Summary of the

Heavy Flavour Session

Joined HFL+PDF Session

Katerina Lipka (DESY)

Deep Inelastic Scattering 2010 Florence

Heavy Flavour Session

• HQ and QCD tests: H1 + ZEUS + CDF

• charmonium in ep and pp

• open charm and beauty in ep

• HQ and nucleon structure: H1+ZEUS, NOMAD

• charm and beauty structure functions

• Joined Session PDF+HF: HQ in PDF fits

• SM tests via HQ in e+e- : BaBar+ Belle

• HQ in heavy ion collisions and pp: STAR, PHENIX

• Top Quark: CDF, D0

• Cross section, mass, other properties

• First steps at the LHC: ALICE, ATLAS, CMS, LHCb

WG IV Summary 3

Charmonium: Inelastic J/ production in epTalks: M. Steder, A. Bertolin

Test QCD: Color Singlet vs Color Octet:

Cross section measurement vs pT(J/) and z=E/E

CSM NLO:

describes shape, not normalization

NRQCD (CO):

Recovers normalization

Fails to describe shape of elasticity z

s=320 GeV

WG IV Summary 4

Charmonium: J/ Polarization in epTalks: M. Steder, A. Bertolin

Additional test of the production models

Polarization parameters extracted using angular measurements

Goal: look for evidence of CO terms at HERA

Various predictions show different deficits to describe the data

Final conclusion needs higher order calculations

WG IV Summary 5

Upsilon polarization in ppT.Kuhr

transverse

longitudinal

Trend to longitudinal polarization observed

CDF disagrees with D0

Data disagree with NRQCD

J/ polarization not described by NRQCD! mc too low?

NRQCD

WG IV Summary 6

Open charm, beauty at HERAZ. Staykova, V. Aushev, M. Lysovy, P. Thompson, M. Brinkmann, P. Roloff

• c, b (+ jets) in DIS and p: powerful test of pQCD

• Structure functions F2c, F2

b : direct test of g(x)

c-, b- tagging methods:

reconstruction of charmed mesons, vertex information

different methods have orthogonal uncertainties

Factorization: (HQ) = proton structure hard ME

WG IV Summary 7

Open charm, beauty at HERAZ. Staykova, V. Aushev, M. Lysovy, P. Thompson, M. Brinkmann, P. Roloff

c, b (+ jets) in DIS and p: powerful test of pQCD

Beauty production:

b in p

Massive NLO pQCD describes the data reasonably well

WG IV Summary 8

Open charm, beauty at HERAZ. Staykova, V. Aushev, M. Lysovy, P. Thompson, M. Brinkmann, P. Roloff

c, b (+ jets) in DIS and p: powerful test of pQCD

Charm production:

Above production threshold (pT>1.5 GeV)

Massive NLO pQCD describes the data reasonably well At threshold!

NLO underestimates data below the threshold

WG IV Summary 9

Open charm, beauty at HERAK.Daum, M. Lysovy, P. Thompson, M. Brinkmann, P. Roloff

Structure functions F2c, F2

b : direct test of g(x)

),()1(1

),( 22

22 QxF

yyQxF cc

Lcccc

−+−∝ compare to NC~F2

Combined F2c:

systematic correlations

accounted for

<F2c> ~ 10%

Compared to HERAPDF1.0:

Band: 1.35<mc<1.6

5

WG IV Summary 10

HERA PDF: additional uncertainty due to variation of 1.4 < mc< 1.65 GeV

The choice of the mc influences

-the gluon PDF,

-most visible in charm PDF,

-consequences for light quarks

HERAPDF1.0 vs HERA F2c : charm mass

A. Cooper-Sarkar

WG IV Summary 11

LHC@10 TeV

What does it mean for LHCchoice of mc=1.65 raises W/Z cross-section predictions at the LHC by ~3%

More significant than other PDF uncertainties (exp. modelmodel, param..)

Larger mc → more gluons, less charm → more light quarks → larger W

Does matter for the Luminosity measurement @ LHC !

A. Cooper-Sarkar

WG IV Summary 12

PDF Fits using HERA F2c data

A. Cooper-Sarkar

usual cuts on data Q2 > 3.5 GeV2, formalism as for HERAPDF1.0

two values of charm mass mc=1.4 GeV and mc=1.65 GeV compared

PDF Fit to charm data prefer mc=1.65 GeV

WG IV Summary 13

PDF Fits using HERA F2c data: test scheme

R. Thorne, A. Cooper-Sarkar

standard

optimal

MSTW prescription for HF treatment

Q2

Test optimal MSTW

Smoother gluon: smaller F2c compensate by smaller mc: obvious effect

Do we learn something?

HQ treatment is crucial for PDF fits

Use charm data to test different schemes @ fixed mc

WG IV Summary 14

Heavy quark production in N (NOMAD)

Statistic uncertainty 3 - 6%, Systematic uncertainty 2%

Largest charm di- data sample close to charm threshold

• most precise measurement σμμ/σCC

(E 6 GeV)

R. Petti

WG IV Summary 15

Heavy quark production in N (NOMAD)

NOMAD di- data in global PDF fits

improves the accuracy of the strange sea

and of the charm quark mass by a factor 2

(E 6 GeV)

R. Petti

Largest charm di- data sample close to charm threshold

• most precise measurement σμμ/σCC

• sensitivity to strange see at high x

WG IV Summary 16

Heavy Quarks in e+e- : test SMBaBar, Belle:

D-Measurements:

• Decay constant fDs: overlap between wave function of light and heavy quarks

BaBar: new measurement closer to Lattice QCD prediction

• Charm mixing and CP in D0, D0 : BaBar: mixing parameters closer to SM

BaBar, Belle: many channels investigated, no evidence for CP violation in D-channel

• No signal for T-violation in D0K+K-+-

B-Measurements:

• BV+V polarization: longitudinal polarization fraction is not understood

disagreement between BaBar and Belle persists

• first observation of 4-body charmless baryonic B decays

Youngjoon Kwon, D. Milanes

WG IV Summary 17

Heavy Quarks in heavy ion collisions

• STAR and PHENIX NPE result in 200GeV p+p collisions consistent

• FONLL describes data well

Test collinear factorization

Suppression or enhancement: study of quark-gluon plasma

Wei Xie, G. Odyniec, A. Sickles

WG IV Summary 18

The heaviest quark: Top cross section

Cross-section measurements:

• Test NLO QCD calculations

• Allow the extraction of top pole mass

• Sample validation for other top properties measurements

• Background for Higgs / SUSY search

Top at TEVATRON:

all hadronic

46%

Semi-leptonic

15%dileptons

G. Compostella, S. Chevalier-Thery, Sung Park, J. Adelman G. Petrillo

WG IV Summary 19

Top cross section

Different channels are combined, systematic correlations taken into account

Error systematic dominated, experimental uncertainty ~ model uncertainty

G. Compostella, S. Chevalier-Thery, Sung Park, J. Adelman G. Petrillo

WG IV Summary 20

Top pole masstt prediction depends on mt:

Measured cross section compared to (approximate) NNLO calculations:

Pole top mass can be extracted

D0 ”direct” (3.6 fb-1): mt=174.20.91.5 GeV

G. Compostella, S. Chevalier-Thery, Sung Park, J. Adelman G. Petrillo

WG IV Summary 21

Other top quark propertiesG. Compostella, S. Chevalier-Thery, Sung Park, J. Adelman G. Petrillo

WG IV Summary 22

On the way to HQ at the LHC First D-mesons at LHCb with L=110 b-1

E. Polycarpo Macedo

Charmonium @ L=160 b-1

WG IV Summary 23

On the way to HQ at the LHC

ALICE, ATLAS, CMS:

J. N. Donini, A. Rossi, R. Covarelli, T. Matsushita

K0s

900 GeVDATA

• Rich physics programm

• First understand the detector

WG IV Summary 24

Thanks to all speakers!

Those who made it to come

Those who participated via EVO

Those who agreed to spontaneously feature the talks

only 1 cancelled experimental talk

but many experts missing