Topics from the Topics from the Tevatron:Tevatron:

CDFCDF and and D0D0 at at 1.96 TeV1.96 TeV

And A Christmas And A Christmas Wish ListWish List

Henry Frisch

Enrico Fermi Institute and Physics Dept, University of

Chicago2004 Annual Theory Meeting, Durham, UK

Current Status of the Tevatron Complex, CDF and D0

Pbar-p Luminosity vsYear per expt.

Note `goals’ are `Delivered; data points are ‘Published’.

Recycler (2000-2004) is 8 GeV machine in Main Injector (1999) (foreground) – where electron cooling is now being installed. 7 accelerators used in pbarp.

Note Chicago !

CDF SVX/ISL remains as is: good for > 4 fb-1 ?

D0 Si is less radhard; add new Layer 0 for

Run IIb

Run 2b silicon detector upgrades--critical for top, Higgs, b-physics, …

(most everything)

Inclusive Jet Spectrum- excess

at high Pt or PDF’s (or scale error)?

Note reach: kinematic limit is 980

IWish List Item: Answer to Q: Can one calibrate highest Et jets against sum of several lower Et jets? E.g. take events with only 1 jet in hemisphere and max jet in opp. hemisphere < 60% of 1st jet; balance sums in 2 hemispheres (i.e. a bootstrap calibration.)

High Et jets- comparison to expectations

Wish List Item: comparable plots from both experiments (!).

Measuring Jets

Wish List Item: Answer to Q: What are the theoretical limitations on the ratio of gamma-b(c)/gamma-jet balancing?

Un-Ki Yang, Adam Gibson

Jet energy scale is critical to top mass measurement

B-jets contribute most to mass (don’t have W mass constraint)…

Promising Idea:

Balance photon and b-jets to calibrate response

The Top Mass and the W Mass :

Two key precision measurements: calib.!

Error on W mass has scaled inversely with sqrt of luminosity so far – now at 59 MeV. what are our expectations with 10-20X more data?

Modelling requires NLO QCD and QED in same MC

Underlying event is 30 MeV/interaction in CDF- need to get from data

Recoil event modelling depends on W Pt at low Pt- also need to get response from data

Modelling requires NLO QCD and QED in same MC

Recoil event modelling depends on W Pt at low Pt

Underlying event (uev) is 30 MeV/tower/interaction in CDF- indicates scale of precision needed- must get all detector response to uev from data (i.e. not MC).

Old idea (UA2, CDF Run 1a)- use Z sample to get detector response to recoil. E.g. (D. Saltzberg) for each W from MC use measured recoil from a Z with the same Pt. Limiting factor for using Z’s was factor of 10 smaller X BR.

W Mass Measurement Limited by Theoretical Issues?

Q: Will future require measuring W and Z mass simultaneously by same technique? If so, need QCD/QED NLO, Z/int.., for Z.

A. Focus on W and Z production and higher order differences

Run 2 detectors still commissioning - not caught up to Run 1 despite more and better data.

More sophisticated techniques- D0 DLM Run 1 reanalysis: 173.3 +/- 7.8 goes to 180.1 +/-5.3 GeV

Top Quark Mass Measurements

Advice- take 1-sigma on Mtop seriously!

Sensitivity of EWK fits to top mass

This change is due to the D0 remeasurement of the same data, same calibrations, different sample weighting- Xmass Wish list item: detailed explanation of what caused the shift in mtop- same events.

SM Higgs

Reworked Sensitivity Estimates (2003)

Run 1- 100 pb-1, 1.8 TeV, 1 expt.-

Eyeball estimator: scale this by expected luminosity in Run II

Standard Model HiggsCDF+D0 initial Run 2

results

Z- Interference

Run 1 CDF two highest mass events were `backwards’- sensitive to higher-mass Z’s through interference.

Lovely gamma-Z interference for QM class…

Above the Poles:

The W Width Direct Measurement

Insensitive to radiative corrections- good place to look for new Jacobian peaks- see Rosner, Worah, and Takeuchi, PRD49,1363 (1994) (hep-ph/9309307)

Idea (HF, Sacha Kopp, J. Rosner)- Breit-Wigner should fall slower than resolution (power law vs Gaussian, hopefully)…

From D0- MC

Above the Poles: The W Width Direct Measurement

W = 2.011+/- 0.142

World Average and SM Prediction

Systematics are largely from the Z, hence statistics-limited: note Z/W is 1.25 at pt=100, 1.5 at pt=200 (Arnold and Reno, Nucl Phys B319, 37, 1989)

W Asymmetry

W Asymmetry

CTEQ6 comparison with uncertainties

vs , PT, (mass) e/Z

e Wo

Wish List Item: Answer to Q: is the ratio

sensitive to PDF’s in a different way?

High Pt Photons as New Physics Signature: (e.g. CDF Run1 eeevents)

Are Run 1 anomalies real? Experiments see only upward fluctuations- can estimate factor of luminosity needed to get

to the mean (though huge uncert.)

High Pt Photons as New Physics Signature: `W-gamma’ (l-met-gamma):

Exact Repeat of CDF Run 1 cuts in progress (Andrei Loginov)

hmm

High Pt Photons as New Physics Signature:

`Zgamma’ (ee or mumu-gamma):

(superset of CDF eeevents

Need more luminosity- keep an eye on…

Diphoton + Missing Et (met)

Again signature includes dilepton-diphoton, one lepton-diphoton…

`Top’ Dileptons- 2 e or mu, met, jets

`Top’ Dileptons- 2 e or mu, met, jets

`Top’ Dileptons- 2 e or mu, met, jets

Also to watch- by eye LH looks like CDF Run 1 at large met?

One of Hardest Problems is precise predictions of W,Z+Njets

Each with at least on tag in this case- this from top crossection meas.

One of Hardest Problems is precise predictions of W,Z+Njets

L. Beitler from datasets with CKKW matching made by Steve Mrenna– see S. Mrenna and P. Richardson, hep-ph/0312274

One of Hardest Problems is precise predictions of W,Z+Njets

Each with at least on tag in this case- this from top crossection meas.

•With luck (truly) we have a shot at exploring LOTS of channels, topics, opportunities

•a large region of unexplored kinematic and signature space.

•Big effort now on machine performance

•Detectors working well enough- detailed calibrations still in progress

Conclusions and Wish List

Wish List•Peace on Earth•Long life to the machine, CDF and D0, and a low scale for rich new physics --`all the above’-i.e. SUSY, ED, E(6),…..

Acknowledgements-

Thanks to all the Beams Division, and the CDF and D0 physicists and staff. Thanks also to all the technical folks at other institutions and also those at Fermilab who make this all possible. Merry Xmas to all!

The End