1. Charm and beauty production at the Tevatron Tara Shears University of Liverpool On behalf of the CDF and D0 collaborations 248, 725, 730

2. Tevatron p p collisions at s = 1.96 TeV CDFD0 _

3. Historical context: Run 1 Nason, Cacciari UPRF-2002-4 CDF Preliminary: (D*) Cacciari: hep-ph/9702389 (B+): Phys Rev D65 052005 B C Discrepancy from Run 1: B: (data)/ (improved theory) ~ 1.7 C: similar effects seen Aim: test predictions at Run 2

4. Tests of b and c production in Run 2 Inclusive b and c production: –Charm Phys. Rev. Lett. 91 241804 (2003) –Beauty Phys. Rev. D71 032001 (2005) –Combined c/b + X: –b + b –c,b + –b + Z Phys. Rev. Lett. 94 161801 (2005) –b +W Phys. Rev. Lett. 94 091802 (2005) _

5. 4 analyses presented: 1.Muon tagged jet production 2.Inclusive b production 3.bb production 4.Photon + heavy flavour production Tests of b and c production at Run 2 charm beauty Direct and combined measurements _

6. tagged jet production Require events with at least 1 jet, | | 5 GeV) Jet Et 90 – 400 GeV considered 294 pb -1 data analysed Extract heavy flavour component from simulation Measurement sensitive to b + c production Pythia MC

7. tagged jet production Results consistent with LO (Pythia CTEQ 6L) and NLO (NLOJET++ CTEQ6M) NLOJET++: Z. Nagy, Phys. Rev. Lett. 88 122003 (2002); Phys. Rev. D68 094002 (2003)

8. Inclusive b production Require 1 jet, | |<0.7, with separated secondary vertex Jet Et 38 – 400 GeV 300 pb -1 data analysed Determine b fraction by fit to secondary vertex mass Results compared to LO (no NLO yet) : ratio ~1.4 as expected

9. bb production Require 2 jets, | |<1.2, both with separated secondary vertex Et 1 > 30 GeV, Et 2 > 20 GeV 64.5 pb -1 data analysed Determine b fraction by fit to secondary vertex mass Calculate cross-section as fn. of : Jet Et, m(bb), (b jets) _ _

10. bb production Results consistent with LO (Pythia CTEQ5L) and NLO (MC@NLO + JIMMY U.E. simulation) Note: selection enhances flavour creation (LO) bb)(| | 30GeV, Et 2 >20GeV) = 34.5 ± 1.8 ± 10.5 nb LO: 38.7 ± 0.6 nb NLO: 35.7 ± 2.0 nb _

11. bb production Results consistent with LO (Pythia CTEQ5L) and NLO (MC@NLO + JIMMY U.E. simulation) _

12. + b / + c production Sec. Vertex mass (GeV) Et > 25 GeV (| |<1.0) + jet with secondary vertex Determine b, c, uds contributions (fit secondary vertex mass) Subtract bkg, find cross- section as fn. Et 25–29 GeV 29–34 GeV 34–42 GeV 42–60 GeV

13. + b / + c production Results consistent with LO ( +b) ( +c)

14. ( + c) / ( + b) Ratio consistent with LO

15. Charm, beauty production well understood theoretically at Tevatron in Run 2 –Many analyses published (inclusive b, inclusive c, W+bb, Z+b) Shown here: –Inclusive analysis in agreement with LO, NLO –Inclusive b ratio to LO as expected (NLO comparisons forthcoming) –bb production in agreement with LO, NLO – + b, + c in agreement with LO (4x stats. forthcoming) Conclusions _ _

16. Backup slides

17. b,c production @ Tevatron Gluon splitting Flavour excitation Flavour creation

18. How to isolate b,c experimentally Large cross-section Isolate by triggering on: –Decays to J/ –Semileptonic decays –Displaced tracks (SVT) s (TeV) 0.001 0.01 0.1 1.0 10 10 2 1mb 1 b 1nb 1pb SppS Tevatron LHC (ppX) (-) (bb)

19. Inclusive systematics QuantityUncertainty (%) Efficiency± 13.0 Luminosity± 6.5 Heavy flavour fraction± 20.0 Jet Correction ± 20.0 (P t =100) +80.0 -50.0 (P t =400) Unfolding ansatz± 5.0 Total ± 32.2 (100) +83.9 -56.0 (400)

20. Inclusive b systematics

21. Inclusive (bb) systematics QuantityUncertainty /nb Luminosity± 2.1 B tagging efficiency± 5.5 B fraction± 1.0 Acceptance (trigger efficency, jet corrections, pdfs) ± 7.0 Total± 10.5

22. + b / + c production Dominates for c Diagrams equal for b LO + (estimates from Madgraph)

23. Systematic errors: (b ) Systematic error (pb) 25 – 29 GeV 29 – 34 GeV 34 – 42 GeV 42 – 60 GeV Tag efficiency +1.7 –1.3+2.6 –2.0+0.9 –0.7+1.1 –0.9 Photon id ± 0.2± 0.1< 0.1± 0.1 Jet correction ± 0.5 ± 0.1 Jet energy scale +3.3 –1.4+2.2 –2.1+0.5 –0.3+0.5 –0.4 B jet correction ± 0.2± 0.3± 0.1 CPR fake estimate - 0.1< 0.1 trigger +2.5 –1.7< 0.1 PDF ± 0.3± 0.5± 0.2 luminosity +0.7 –0.6+1.1 –1.0+0.4 – 0.3+0.5 –0.4 Final value 11.2 +16.4 -8.2 17.2 +12.3 –10.1 6.2 +6.4 –4.4 7.9 +5.0 -4.1

24. Systematic errors: (c ) Systematic error (pb) 25 – 29 GeV 29 – 34 GeV 34 – 42 GeV 42 – 60 GeV Tag efficiency +26.5 –19.8+13.1 –9.9+7.4 – 5.6+8.7 –6.4 Photon id ± 2.2± 0.4± 0.3± 0.4 Jet correction +7.9 –7.2+2.5 –2.40.80.4 Jet energy scale +48.0 –21.0+10.4 –9.6+3.5 –2.4+2.9 –2.3 CPR fake estimate - 0.6- 0.1- 0.2+ 0.2 trigger +37.3 –25.3< 0.1 PDF ± 2.2± 0.7± 0.3± 0.2 luminosity +9.6 – 8.6+5.0 –4.4+2.8 –2.5+3.0 –2.7 Final value 164.7+163.2 -106.5 81.1 +71.0 –53.0 45.4 +46.8 –31.3 50.0 +37.3 –30.9

25. Systematic errors: (c )/ (b ) Systematic error (pb) 25 – 29 GeV 29 – 34 GeV 34 – 42 GeV 42 – 60 GeV B tag efficiency - 1.2- 0.6- 1.0- 0.8 C tag efficiency +2.4 –1.8+0.8 –0.6+1.3 –0.9+1.1 –0.8 B jet correction ± 0.2± 0.1 CPR fake estimate + 0.1< 0.1- 0.1< 0.1 Final value 14.1 +41.5 -9.8 4.8 +8.7 –3.3 7.4 +19.3 –5.4 6.4 +9.7 –4.1