XLII Rencontres de Moriond QCD and High Energy Hadronic Interactions March 2007

XLII Rencontres de MoriondQCD and High Energy Hadronic Interactions

March 2007

Experimental Summary

Gigi RolandiCERN PH

[email protected]

Moriond QCD 2007Experimental Summary

2Gigi Rolandi / CERN PH

Colliders&Colliders

Logged 710 fb-1

Logged 410 fb-1

TEVATRON

BABAR@PEP-IIBELLE@KEKb

HERA

CLEO@CESR

BES@BEPC

KLOE@DAPHNE

RHIC

SPS



Many many beautiful talks !



• …… Impossible to make a “summary” ( less than 1 min/talk !)

• Choice of the topics based on my ignorance and my taste

•Personal bias

•Electroweak

•Higgs and single top

•Unitarity triangle

•D0-D0bar Mixing

•Extras

•No names will be mentioned …. Only Collaborations



Angular Correlation of charm pairs

B0 7000 Signal events S/B 8.3 at the peak

BsK+-

CDF SVT Trigger

Bs Direct CP Asymmetry



CLEO

M(D0) reduced 0.2*PDG

Q=340MeV

Measure yelds of double tag and single tag events . BRs extracted in a global 2 fit.

26 M (2s)

c0 --> KK



Diffraction and pQDC@NLO

Large gluon content

Diffractive PDFs are not universal Factorization broken at Tevatron

x=xip*



DIS is well described by pQCD@NLO

+ jet

CDF

Dijet

(ep--> D*X)

ep-->bbX

ep-->ccX

Dijet b-bbar

e(±)p scattering



Gluon content of the proton

Are the PDFs usable in the LHC kinematic range (1 > x > 10-6) ?

Higher-order terms are important at low Q2, low x

Will LHC see saturation at very forward rapidities : x ~ 10-6 ?



Heavy Ions @ RHICPseudo Rapidity dependence

Elli

ptic

flo

w

STAR, Phys Rev Lett 91, 072304

Jet quenching in Central Collisions



Precise Measurements of W mass and Top

Which top mass are we measuring ?



Electroweak Fit

• Preferred value: mH = 76 GeV at minimum

• Upper limit: mH < 144 GeV

NEW! March 2007, LEP EW WG



Evolution of EW FIT

Evolution on MH from EW Fit

0

50

100

150

200

250

300

2000 2001 2002 2003 2004 2005 2006 2007 2008

Year

MH (GeV)

MH Central valueMH 95% upper limit

Evolution on MH from EW Fit

0

50

100

150

200

250

300

2000 2001 2002 2003 2004 2005 2006 2007 2008

Year

MH (GeV)

MH Central valueMH 95% upper limit



Evolution of Mtop and MWEvolution of Mtop and Dmtop

0.00%0.50%1.00%1.50%2.00%2.50%3.00%3.50%4.00%4.50%

2000 2002 2004 2006 2008Year

Mtop/170.9-1

DMtop/Mtop

Evolution of MW and DMW

-0.02%-0.01%0.00%0.01%0.02%0.03%0.04%0.05%0.06%0.07%0.08%

2000 2002 2004 2006 2008Year

MW/80.398 -1

DMW/80.398



Mw-Mtop and MSSM

George Weiglein



SM Higgs Production X-section TeV/LHC

SM Higgs Production at LHC

Te

vatr

on



Channels in Higgs Search

Very small rate : concentrate on channels with high Higgs Br

TevatronATLAS CMS

Large Rate: signals with smaller BR

Atlas : qqH--> qqWW, qq

Atlas: H-->ZZ,WW,

CMS: H--> , ZZ, WW

CMS: qqH--> qq,qq

Significance 30 fb-1



Number of Events in 1 fb-1

Produced Selected BackgroundZH-->llbb 5 1 100ZH--> ννbb 15 2 300

-->WH l νbb 30 3 500--> -->H WW ll νν 20 4 300

Tevatron

LHC

Produced Selected BackgroundH(135)--> 86 30 300 CMS

(140)--> *-->H ZZ llll 13 3 500 CMS

(160)--> -->H WW llnn 2300 45 30 CMS

(160)--> -->qqH qqWW qqllnn 280 4 1 ATLASCMS



SM Higgs at the Tevatron

not included in the plot

How To Extrapolate to 8 fb-1 ? Watch at the excess



First Evidence of Single Top

D0Bayesian NN Matrix Element Decision Trees

Exp. Obs. Exp. Obs. Exp. Obs.

(tb+tqb)[pb] 3.2 +2.0-1.8 5.0 ± 1.9 3.0 +1.8

-1.5 4.6 +1.8-1.5 2.7 +1.6

-1.4 4.9 ± 1.4

Significanc 1.3 2.4 1.8 2.9 2.1 3.4

CDFMatrix Element Neural Network Likelihood ratio

2.3 excess No evidence. No evidence.

(tb+tqb)[pb] 2.7 +1.5 -1.3 < 2.6 < 2.7

….seen by D0. CDF has no evidence.

Situation pretty complex but not unusual for first evidence.

(D0) = 1.5+/- 0.4 (SM) also this not unusual

Preliminary



Single Top and Higgs Search

D0 Single Top

CDF ZZ--> llνν

In 1 fb-1

Produced Selected Backgroundt--> Wb-->l ν b 650 36 600

--> ( +ZZ ll ll νν) 20 9 23

Produced Selected BackgroundZH-->llbb 5 1 100ZH--> ννbb 15 2 300

-->WH l νbb 30 3 500--> -->H WW ll νν 20 4 300



Higgs in MSSM

Amplitude is ~tan, hence the cross section is enhanced as tan2CDF search in h-->ejet D0 see a deficit in the same mass region

CDF search in double leptonic channel not conclusive



Exclusive di-jet x-section at Tevatron

Calibrate scale of predictions

Relevant for pp-->ppH



Diffractive Higgs @ LHC

The diffractive production of the Higgs pp-->pHp opens the possibility to measure its quantum numbers and its mass with high precision exploiting the measurement of the outgoing protons momenta in the roman pots.

100 fb-1

• X-sections O(1fb) --> Large Luminosities

• Pile up in coincidence with di-jet production is an overwhelming source of background

•To resolve different interactions in the same bunch crossing one needs a time coincidence between the two protons at the level of 3mm i.e. 10 ps



B

+other charmonium

radiative decays Xs,Xd, Xsll

B DK

+from Penguins

Charm Physics(Dalitz)

?

theo. clean

HF Physics:Unitarity Triangle



New Measurements of sin2

d d

sb

W

B0d

t s

s

K0

g

sb b s

~

~ ~

New Physics contribution (2-3 families)

( )LRd

23δ

b

d

c

csd

J/

K0

B0d



Precise Measurement of ms

After LEP and D0…..

With Neural Net Selection and same side tagging

md --> 1% - ms --> 0.7% - 68



Progress on Vub

Inclusive : stability in extrapolation to full phase space

B Xu l ν B l ν

Exclusive :measurement of form factors



IS THIS CONSISTENT ?

sin2 =0.76± 0.04from indirect determination

(all included but sin2)



sin2=0.68±0.03From direct measurement

b--> ccs


b--> ccs


Naïve averageb--> qqs



ms



IS THIS CONSISTENT ?






b--> ccs


b--> ccs





Robust: Dominated by Vub, SM tree level, non dependent on NP

Experimentally robust, but measures 2(SM+NP)

Naïve average of measurement affected by penguins in a different way….



Mixing in D0 -D0bar system Observed

BaBar

DCS decays

Interference “Oscillations”

ΓΓ

=Γ

=2

, ym

xδδ cossin' yxy +−=

δδ sincos' yxx += Strong phase

No mixing 2=24 -

Mixing+resolution from likelihood fit 2=1.5

3.9

3' (9.7 4.4 3.1) 10y −= ± ± ×'2 3( 0.22 0.30 0.20) 10x −= − ± ± ×



Evidence for D0 -D0bar Mixing

Belle

Time dependent analysis of Dalitz plot

Lifetime difference



D0 -D0bar Mixing: Comparison

δδ cossin' yxy +−=

δδ sincos' yxx +=

Belle 2 statistical

BaBar 2BaBar 3

BaBar 1

(0,0)

stat. only

y’ /10-2

x’2/10-2

Ciuchini et al hep-ph/0703204

δ=-38o±46o



Is Bayesian approach biasing ?

AristotelePlatone



Is Bayesian approach biasing ?

Bayesian Frequentist

My cent: use frequentist approach if you can. It is correct. In many cases it is not-practical…. Then use Bayesian approach and common sense . And show the relevance of the assumptions on the Prior Probability.

hep-ph/0701204 hep-ph/0607246



Conclusions

• Very large samples of data are available allowing precise measurements and studies of rare phenomena

•I have been impressed by the quality (and the complexity) of the analyses that have been presented

•The steady progress in the field is marked by discoveries of new expected phenomena that have been recently seen: DDbar mixing, Single top, ZZ

•QCD is - generally speaking - in good shape and describes well the hadron production at high and low Q2

•This accurate description requires a monumental effort both on theory and experimentation and is needed for the searches of new physics at hadron colliders and at lower energy

•Everybody is waiting for the start of LHC. It is close. At Moriond XLIV we will see the first presentations with data, but it will take time to understand the detectors

•In the mean time watch the Tevatron, the Triangle and the rest…. The devil is in the details of experiments and theory



Thanks

• To Tran for the 42 Moriond that he invented for us

• To the organizers for a well organized conference

• To all the speakers for their very good talks

XLII Rencontres de Moriond QCD and High Energy Hadronic Interactions March 2007

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