4654 / 94 Constant 22.4 ± 2882 Mean 0.000098 ± 0.001167 − Sigma 0.00010 ± 0.01814 : Relative Invariant Mass After Vertex Fit Comparison + D 2015-02-01 18:16:44 ) / GeV/c MC t - p t (p 1 − 0.8 − 0.6 − 0.4 − 0.2 − 0 0.2 0.4 0.6 0.8 1 counts 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 20000 22000 Entries 69987 Mean 0.0005834 ± 0.0542 RMS 0.0004125 ± 0.1531 Underflow 0 Overflow 1106 / ndf 2 χ 1.764e+04 / 55 Constant 1.520e+02 ± 2.379e+04 Mean 0.000077 ± 0.001102 Sigma 0.00008 ± 0.01719 Entries 42207 Mean 0.0009259 ± 0.01594 RMS 0.0006547 ± 0.1873 Underflow 0 Overflow 1284 / ndf 2 χ 5474 / 97 Constant 23.3 ± 2732 Mean 0.000551 ± 0.003463 Sigma 0.0007 ± 0.1035 : Relative Transverse Momentum After Vertex Fit Comparison + D
81. 2015-02-01 18:16:45 2 χ 0 1 2 3 4 5 6 7 8 9 10 counts 0 2000 4000 6000 8000 10000 12000 Entries 69987 Mean 0.008903 ± 1.501 RMS 0.006295 ± 2.094 Underflow 219 Overflow 1.443e+04 2 χ : Mass Fit + D 2015-02-01 18:16:45 ) 2 χ Prob( 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 counts 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Entries 69987 Mean 0.001257 ± 0.3587 RMS 0.0008885 ± 0.3321 Underflow 0 Overflow 142 ) 2 χ : Mass Fit Prob( + D Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Mass Constraint Fit 57 no cuts PndKinFitter with D+ mass constraint
82. 2015-02-01 18:16:45 2 χ 0 1 2 3 4 5 6 7 8 9 10 counts 0 2000 4000 6000 8000 10000 12000 Entries 69987 Mean 0.008903 ± 1.501 RMS 0.006295 ± 2.094 Underflow 219 Overflow 1.443e+04 2 χ : Mass Fit + D 2015-02-01 18:16:45 ) 2 χ Prob( 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 counts 0 2000 4000 6000 8000 10000 12000 14000 16000 18000 Entries 69987 Mean 0.001257 ± 0.3587 RMS 0.0008885 ± 0.3321 Underflow 0 Overflow 142 ) 2 χ : Mass Fit Prob( + D Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Mass Constraint Fit 57 no cuts Require Prob(χ2) > 0.01 PndKinFitter with D+ mass constraint
83. 2015-02-01 18:35:24 2 ) / GeV/c MC (m - m 0.15 − 0.1 − 0.05 − 0 0.05 0.1 0.15 counts 0 500 1000 1500 2000 2500 3000 3500 4000 4500 Entries 69987 Mean 0.0001816 ± 0.007284 − RMS 0.0001284 ± 0.04597 Underflow 0 Overflow 5940 / ndf 2 χ 1.312e+04 / 81 Constant 25.5 ± 3265 Mean 0.000101 ± 0.002073 − Sigma 0.0001 ± 0.0224 Entries 42207 Mean 0.0001669 ± 0.003508 − RMS 0.000118 ± 0.03381 Underflow 98 Overflow 1055 / ndf 2 χ 4654 / 94 Constant 22.4 ± 2882 Mean 0.000098 ± 0.001167 − Sigma 0.00010 ± 0.01814 Entries 45375 Mean 0.0001155 ± 0.001035 − RMS 05 − 8.169e ± 0.024 Underflow 117 Overflow 2095 / ndf 2 χ 1609 / 93 Constant 22.1 ± 3388 Mean 0.0000866 ± 0.0009225 − Sigma 0.00008 ± 0.01762 Entries 35182 Mean 0.0001144 ± 0.0006527 − RMS 05 − 8.09e ± 0.02126 Underflow 50 Overflow 583 / ndf 2 χ 969.4 / 90 Constant 21.3 ± 2940 Mean 0.0000897 ± 0.0007204 − Sigma 0.00008 ± 0.01641 : Relative Mass After Fits Comparison + D Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Mass Constraint Fit 58 • In 17.5 % (20.5 %) of all events: D+ (D-) is found • In 8.6 % of all events: D+D- are found • DPM: Of 1M events, 100 survive these fits → more cuts! no cuts Vertex Fit Mass Fit 2015-02-02 11:24:43 2 ) / GeV/c MC (m - m 0.15 − 0.1 − 0.05 − 0 0.05 0.1 0.15 counts 0 500 1000 1500 2000 2500 3000 3500 4000 4500 Entries 69987 Mean 0.0001816 ± 0.007284 − RMS 0.0001284 ± 0.04597 Underflow 0 Overflow 5940 / ndf 2 χ 1.312e+04 / 81 Constant 25.5 ± 3265 Mean 0.000101 ± 0.002073 − Sigma 0.0001 ± 0.0224 Entries 42207 Mean 0.0001669 ± 0.003508 − RMS 0.000118 ± 0.03381 Underflow 98 Overflow 1055 / ndf 2 χ 4654 / 94 Constant 22.4 ± 2882 Mean 0.000098 ± 0.001167 − Sigma 0.00010 ± 0.01814 Entries 45375 Mean 0.0001155 ± 0.001035 − RMS 05 − 8.169e ± 0.024 Underflow 117 Overflow 2095 / ndf 2 χ 1609 / 93 Constant 22.1 ± 3388 Mean 0.0000866 ± 0.0009225 − Sigma 0.00008 ± 0.01762 Entries 35182 Mean 0.0001144 ± 0.0006527 − RMS 05 − 8.09e ± 0.02126 Underflow 50 Overflow 583 / ndf 2 χ 969.4 / 90 Constant 21.3 ± 2940 Mean 0.0000897 ± 0.0007204 − Sigma 0.00008 ± 0.01641 : Relative Mass After Fits Comparison + D Mass & Vtx
84. Mitglied der Helmholtz-Gemeinschaft Offline Analysis — Inclusive Event 59 • When a D+ is found, the invariant missing mass is at: µ = (1.870 ± 0.0009) GeV/c2 , σ = (0.01676 ± 0.00009) GeV/c2 • PDG: 1.869 GeV/c2 no cuts Vertex Fit 2015-02-02 11:24:48 2 m / GeV/c 1.7 1.75 1.8 1.85 1.9 1.95 2 2.05 counts 0 500 1000 1500 2000 2500 3000 3500 4000 Entries 69987 Mean 0.0001811 ± 1.871 RMS 0.0001281 ± 0.04629 Underflow 4485 Overflow 169 / ndf 2 χ 1.262e+04 / 93 Constant 24.4 ± 3066 Mean 0.000 ± 1.872 Sigma 0.000 ± 0.024 Entries 42207 Mean 0.0001673 ± 1.871 RMS 0.0001183 ± 0.03388 Underflow 1086 Overflow 117 / ndf 2 χ 4516 / 96 Constant 21.4 ± 2741 Mean 0.000 ± 1.871 Sigma 0.00011 ± 0.01858 Entries 35182 Mean 0.0001217 ± 1.869 RMS 05 − 8.606e ± 0.02265 Underflow 472 Overflow 68 / ndf 2 χ 1159 / 96 Constant 20.5 ± 2790 Mean 0.00 ± 1.87 Sigma 0.00008 ± 0.01676 : Inclusive Missing Mass After Fits Comparison + D Mass & Vtx
85. Mitglied der Helmholtz-Gemeinschaft Summary • GPU Algorithms: – Different algorithms in development – Triplet Finder: Max performance 12 MHit/s – Circle Hough: ≥ 70 % reconstruction performance • Benchmark channel D → K π π – 17.5 % D+ can be reconstructed (37 % before fits) ~1300 D+ / h (σ = 100 nb) → Continue studies (Background, Circle Hough) 60
86. Thank you! Andreas Herten a.herten@fz-juelich.de Mitglied der Helmholtz-Gemeinschaft Summary • GPU Algorithms: – Different algorithms in development – Triplet Finder: Max performance 12 MHit/s – Circle Hough: ≥ 70 % reconstruction performance • Benchmark channel D → K π π – 17.5 % D+ can be reconstructed (37 % before fits) ~1300 D+ / h (σ = 100 nb) → Continue studies (Background, Circle Hough) 60
87. Mitglied der Helmholtz-Gemeinschaft BACKUP 61
88. Mitglied der Helmholtz-Gemeinschaft STT — Drift Tubes and t0 62
89. Mitglied der Helmholtz-Gemeinschaft STT — Drift Tubes and t0 62 Particle ionizes gas atoms in drift tubes
90. Mitglied der Helmholtz-Gemeinschaft STT — Drift Tubes and t0 62 Particle ionizes gas atoms in drift tubes Electrons drift to anode wire, ions to wall
91. Mitglied der Helmholtz-Gemeinschaft STT — Drift Tubes and t0 62 Particle ionizes gas atoms in drift tubes Electrons drift to anode wire, ions to wall Signal only when electrons arrive at wire No information about drift duration! For that, start time (t0) needed: t0 - tarrival ≈ tdrift vdrift = const → tdrift • vdrift = risochrone
92. Mitglied der Helmholtz-Gemeinschaft STT — Drift Tubes and t0 62 Particle ionizes gas atoms in drift tubes Electrons drift to anode wire, ions to wall Signal only when electrons arrive at wire No information about drift duration! For that, start time (t0) needed: t0 - tarrival ≈ tdrift vdrift = const → tdrift • vdrift = risochrone risochrone
93. Mitglied der Helmholtz-Gemeinschaft STT — Drift Tubes and t0 62 Particle ionizes gas atoms in drift tubes Resolution without t0: (0.1 cm) Resolution with t0: (0.015 cm) Electrons drift to anode wire, ions to wall Signal only when electrons arrive at wire No information about drift duration! For that, start time (t0) needed: t0 - tarrival ≈ tdrift vdrift = const → tdrift • vdrift = risochrone risochrone
94. Mitglied der Helmholtz-Gemeinschaft STT — Drift Tubes and t0 62 Particle ionizes gas atoms in drift tubes Resolution without t0: (0.1 cm) Resolution with t0: (0.015 cm) Usual HEP experiment: t0 by trigger But PANDA has no trigger… Electrons drift to anode wire, ions to wall Signal only when electrons arrive at wire No information about drift duration! For that, start time (t0) needed: t0 - tarrival ≈ tdrift vdrift = const → tdrift • vdrift = risochrone risochrone
95. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method 63 STT More
96. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method 63 STT More
97. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method 63 STT More
98. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method 63 STT More
99. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw 63 STT More
100. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) 63 STT More
101. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) • Combine with 63 STT More
102. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) • Combine with 1.Second STT pivot-cog virtual hit 63 STT More
103. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) • Combine with 1.Second STT pivot-cog virtual hit 63 STT More
104. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) • Combine with 1.Second STT pivot-cog virtual hit 63 STT More
105. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) • Combine with 1.Second STT pivot-cog virtual hit 2.Interaction point 63 Interaction Point STT More
106. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) • Combine with 1.Second STT pivot-cog virtual hit 2.Interaction point • Calculate circle through three points 63 Interaction Point STT More
107. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Method • STT hit in pivot straw • Find surrounding hits → Create virtual hit (triplet) at center of gravity (cog) • Combine with 1.Second STT pivot-cog virtual hit 2.Interaction point • Calculate circle through three points → Track Candidate 63 Interaction Point STT More
108. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Animation 64 Triplet Isochrone early Isochrone early & skewed Isochrone close Isochrone late MVD hit Track timed out Track current
109. Dynamic Parallelism Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Compare data processing strategies 65 1 thread/bunch Calling kernel 1 thread/bunch Calling kernel Triplet Finder 1 thread/bunch Calling kernel 1 block/bunch Joined kernel 1 block/bunch Joined kernel 1 block/bunch Joined kernel TF Stage #1 TF Stage #2 TF Stage #3 TF Stage #4 1 stream/bunch Combining stream 1 stream/bunch Combining stream 1 stream/bunch Calling stream Joined Kernel Host Streams Triplet Finder Triplet Finder CPU GPU TF Stage #1 TF Stage #2 TF Stage #3 TF Stage #4 TF Stage #1 TF Stage #2 TF Stage #3 TF Stage #4
110. Mitglied der Helmholtz-Gemeinschaft 66 Triplet Finder — Data Processing Explanation K20X
111. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Binning: Sector Rows 67 • Sector Row testing – After found track: Hit association not with all hits of current window, but only with subset (first test rows of sector, then hits of row) More
112. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Binning: Sector Rows 67 • Sector Row testing – After found track: Hit association not with all hits of current window, but only with subset (first test rows of sector, then hits of row) More
113. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Binning: Sector Rows 67 • Sector Row testing – After found track: Hit association not with all hits of current window, but only with subset (first test rows of sector, then hits of row) More
114. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Binning: Sector Rows 67 • Sector Row testing – After found track: Hit association not with all hits of current window, but only with subset (first test rows of sector, then hits of row) More
115. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Binning: Sector Rows 67 • Sector Row testing – After found track: Hit association not with all hits of current window, but only with subset (first test rows of sector, then hits of row) More
116. Mitglied der Helmholtz-Gemeinschaft 68 Triplet Finder — Binning: Sector Rows K20X All Tubes (No Binning) Sector-Row Binning
117. Mitglied der Helmholtz-Gemeinschaft 69 Triplet Finder — Binning: Skewlets K20X Skewlet Binning All Skewlets (No Binning)
118. Mitglied der Helmholtz-Gemeinschaft 70 Triplet Finder — AoS vs. SoA K20X struct  {        int  r,  g,  b; }  AoS[N]; struct  {        int  r[N];        int  g[N];        int  b[N]; }  SoA;
119. Mitglied der Helmholtz-Gemeinschaft 71 Triplet Finder — CUDA Versions K20X
120. Mitglied der Helmholtz-Gemeinschaft 72 Triplet Finder — Clock Speed / GPU K40 3004 MHz, 745 MHz / 875 MHz K20X 2600 MHz, 732 MHz / 784 MHz Memory Clock Core Clock GPU Boost
121. Mitglied der Helmholtz-Gemeinschaft 73 Triplet Finder — Comparison to Kepler K20X 750 Ti Kepler Performance: 3.95 TFLOPSsingle Price: 3600 € Maxwell Performance: 1.3 TFLOPSsingle Price: 130 €
122. Mitglied der Helmholtz-Gemeinschaft 74 Triplet Finder — Kepler vs. Maxwell K20X 750 Ti
123. Mitglied der Helmholtz-Gemeinschaft 75 Triplet Finder — Kepler vs. Maxwell Performance per multiprocessor K20X 750 Ti
124. Mitglied der Helmholtz-Gemeinschaft 75 Triplet Finder — Kepler vs. Maxwell Performance per multiprocessor K20X 750 Ti
125. Tesla K40 Tesla K20X GeForce GTX 760 Ti Peak double performance Peak single performance GPU Chipset # CUDA Cores Memory size Memory bandwidth 1.46 TFLOPS 1.31 TFLOPS 0.04 TFLOPS 4.29 TFLOPS 3.95 TFLOPS 1.3 TFLOPS GK110B GK110 GM107 2880 2688 640 12 GB 6 GB 2 GB 288 GByte/s 250 GByte/s 192 GByte/s Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Optimizations • Impact of chipset 76 Source: http://www.nvidia.com/content/tesla/pdf/NVIDIA-Tesla-Kepler-Family-Datasheet.pdf
126. Mitglied der Helmholtz-Gemeinschaft Triplet Finder — Kernel Launch Strategies • Joined Kernel (JK): slowest – High # registers → low occupancy • Dynamic Parallelism (DP) / Host Streams (HS): comparable performance – Performance • HS faster for small # processed hits, DP faster for > 45000 hits • HS stagnates there, while DP continues rising – Limiting factor • High # of required kernel calls • Kernel launch latency • Memcopy – HS more affected by this, because • More PCI-E transfers (launch configurations for kernels) • Less launch throughput, kernel launch latency gets more important • False dependencies of launched kernels – Single CPU thread handles all CUDA streams (Multi-thread possible, but synchronization overhead too high for good performance) – Grid scheduling done on hardware (Grid Management Unit) (DP: software) » False dependencies when N(streams) > N(device connections)=323.5 77 Back
127. Mitglied der Helmholtz-Gemeinschaft 78 ALGORITHMS #2 Hough Transform Riemann Track Finder Triplet Finder
128. Mitglied der Helmholtz-Gemeinschaft 79 Riemann Track Finder — Method • Idea: Don‘t fit lines (in 2D), fit planes (in 3D)! • Create seeds – All possible three hit combinations • Grow seeds to tracks Continuously test next hit if it fits – Use mapping to Riemann paraboloid (+ s-z fit, det. layer) x x x x y z‘ x x x y x x x x y x More on: Seeds; Growing 1 2
129. Mitglied der Helmholtz-Gemeinschaft 80 1 2 3 4 5 1 2 3 4 5 Riemann Algorithm — 1 Triplets 1 Layer number
130. Mitglied der Helmholtz-Gemeinschaft 80 1 2 3 4 5 1 2 3 4 5 Riemann Algorithm — 1 Triplets 1 Layer number
131. Mitglied der Helmholtz-Gemeinschaft 80 1 2 3 4 5 1 2 3 4 5 Riemann Algorithm — 1 Triplets 1 Layer number
132. Mitglied der Helmholtz-Gemeinschaft 80 1 2 3 4 5 21 11 31 1 2 3 4 5 Riemann Algorithm — 1 Triplets 1 Layer number
133. Mitglied der Helmholtz-Gemeinschaft 80 1 2 3 4 5 21 11 31 31 11 41 1 2 3 4 5 Riemann Algorithm — 1 Triplets 1 Layer number
134. Mitglied der Helmholtz-Gemeinschaft 80 1 2 3 4 5 21 11 31 31 11 41 31 11 32 1 2 3 4 5 Riemann Algorithm — 1 Triplets 1 Layer number
135. Mitglied der Helmholtz-Gemeinschaft 80 1 2 3 4 5 21 11 31 31 11 41 31 11 32 1 2 3 4 5 Riemann Algorithm — 1 Triplets 1 Layer number
136. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2
137. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘
138. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid)
139. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid)
140. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid)
141. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid)
142. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid)
143. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid) x
144. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid) x
145. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid) x
146. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid) x
147. Mitglied der Helmholtz-Gemeinschaft 81 Riemann Algorithm — 1 Expansion 2 x x x x y z‘ Expand to z‘ x x x y x Riemann Surface (paraboloid) x
148. Mitglied der Helmholtz-Gemeinschaft 82 Riemann Track Finder — GPU Adaptations CPU GPU
149. Mitglied der Helmholtz-Gemeinschaft 82 Riemann Track Finder — GPU Adaptations CPU GPU 3 loops to generate seeds serially for (int i = 0; i < hitsInLayerOne.size(); i++) { for (int j = 0; j < hitsInLayerTwo.size(); j++) { for (int k = 0; k < hitsInLayerThree.size(); k++) { /* Triplet Generation */ } } } Needed: Mapping of inherent GPU indexing variable to triplet index int ijk = threadIdx.x + blockIdx.x * blockDim.x; nLayerx = 1 2 ⇣p 8x + 1 1 ⌘ pos ( nLayerx ) = 3 pp 3 p 243x2 1 + 27x 32 / 3 + 1 3 p 3 3 pp 3 p 243x2 1 + 27x 1 1
150. Mitglied der Helmholtz-Gemeinschaft 82 Riemann Track Finder — GPU Adaptations CPU GPU 3 loops to generate seeds serially for (int i = 0; i < hitsInLayerOne.size(); i++) { for (int j = 0; j < hitsInLayerTwo.size(); j++) { for (int k = 0; k < hitsInLayerThree.size(); k++) { /* Triplet Generation */ } } } Needed: Mapping of inherent GPU indexing variable to triplet index int ijk = threadIdx.x + blockIdx.x * blockDim.x; nLayerx = 1 2 ⇣p 8x + 1 1 ⌘ pos ( nLayerx ) = 3 pp 3 p 243x2 1 + 27x 32 / 3 + 1 3 p 3 3 pp 3 p 243x2 1 + 27x 1 1 2 Port of CPU code; parallelism on seed base Only easy computations; e.g. 3x3 matrices
151. Mitglied der Helmholtz-Gemeinschaft 82 Riemann Track Finder — GPU Adaptations CPU GPU → 100 × faster than CPU version: ~0.6 ms/event Still needs merging into PandaRoot 3 loops to generate seeds serially for (int i = 0; i < hitsInLayerOne.size(); i++) { for (int j = 0; j < hitsInLayerTwo.size(); j++) { for (int k = 0; k < hitsInLayerThree.size(); k++) { /* Triplet Generation */ } } } Needed: Mapping of inherent GPU indexing variable to triplet index int ijk = threadIdx.x + blockIdx.x * blockDim.x; nLayerx = 1 2 ⇣p 8x + 1 1 ⌘ pos ( nLayerx ) = 3 pp 3 p 243x2 1 + 27x 32 / 3 + 1 3 p 3 3 pp 3 p 243x2 1 + 27x 1 1 2 Port of CPU code; parallelism on seed base Only easy computations; e.g. 3x3 matrices
152. Mitglied der Helmholtz-Gemeinschaft Algorithm: Hough Transform • Idea: Transform (x,y)i → (α,r)ij, find lines via (α,r) space • Solve rij line equation for – Lots of hits (x,y,ρ)i and – Many αj ∈ [0°,360°) each • Fill histogram • Extract track parameters 83 x y x y Mitglied der Helmholtz-Gemeinschaft Hough Transform — Princip → Bin giv r α
153. Mitglied der Helmholtz-Gemeinschaft Algorithm: Hough Transform • Idea: Transform (x,y)i → (α,r)ij, find lines via (α,r) space • Solve rij line equation for – Lots of hits (x,y,ρ)i and – Many αj ∈ [0°,360°) each • Fill histogram • Extract track parameters 83 rij = cos ↵j · xi + sin ↵j · yi + ⇢i i: ~100 hits/event (STT) j: every 0.2° rij: 180 000 x y x y Mitglied der Helmholtz-Gemeinschaft Hough Transform — Princip → Bin giv r α
154. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Granularity 84 • Line Hough around point α = 0°, 2°, 4°, … α = 0°, 2°, 4°, … rij = cos(αj) ⋅ xi + sin(αj) ⋅ yi static slide
155. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Granularity 84 • Line Hough around point α = 0°, 2°, 4°, … α = 0°, 2°, 4°, … rij = cos(αj) ⋅ xi + sin(αj) ⋅ yi static slide
156. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Granularity 84 • Line Hough around point α = 0°, 2°, 4°, … α = 0°, 2°, 4°, … rij = cos(αj) ⋅ xi + sin(αj) ⋅ yi static slide
157. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 85 • Line Hough with isochrones α = 0°, 10°, 20°, … α = 0°, 10°, 20°, … rij ± = cos(αj) ⋅ xi + sin(αj) ⋅ yi ± ρi static slide
158. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 85 • Line Hough with isochrones α = 0°, 10°, 20°, … α = 0°, 10°, 20°, … rij ± = cos(αj) ⋅ xi + sin(αj) ⋅ yi ± ρi static slide
159. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Variations 85 • Line Hough with isochrones α = 0°, 10°, 20°, … α = 0°, 10°, 20°, … rij ± = cos(αj) ⋅ xi + sin(αj) ⋅ yi ± ρi static slide
160. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Remarks 86 ° / α 0 20 40 60 80 100 120 140 160 180 r -30 -20 -10 0 10 20 30 40 HoughHist Entries 9000 Mean x 89.33 Mean y 6.66 RMS x 51.8 RMS y 19.2 0 2 4 6 8 10 12 14 16 18 HoughHist Entries 9000 Mean x 89.33 Mean y 6.66 RMS x 51.8 RMS y 19.2 HT histogram Hill Climber Peakfinding challenging
161. Mitglied der Helmholtz-Gemeinschaft Hough Transform — Remarks 86 ° / α 0 20 40 60 80 100 120 140 160 180 r -30 -20 -10 0 10 20 30 40 houghIt0 Entries 9000 Mean x 89.33 Mean y 6.66 RMS x 51.8 RMS y 19.2 0 2 4 6 8 10 12 14 16 18 houghIt0 Entries 9000 Mean x 89.33 Mean y 6.66 RMS x 51.8 RMS y 19.2 HT histogram ° / α 0 20 40 60 80 100 120 140 160 180 r -30 -20 -10 0 10 20 30 40 houghIt1 Entries 5580 Mean x 89.6 Mean y 9.719 RMS x 51.78 RMS y 18.09 0 2 4 6 8 10 12 14 16 houghIt1 Entries 5580 Mean x 89.6 Mean y 9.719 RMS x 51.78 RMS y 18.09 HT histogram ° / α 0 20 40 60 80 100 120 140 160 180 r -30 -20 -10 0 10 20 30 houghIt2 Entries 2700 Mean x 89.13 Mean y 13.79 RMS x 51.77 RMS y 14.04 0 2 4 6 8 10 12 houghIt2 Entries 2700 Mean x 89.13 Mean y 13.79 RMS x 51.77 RMS y 14.04 HT histogram -40 -30 -20 -10 0 10 20 30 40 0 5 10 15 20 25 30 Iterative Maximum Deleter Peakfinding challenging
162. 2015-01-24 16:11:25 #Hits 0 10 20 30 40 50 60 counts 0 50 100 150 200 250 300 350 3 10 × Entries 400000 Mean 0.0152 ± 2.582 RMS 0.01075 ± 9.612 Underflow 0 Overflow 12 : #FTS Hits + π 2015-01-24 16:11:25 #Hits 0 1 2 3 4 5 6 7 8 counts 0 50 100 150 200 250 3 10 × Entries 400000 Mean 0.003999 ± 1.647 RMS 0.002828 ± 2.529 Underflow 0 Overflow 8 : #GEM Hits + π 2015-01-24 16:11:27 θ 0 0.05 0.1 0.15 0.2 0.25 0.3 0.35 counts 0 100 200 300 400 500 600 700 800 Entries 29006 Mean 0.0003544 ± 0.1155 RMS 0.0002506 ± 0.05849 Underflow 0 Overflow 1768 for #FTS Hits > 0 θ : + π Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 87 π+: θ for no GEM hits and for no FTS hits 2015-01-25 17:09:14 θ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 counts 0 500 1000 1500 2000 2500 3000 3500 4000 Entries 131877 Mean 0.0003124 ± 0.2456 RMS 0.0002209 ± 0.1129 Underflow 0 Overflow 1378 for #GEM Hits > 0 θ : + π
163. 2015-01-25 17:22:23 θ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 #Hits 0 10 20 30 40 50 60 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.0244 ± 3.496 RMS x 0.0003349 ± 0.2102 RMS y 0.01726 ± 10.83 0 0 0 0 196952 3048 0 0 0 0 500 1000 1500 2000 2500 3000 3500 4000 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.0244 ± 3.496 RMS x 0.0003349 ± 0.2102 RMS y 0.01726 ± 10.83 0 0 0 0 196952 3048 0 0 0 θ : #Hits FTS vs. - K Mitglied der Helmholtz-Gemeinschaft Sub-Detector Hit Counting 88 K-: #Hits vs. θ 2015-01-25 17:22:22 θ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 #Hits 0 1 2 3 4 5 6 7 8 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.006209 ± 2.379 RMS x 0.0003349 ± 0.2102 RMS y 0.004391 ± 2.756 0 0 0 0 196952 3048 0 0 0 0 500 1000 1500 2000 2500 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.006209 ± 2.379 RMS x 0.0003349 ± 0.2102 RMS y 0.004391 ± 2.756 0 0 0 0 196952 3048 0 0 0 θ : #Hits GEM vs. - K 2015-01-25 17:22:21 θ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 #Hits 0 1 2 3 4 5 6 7 8 9 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.003475 ± 3.685 RMS x 0.0003349 ± 0.2102 RMS y 0.002457 ± 1.542 0 0 0 0 196952 3048 0 0 0 0 500 1000 1500 2000 2500 3000 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.003475 ± 3.685 RMS x 0.0003349 ± 0.2102 RMS y 0.002457 ± 1.542 0 0 0 0 196952 3048 0 0 0 θ : #Hits MVD vs. - K 2015-01-25 17:22:21 θ 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 #Hits 0 10 20 30 40 50 60 70 80 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.02423 ± 12.16 RMS x 0.0003349 ± 0.2102 RMS y 0.01713 ± 10.75 0 0 0 0 196952 3048 0 0 0 0 500 1000 1500 2000 2500 3000 3500 Entries 200000 Mean x 0.0004736 ± 0.354 Mean y 0.02423 ± 12.16 RMS x 0.0003349 ± 0.2102 RMS y 0.01713 ± 10.75 0 0 0 0 196952 3048 0 0 0 θ : #Hits STT vs. - K
164. Mitglied der Helmholtz-Gemeinschaft 89 D Meson Production Cross Section 6.0 6.5 7.0 7.5 8.0 p lab (GeV/c) 6.0 6.5 7.0 7.5 8.0 p lab (GeV/c) 10-3 10-2 10-1 100 σ tot (µb) pp -> D+ D- FIG. 3: Total reaction cross sections for ¯ pp → D ¯ D as a func- tion of plab , based on baryon-exchange (shaded band) and the quark model (grid). Results obtained in Born approx- imation are indicated by the dotted (baryon-exchange) and Baryon Exchange Model Quark Model p lab (GeV/c) 6.0 6.5 7.0 7.5 8.0 p lab (GeV/c) 10-3 10-2 10-1 100 σ tot (µb) pp -> D+ D- 3: Total reaction cross sections for ¯ pp → D ¯ D as a func- of plab , based on baryon-exchange (shaded band) and uark model (grid). Results obtained in Born approx- on are indicated by the dotted (baryon-exchange) and dotted (quark model) lines, respectively. lab 6.0 6.5 7.0 7.5 8.0 p lab (GeV/c) 10-3 10-2 10-1 100 σ tot (µb) pp -> D+ D- 3: Total reaction cross sections for ¯ pp → D ¯ D as a func- of plab , based on baryon-exchange (shaded band) and uark model (grid). Results obtained in Born approx- on are indicated by the dotted (baryon-exchange) and dotted (quark model) lines, respectively. J. Haidenbauer, G. Krein; Production of charmed pseudoscalar mesons in antiproton-proton annihilation; arXiv:1404.4174 [hep-ph] (04-2014) from Foley et al. [43], Berglund et al. [47], Russ et al. [48], Λ,Σ, Σ(1385) K K N N ✉ ✉ ↔ Λc ,Σc , Σc (2520) D D N N ✉ ✉ FIG. 2: Transition potential for ¯ NN → D ¯ D (right) and ¯ NN → ¯ KK (left), respectively. D ¯ D, ¯ NN = V D ¯ D, ¯ NN + V D ¯ D, ¯ NN G ¯ NN T ¯ NN, ¯ NN , (5) he ¯ NN potential described in Sect. II. Eq. (5) implies that the ¯ NN → D ¯ D transition s effectively evaluated in a DWBA. with inclusion of ISI effects are presented as ig. 3 because we consider several variants of otential as discussed in the previous section. s that the results change drastically once the ded in the calculation. The cross sections for trongly reduced while at the same time those are enhanced. Indeed now both D ¯ D channels d at a comparable rate. In fact, the predicted n for D+D− appears to be even somewhat the one for D0 ¯ D0. the reduction in the D0 ¯ D0 case is in line arable effects observed in the previous stud- annihilation processes [23, 25–27], as men- ve, the enhancement seen for D+D− may be 6.0 6.5 7.0 7. p lab (GeV/c) 10-3 10-2 10-1 100 σ tot (µb) FIG. 3: Total reaction cross sections for ¯ pp tion of plab , based on baryon-exchange (s the quark model (grid). Results obtained imation are indicated by the dotted (bary dash-dotted (quark model) lines, respective Q Q q q q q FIG. 4: Microscopic quark-model mechanism for the tion potential: annihilation of two pairs of light quark u¯ u, d ¯ d, and creation of a pair of heavier quarks, Q ¯ Q = (¯ cc) is created – see Fig. 4. We base our study model of Kohno and Weise (KW) [28] for the ¯ pp reaction; we replace parameters corresponding s−quark and K−meson of that model by those c−quark and D−meson. The quark-model ¯ NN transition potential V ¯ NN→D ¯ D Q (t) can be written V ¯ NN→D ¯ D Q (t) = χ† ¯ N [h1 (t) σ · p + h2 (t) σ · p] χN cutoff mass below. us now focus on the effects of the initial state inter- Those effects are included by solving the formal d-channel equations T ¯ NN, ¯ NN = V ¯ NN, ¯ NN + V ¯ NN, ¯ NN G ¯ NN T ¯ NN, ¯ NN , (4) T D ¯ D, ¯ NN = V D ¯ D, ¯ NN + V D ¯ D, ¯ NN G ¯ NN T ¯ NN, ¯ NN , (5) ng the ¯ NN potential described in Sect. II. rse, Eq. (5) implies that the ¯ NN → D ¯ D transition ude is effectively evaluated in a DWBA. ults with inclusion of ISI effects are presented as in Fig. 3 because we consider several variants of N potential as discussed in the previous section. bvious that the results change drastically once the ncluded in the calculation. The cross sections for are strongly reduced while at the same time those +D− are enhanced. Indeed now both D ¯ D channels oduced at a comparable rate. In fact, the predicted section for D+D− appears to be even somewhat than the one for D0 ¯ D0. ereas the reduction in the D0 ¯ D0 case is in line omparable effects observed in the previous stud- ¯ NN annihilation processes [23, 25–27], as men- above, the enhancement seen for D+D− may be 6.0 6.5 7.0 7.5 p lab (GeV/c) 10-3 10-2 6.0 6.5 7.0 7.5 p lab (GeV/c) 10-3 10-2 10-1 100 σ tot (µb) p FIG. 3: Total reaction cross sections for ¯ pp tion of plab , based on baryon-exchange (sh the quark model (grid). Results obtained imation are indicated by the dotted (baryo dash-dotted (quark model) lines, respectivel 82