1. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20031 Blessing of Run II Diffractive Results Introduction Data Selection Plots for Blessing

2. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20032 Forward Physics Hard Single Diffraction Double Pomeron Exchange …

3. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20033 Diffractive Dijets Compare diffractive events to ND Measure diffractive structure function from R SD/ND vs x bj Measure  pbar momentum loss fraction) from calorimeter information

4. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20034  Momentum Loss Fraction Diffractive events are boosted towards positive   small  Measure fractional momentum loss of anti-proton M X 2  s   =  y  ln (1/     e  ss

5. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20035 Trigger RP is triggered on leading antiprotons Use RP + jet triggers require jets

6. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20036 Data Sample Use dedicated diffractive triggers  RP+J5 (diffractive sample)  J5 (control sample) Data sample ~9 pb -1 (PHYSICS_1_03_v1)

7. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20037 Event Selection 1.Triggered events352,359 2.MET Significance<6352,359 3.Two jets (E T >5, |  <2.5)175,292 4.RP coincidence 168,153 5.SD (0.02<  <0.1) 15,209 6.All BSC East Gap 1,126

8. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20038 Question #4 Q : What is the ratio SD/ND for E T > 10 GeV ?

9. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 20039 DSF with Jet E T cut E T * = E T 1 + E T 2 2

10. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200310 Q 2 Dependence

11. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200311 Answer to Q#4 A : Slope and normalization change by ~ 1%. Q : What is the ratio SD/ND for E T > 10 GeV ?

12. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200312 Plots For Blessing Suggested modifications have been implemented

13. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200313  Distribution

14. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200314 Rapidity Run I PRL  Diffractive dijets are boosted away from the recoil antiproton

15. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200315 Mean Dijet E T

16. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200316  jet 1 -jet 2 )  Diffractive dijets are more back to back

17. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200317 MP Multiplicity

18. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200318 Diffractive Structure Function

19. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200319 Diffractive Structure Function (II)

20. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200320 East Multiplicity: BSC vs MP

21. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200321 DPE Enhanced Sample Study a dedicated DPE trigger (RP+J5+GapE) ~300 k events E T (jet 1,2 )>5 GeV |  (jet 1,2(,3) )|< 2.5 (0,0) bin  ~ 16,000 events (in Run I: 100 evts)

22. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200322  jet 1 -jet 2 )

23. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200323 Dijet Mean Rapidity

24. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200324 Jet Transverse Energy

25. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200325 Conclusions Relax, it is only physics.

26. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200326 Question # 1 Q : Is the BG peak at  ~ 1 due to overlap events from multiple interactions?

27. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200327  Distribution

28. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200328 Luminosity Dependence Luminosity:1.0 E31 1.5 E312.3 E31

29. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200329 Overlap Rate  ND (1 - e - n RP ) +  SD (1 - e - n )  SD e - n R (ND/SD) = J5 x RP overlap SD x MB overlap n RP = ( 1 mb/50 mb) x n, n = 0.3 x L[1 x E31]  ND /  SD ~ 600  R (ND/SD) = 12 n e n SD surviving MB overlap

30. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200330 Multiple Interactions Shift ND Peak R vs log (1 + n )

31. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200331 Run I vs Run II Run I Run II L um / bunch 0.16E30 / 6 20.0E30 / 36  ND /  SD 300 (lower jet E T ) 600 R (Run I/Run II ) = 1/60 R (Run II) = 10  R (Run I) = 0.15

32. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200332 Multiple Interactions

33. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200333 Answer to Q# 1 A : Yes. 1.Ratio is consistent with Run I numbers and Run II expectations. 2.Peak at  ~ 1 shifts according to luminosity, as expected. Q : Is the BG peak at  ~ 1 due to overlap events from multiple interactions?

34. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200334 Question #2 Q : What is the effect of the MP energy scale calibration ?

35. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200335 MP Calibration Use slope from ADC distribution Tower-to-tower relative calibration with data/MC Energy scale from MC MC/MBR Pile-up at high luminosity (Slope-Fit)/Fit ~7% for each  ring Time dependence (LED)

36. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200336 MP Multiplicity

37. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200337 MP Contribution to  ND

38. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200338 Effect of MP Energy Scale  E = +/- 25%    log  = +/- 0.1

39. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200339 Answer to Q#2 A : An energy scale variation of +/- 25% yields  log  = +/- 0.1.  log  =0.1 is the bin width of our  distribution. 2.Peak position in data is centered where expected, indicating the energy scale uncertainty is < 25%. Q : What is the effect of the MP energy scale calibration ?

40. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200340 Question #3 Q : What is the background in the RP inclusive rate ?

41. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200341 RP Inclusive Data

42. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200342 Zero Crossings

43. M. Gallinaro, `` RunII Diffractive Results: Blessing'' - QCD meeting, March 7, 200343 Answer to Q#3 Q : What is the background in the RP inclusive rate ? A : It is 1-2% of all RP triggers, concentrated at log  < - 3