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Precision Measurements, Small Cross-sections, and Non-Standard Signatures: The Learning Curve at a Hadron Collider ( t

Precision Measurements, Small Cross-sections, and Non-Standard Signatures: The Learning Curve at a Hadron Collider ( t L ). Henry Frisch University of Chicago. `EM Objects’: E/p < 2: Electron E/p> 2: Jet P <1: Photon. Electron-. Recent event emailed by CDF detector, e.g.

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Precision Measurements, Small Cross-sections, and Non-Standard Signatures: The Learning Curve at a Hadron Collider ( t

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  1. Precision Measurements, Small Cross-sections, and Non-Standard Signatures:The Learning Curve at a Hadron Collider (tL) Henry Frisch University of Chicago `EM Objects’: E/p < 2: Electron E/p> 2: Jet P <1: Photon Electron- Recent event emailed by CDF detector, e.g. Where p is from track, E is from cal E/p measures bremstrahlung fraction Electron+ Photon Some recent results, and some thoughts on the future ( “It’s hard to predict, especially the future”- Niels Bohr)

  2. Acknowledgements • Thanks to many CDF and D0 colleagues whose work I’ll show… Also SM MC generator folks! • Apologies to D0- I tend to show much more CDF than D0 as I know it much better • Opinions and some of the plots are my own, and do not represent any official anything.

  3. Tevatron experience indicates: It will not be luminosity-doubling time but systematics-halving time that determines when one will know that one no longer needs the Tevatron. We should NOT shut off the Tevatron until we have relatively mature physics results from the LHC (i.e. it’s clear that we won’t need the different systematics.) Have lots of hadron-collider experience now- 1. remarkable precision in energy scale possible (MW); 2. remarkable precision in real-time reconstruction and triggering (e.g. SVT triggering on B’s at CDF); 3. remarkably long and hard development of tools (e.g. jet resolution, fake rates, tau id, charm, strange id).

  4. OUTLINE • Weisskopf Panel’s 3 Frontiers (1974 Woods Hole) • Luminosity and Reach of the Tevatron • Quick intro/status to areas of opportunity: • A. Precision Mass Measurements: The Triangle of Mtop, MW, and MHiggs • B. Brief Summary of Progress on the Higgs Reach • C. Photon Signatures: (lgX and ggX) and GMSB • D. Lepton Signatures: Same-sign dileptons; trileptons • E. Bs ->m+m-, Bs mixing, other Precision tests • 4. Areas complementary to LHC strengths • 5. Still to be learned at the Tevatron (20 yrs later) • 6. The attraction of hardware upgrades, and the ILC • Summary- the Tevatron Opportunity at 1.5-2 fb-1 /year

  5. Weisskopf 1974 Woods Hole Panel • Three frontiers: • 1. Energy Frontier (now LHC, Auger, Anita) • 2. e+e- (to be ILC) • 3. Precision tests (EWK, flavor, FCNC,… - could (should) be a role for the Tevatron at least until LHC is well-understood.

  6. Luminosity vs Time Run II CDF Run II So Far Run II Run II Delivered Lum D0 (CDF+D0)/2* Note pattern- integral grows when you don’t stop, with increasing slope *(Protons are smaller on this side (joke)) > 40 pb-1/wk/expt

  7. Peak Lum coming up on 3E32 40-50 pb-1/wk times 40 weeks/yr = 2 fb-1/year delivered per expt- There are more pbars even now. Peak lum problem =>Luminosity leveling?

  8. Where is the Higgs? Mtop vs MW 1s Assuming SM (H->bb) Note log scale Central Value Tev/LEP2 Mtop vs MW Status as of Summer 2006 (update below) Central value prefers a light (too light) Higgs Puts a High Premium on Measuring Mtop and MW precisely, no matter what happens at the LHC (really diff. systematics at Tevatron.)

  9. The Learning Curve at a Hadron Collider (tL) Take a systematics-dominated measurement: e.g. the W mass. Dec 1994 (12 yrs ago)- `Here Be Dragons’ Slide: remarkable how precise one can do at the Tevatron (MW,Mtop, Bs mixing, …)- but has taken a long time- like any other precision measurements requires a learning process of techniques, details, detector upgrades…. Theorists too(SM) Electron+ Electron-

  10. Precision Msremnt* of the Top Mass CDF Lepton+4jets: Jet Energy Scale (JES) Set by MW (jj) Note FSR, ISR, JES, and b/j JES dominate- all measurable with more data, at some level… 4 2 1 3 Systematics: This is very good news! *like Mrenna

  11. Precision Measuremnt of the Top Mass TDR • Aspen Conference Annual Values • (Doug Glenzinski Summary Talk) • Jan-05: Mt = +/- 4.3 GeV • Jan-06: Mt = +/- 2.9 GeV • Jan-07: Mt = +/- 2.1 GeV Note we are doing almost 1/root-L even now Setting JES with MW puts us significantly ahead of the projection based on Run I in the Technical Design Report (TDR). Systematics are measurable with more data (at some level- but W and Z are bright standard candles.)

  12. Higgs Limits have gone faster than 1/root-L; faster than 1/L

  13. One old feature may be going away-top mass in dileptons was too low… Mtop(All Jets) = 173.4 ± 4.3 GeV/c2 Mtop(Dilepton) = 167.0 ± 4.3 GeV/c2 Mtop(Lepton+Jets) = 171.3 ± 2.2 GeV/c2 ( Rainer Wallny, Aspen 07) Dilepton a little low, but statistically not significant- also D0 number not low now… Take differences between the 3 modes:

  14. New (Jan. 5, 07) CDF W Mass From Ashutosh Kotwal’s Jan 5 Wine and Cheese (Fermilab) Data from Feb. 02-Sept 03 218 pb-1 for e; 191 pb-1 for m A Systematics Intensive Measurement.. This is a precision spectrometer! Note: This is a small fraction of data taken to date- this is to establish the calibrations and techniques (so far) for Run II.

  15. New (Jan. 5, 07) CDF W Mass From Ashutosh Kotwal’s Jan 5 Wine and Cheese (Fermilab) Run Ib Problem Now Solved: 2 Calibrations of EM calorimeter: Zmass ≠ E(cal)/p(track) Electron and Muon Transverse Mass Fits

  16. New (Jan. 5, 07) CDF W Mass From Ashutosh Kotwal’s Jan 5 Wine and Cheese (Fermilab) Note: This is with only 0.2 fb-1 and one experiment!

  17. MW-Mtop Plane with new CDF #’s MW= 80.398 \pm 0.025 GeV (inc. new CDF 200pb-1) MTop = 171.4 \pm 2.1 GeV (ICHEP 06) => MH =80+36-26 GeV; MH<153 GeV (95% C.L.) MH < 189 GeV w. LEPII limit (M. Grunewald, Pvt.Comm.)

  18. Direct Limits on SM Higgs This is the factor one needs to get the 95% CL downto the SM Higgs Xscn D0 has updated high mass region CDF has updated low mass region I’m not willing to prognosticate (other than to bet we don’t see the SM Higgs)- would rather postnosticate. However, lots of tools not yet used- we’re learning many techniques, channels,…

  19. New CDF Higgs result: Tau ID depends on good tracking, photon ID- clean environment (all good at the Tevatron). Key numbers are efficiency and jet rejection: J. Conway- Aspen

  20. New CDF Higgs result: J. Conway- Aspen

  21. New CDF Higgs result: Need More Data- keep on running. Other channels too… Have more handles- e.g. tau displaced vertex.. J. Conway- Aspen

  22. New Physics inTop Production? Note 1 TeV Note no 500 GeV bump anymore Fit ttbar system with known top mass(es) and compare Mtt, pTtt,etatt,X, angular distributions, etc. with SM expectations. Global fit allows multi-dimensional comparisons. (Here is only Mtt, for reasons I don’t understand- Dan?)

  23. New Physics inTop Decay? 750 pb-1 Dilepton only 200 pb-1 ? So far no smoking guns • Fit for V-A, V+A, longitudinal: • Charged Higgs (e,mu+tau+b) • Run I odd dilepton distributions 750 pb-1 V+A fits, e.g

  24. Single Top Production Yann Coadou, Aspen 07 CDF ME D0 SM CDF NN CDF LK Zack Sullivan, Aspen 07 Situation somewhat confused- Expect 1 and 2 pb in s and t channels, respectively. Need more data, wits

  25. SUSY? - Same-sign dileptons and trileptons CDF: SS: 2 of e and/or m: Pt1>20,Pt2> 10; Met > 15 Counting expt agrees, but some extra high Pt SS events on tails. More data! ?

  26. SUSY? - trileptons Many CDF analyses combined: Note- in ~1000 pb-1 have only a few events. But limits are in the 1 pb-1 range… DATA and SM! (fergit specific models) Note: In model interpretations limit is very parameter dependent, and for LH plot there isn’t a limit on chargino mass. No Slepton mixing (D0 case)

  27. SUSY? – Missing Et + Jets Zone A: Met > 75, Ht > 230, Jets > 95, 55, 25 Zone B: Met > 90, Ht > 280, Jets > 120, 70, 25 Zone C: Met > 120, Ht > 330, Jets > 140, 100, 25 CDF: 371 pb-1 (1 fb-1in progress) SM Bkgd Makeup: Zone B Note how few events are out here from anything Data: Zone B HT (sum ET) spectrum RESULTS: DATA VS SM EXPECTATIONS

  28. SUSY? – Missing Et + Jetsnew (Jan. 5,07) D0 measurement Cut Cut D0: 1 fb-1 Gluino 3-jets 3 (Sub-) Analyses: all with 2j > 35, met> 75 GeV, lepton veto; Df12 < 165o + dphi(met-jet) cuts Thanks to D0 for help with this !

  29. SUSY? – Missing Et + Jets Yellow is uncertainty from PDF’s, Q2 scales in quadrature (?) Brown is D0 310 pb-1 New Combined (but useless to all but MSUGRA experts) Exclusion MSUGRA Plot: m<0; A0=0 CDF: 371 invpb Tan beta=5 D0: ~1000 invpb Tan beta =3 (gr-red line is mean limit (?)) What would it take to get both D0 and CDF to agree on some common points, e.g. same tan beta?

  30. eeggmet Event Followup and Signature-Based Searches Rather than look for a specific model, test the SM predictions in inclusive but interesting channels- gauge bosons+X, 3rd generation +X

  31. Signature-based Searches – eeggmet Event Followup (lg+X,gg+X) One event from CDF in Run I fot me (and Gordy, remarkably enough) excited- 2 high-Pt electrons, 2 high-Pt photons, large missing Et, and nothing else. Lovely clean signature- and very hard to do in the SM (WWgg). 2 Run I analyses looked for `cousins’ in 86 pb-1 - spread a wide net: 2 photons+X (X=anything; Toback) and photon+lepton+X (Berryhill). In g-l+X found a 2.7s excess over SM. From PRL: ``CDF Run I PRL: ..an interesting result, but … not a compelling observation of new physics. We look forward to more data…”

  32. SUSY? – eeggmet Event Followup Andrei Loginov repeated the lgmet analysis- same cuts (no optimization- kept it truly a priori. Run II: 929 pb-1 at 1.96 TeV vs Run I: 86 pb-1 at 1.8 TeV Conclude that eeggmet event, l+g+met `excess’, Run II Wgg event all were Nature playing with us- a posteriori searches show nothing with more data…

  33. Signature-based Searches – eeggmet Event Followup 929 pb-1 929 pb-1 Distributions look good too- small numbers of events on tail, but QCD bkgds there too. Sad- but led to systematic search strategies- and emphasis on SM prediction faithfulness- and not over yet. (Andrei Loginov PhD Thesis, ITEP, Moscow

  34. Signature-Based High Pt Z+X Searches Look at a central Z +X, for Pt > 0, 60, 120 GeV, and at distributions… (idea being new heavy things- e.g. QR a la Bj, Rosner, and/or Carlos…) Sasha Paramonov, UC

  35. Signature-Based High Pt Z+X Searches PTZ> 60 PTZ>0 PTZ> 60 PTZ>0 PTZ>120 PTZ>120 HT for PTZ>0, PTZ> 60, and PTZ>120 GeV Z’s: ee (Left) and mm (right)

  36. Signature-Based High Pt Z+X Searches PTZ>0 PTZ>60 PTZ> 60 PTZ>120 Njets for PTZ>0, PTZ> 60, and PTZ>120 GeV Z’s vs Pythia (Tune AW)- this is the control for Met+Jets at the LHC (excise leptons – replace with neutrinos).

  37. High Precision B-physics; Mixing, Bs->mm Note: 1 psec = 300 microns. SVT is critical.

  38. High Precision B-physics; Mixing, Bs->mm Pure Experimentalist’s reaction- pretty!

  39. High Precision B-physics; Bs->mm Copious Source of B’s; Mass Resolution and Trigger Result: World's best limits BR( Bs → μμ ) < 1.0x10-7 @95% CL BR( Bd → μμ ) < 3.0x10-8 @95% CL BR( Bs → μμ ) < 8.0x10-8 @90% CL BR( Bd → μμ ) < 2.3x10-8 @90% CL This is with 780 pb-1; have more, and have improved analysis sensitivity- new # very soon. Getting to have teeth (imagine 10X data+>Accept.). One of a number of rare-decay mode searches;Bs->mmX; also new states with B quarks, …. (whole industry).

  40. Conclusion (but not yet an ending) • Tevatron running well and producing lots of beautiful rich data • Experiments running pretty well and producing lots of hands-on and minds-on opportunities (lots of room for new ideas, analyses, and hardware upgrades (great for students!) • Precision measurements- MW, Mtop, Bs Mixing, B states- MW and Mtop systematics statisics-limited • Can make a strong argument thatpbar-p at 2 TeV tis the best place to look for light SUSY, light Higgs,…; as met at EWK scale, (MW/2, Mtop/4) doesn’t scale with mass, root-s, and tau’s (maybe b’s) are better due to lower mass in detector, and SVT and L1 tracking triggers, • All of which implies keep the Tevatron running until we know that we don’t need it. • Gordy has played a big role in the thinking of the whole field- Happy Birthday Gordy!

  41. Backup- D0 btagging Backup- lum on tape

  42. Luminosity vs Time Run II CDF Run II So Far Run II Run II Delivered Lum D0 (CDF+D0)/2* Xmas week Note pattern- integral grows when you don’t stop, with increasing slope *(Protons are smaller on this side (joke)) > 40 pb-1/wk/expt

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