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Precision Measurements, Small Cross-sections , and Non-Standard Signatures: Reaching the 1 fb -1 Threshold at the Tevatron. Henry Frisch University of Chicago. Looking for SUSY at the Tevatron… Data…. Electron+. CDF Event. 2 electrons and a photon: Ht=~350 GeV. Photon. 11/26/06.
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Precision Measurements, Small Cross-sections, and Non-Standard Signatures:Reaching the 1 fb-1 Threshold at the Tevatron Henry Frisch University of Chicago Looking for SUSY at the Tevatron… Data… Electron+ CDF Event 2 electrons and a photon: Ht=~350 GeV Photon 11/26/06 Electron- `Typical’ lepton+photon+X event (?) No Met- sorry….
Gordy as Pioneer “Have We Already Found Ourselves a Bearino In These Woods?” hep-ph/0701999
OUTLINE • Luminosity and Reach of the Tevatron and of Gordy* • The Triangle of Mtop, MW, and MHiggs • New Precision Measurement of MW • Precision Measurement of Mtop • Brief Summary of Higgs Results/Projections/Opportunities • Anomalous Top Production? • Anomalous Top Decay? • B ->m+m-, Bs mixing, other Precision tests • SUSY? –Met+jets • SUSY?- stop and H+ • Photon Signatures (lgX and ggX) and GMSB • Lepton Signatures Same-sign dileptons and trileptons • High-Pt Z’s, Right-handed Heavy Quarks,…,…. • Summary- the Tevatron Opportunity at >> 1 fb-1 • * A Man’s Reach …. – Robert Browning
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
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.)
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
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.)
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: Gordy Fest 1/19/07
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.
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
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!
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.)
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,…
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?)
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
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
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! ?
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)
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
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 !
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?
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
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…”
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…
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
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
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)
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).
High Precision B-physics; Mixing, Bs->mm Note: 1 psec = 300 microns. SVT is critical.
High Precision B-physics; Mixing, Bs->mm Pure Experimentalist’s reaction- pretty!
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).
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!
Gordy as Pioneer “Have We Already Found Ourselves a Bearino In These Woods?” hep-ph/0701999
Backup- D0 btagging Backup- lum on tape
Precision Measuremnt of the Top Mass TDR 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.)
Gordy as Pioneer “Have We Already Found Ourselves a Bearino In These Woods?” hep-ph/0701001