Heavy Flavours

Ivan Belyaev, LAPP Ivan Belyaev, LAPP AnnecyAnnecy

Heavy Flavours

Introduction talk at Heavy Flavour Physics SessionIntroduction talk at Heavy Flavour Physics Session

XXXXXXXXthth Rencontres Rencontres de Moriond, March 12-19 2005 de Moriond, March 12-19 2005

““QCD and Hadronic interactions at high energy”QCD and Hadronic interactions at high energy”

mailto:[email protected]?subject=Heavy%20Flavours%20&%20QCD

mailto:[email protected]?subject=Heavy%20Flavours%20&%20QCD

13 March'2k+513 March'2k+5 ““Heavy Flavours ”Heavy Flavours ” Ivan BelyaevIvan Belyaev 22

Heavy Flavours: QCD ≤ M

c b t c b t •““Heavy”Heavy”

• SS(M(MQQ)) is small is small • Success of Success of pQCDpQCD, ,

• Impact on HF production in hadronic Impact on HF production in hadronic environmentenvironment

• 1/M1/MQQ ( (QCDQCD/M/MQQ)) expansion expansion• Success of Heavy Quark Mass ExpansionSuccess of Heavy Quark Mass Expansion

• Impact on HF decays Impact on HF decays

•““Flavour”Flavour”• QCDQCD is “flavour-blind” is “flavour-blind”


Where Heavy Flavours come from?

• hadronic environmenthadronic environment

• CDF, D0, HERA(ep,pA), TeV CDF, D0, HERA(ep,pA), TeV fixed targetfixed target

• LHC LHC

• ee++ee-- experiments experiments

• BaBaR, Belle, CLEO(-C) , BES, …BaBaR, Belle, CLEO(-C) , BES, …

•Heavy Ion Physics is also interested in Heavy Heavy Ion Physics is also interested in Heavy Flavours :Flavours :

• ““Heavy Ion + Heavy Flavour”Heavy Ion + Heavy Flavour” →→11.5k documents11.5k documents


QCD↔Heavy Flavours

•Extraction of fundamental Extraction of fundamental EW-CKMEW-CKM parameters is impossible without deep parameters is impossible without deep understanding of understanding of QCDQCD effects effects

•New physics in rare decays New physics in rare decays

|V|Vcbcb|| B B (B(B→→XXccll)) or or dd(B→D(B→D(*)(*)ll)/dy|)/dy|y=0y=0

|V|Vubub|| BB→→XXuull endpoint endpoint

arg(Varg(Vtdtd)) CP asymmetry in CP asymmetry in BBdd→→J/J/KKSS

BB→→,B,B→→→→, …, …

arg(Varg(Vubub)) rare modesrare modes

|V|Vtdtd/V/Vtsts|| mmdd//mmss or or (B(B→→B B →→KK**))

arg(Varg(Vtsts)) CP asymmetries in CP asymmetries in BBss decays decays

VVCKMCKM

uu

cc

tt

dd ss bb


Heavy Flavours ↔ QCD

•Heavy flavour production at high energyHeavy flavour production at high energy

•Checks for Checks for (p)QCD(p)QCD

• Predictions for Predictions for LHCLHC

•Heavy flavour decays/asymmetriesHeavy flavour decays/asymmetries

• Checks for Checks for HQEHQE

• extraction of fundamental parameters extraction of fundamental parameters

•Spectroscopy/bound states Spectroscopy/bound states

•Checks for Checks for QCDQCD models and models and sometimessometimes theory theory


Beauty production at high energy

Tevatron Tevatron CDF, D0CDF, D0 √s √s ~~2TeV2TeV

•hard scales: hard scales: MMbb, p, pTT(>5 GeV/c)(>5 GeV/c)

HERA: HERA: H1, ZEUSH1, ZEUS (ep) 30/920 GeV(ep) 30/920 GeV

• Photoproduction Photoproduction QQ2 2 ≤ ≤ 1 GeV1 GeV22

• Hard scales : Hard scales : MMbb, p, pTT

•Deep Inelastic Scattering Deep Inelastic Scattering QQ22 >> 1 >> 1 GeVGeV2 2

•Hard scales:Hard scales:MMbb, p, pTT, Q, Q2 2

At least 1 hard scale (usully more): At least 1 hard scale (usully more): pQCDpQCD should work! should work!


Beauty production at High Energy

Run II Run II Moriond QCD’04Moriond QCD’04D0 Run ID0 Run IIPRL 84(IPRL 84(20002000) 5478) 5478 CDF Run ICDF Run IPRL 85(PRL 85(20022002) 5068) 5068

Too much Too much beauty?beauty?

2004-2004-OK ?OK ?


Heavy Flavour decays

•HHeavy eavy QQuark Mass uark Mass EExpansion and Operator Product Expansionxpansion and Operator Product Expansion

= = 00 + ( + (/M/MQQ))11 + ( + (/M/MQQ))2222+(+(/M/MQQ))3333+…+…

• ii are power series are power series ss(M(MQQ))

• 00 – “free quark” – “free quark”

• 11 = 0 = 0 for for ALLALL inclusive widths ( inclusive widths (bb→→ccll--, hadronic, , hadronic, bb→→ss, b, b→→ssll++ll--))

• 22 expressed through expressed through

• “ “kinetic energy” kinetic energy” 22

• “ “chromomagnetic moment” chromomagnetic moment” 22G G ( M ( MB*B* -M -MB B ≈ ≈ ⅔⅔ 22

GG/M/Mb b ))

• 33 includes Darwin and Spin-Orbital includes Darwin and Spin-Orbital

• ““non-spectator” effects at non-spectator” effects at (1/M(1/MQQ))33 : : PI,WE,WA,…PI,WE,WA,…

• Could be large ( e.g. for charm Could be large ( e.g. for charm ((cc)/)/(D(D++)=~15)=~15 ) )


Recent success

Lepton energy and hadron mass moments analysis in Lepton energy and hadron mass moments analysis in BB→→XXccll

•Availability of good experimental dataAvailability of good experimental data

• Progress in theoryProgress in theory

•B B (B(B→→XXccll))

• //BB : 1.6% : 1.6%expexp0.6%0.6%HQEHQE

• |V|Vcbcb| |

• VVcbcb = 1% = 1%expexp1%1%HQEHQE1.5%1.5%THTH

• mmbb,m,mcc,m,mbb-m-mc c ,,22,,22

GG,,33DD,,33

LS,LS,

HQET HQET result for exclusive result for exclusive BB→→DD**ll rate at zero recoil rate at zero recoil

/|V/|Vcbcb| = 2%| = 2%expexp 4% 4%THTH

BaBaRBaBaRPRL 93(2004)011803PRL 93(2004)011803


Rare decays?

• HQEHQE works nicely for inclusive rates works nicely for inclusive rates

• Evaluation of formfactors for exclusive rates is Evaluation of formfactors for exclusive rates is difficult difficult

•Note: the progress in Note: the progress in latticelattice QCDQCD

• Remarkable exception: Remarkable exception: HQETHQET for for B→DB→D(*)(*)ll • But: experimentally a bit difficult piece of phase spaceBut: experimentally a bit difficult piece of phase space

•Exclusive rates often more “clean” Exclusive rates often more “clean” experimentally experimentally

• more difficult for theory, more difficult for theory,

• but usually fine for but usually fine for rare decaysrare decays

• a bit more difficult for experiments a bit more difficult for experiments


B→Xsl+l-

• Theory Theory NNL0NNL0 calculation calculation

• Forward backward Forward backward asymmetry zero is a precision asymmetry zero is a precision test of the Standard Modeltest of the Standard Model

• Need Need HUGEHUGE increase of increase of experimental data setsexperimental data sets

• SuperBSuperB(u,d)(u,d) and and SuperBSuperB(u,d,s)(u,d,s)

factories factories LHCb 4.4k B→K*0l+l-/year

BaBaRBaBaRPRL 93(2004)081802PRL 93(2004)081802


Radiative Penguins

•Inclusive Inclusive B B →→XXss

• NNLONNLO calculations in a good shape calculations in a good shape

• Useful for Useful for |V|Vubub|| extraction extraction • EEll and and MMXX spectra in spectra in →→XXuull

• the same shape function the same shape function

•exclusive exclusive B B →→KK** , B , B→→• |V|Vtdtd/V/Vtsts|| from from (B(B→→B B →→KK**))

• better for very large better for very large mmss

• experimentally limited experimentally limited only by statisticsonly by statistics

•TH: TH: B B (B(B→→00)=6.5x10)=6.5x10-7-7

• SuperBSuperB(u,d,s,..)(u,d,s,..) factories factories

BELLEBELLEPRLPRL 93(2004)06180393(2004)061803

BELLEBELLEhep-ex/0408137hep-ex/0408137


New Peaks

• A lot of new A lot of new peakspeaks (expected and non-expected) (expected and non-expected) have been observed recentlyhave been observed recently

• (cc)(cc)

• (cs)(cs)

• (“5q”)(“5q”)

• New excited charmed baryons New excited charmed baryons

• Other peaks Other peaks

• Some of them are already “particles”Some of them are already “particles”

• Other need to be classified:Other need to be classified:• Particles, molecules, hybrids, Particles, molecules, hybrids, “N”q “N”q , … , other beasts , … , other beasts

• Fragmentation effectsFragmentation effects

•Artefacts Artefacts


New Particles: “cs”

• 2 narrow resonances2 narrow resonances

DDss00 D Dss**00

• Isospin violation decaysIsospin violation decays

•Later seen in Later seen in

•Measure quantum numbers!Measure quantum numbers!

DDsJsJ (2463) (2463)→D→Dss**00

DDsJsJ (2317) (2317)→D→Dss00BaBaRBaBaRPRL 90(2003)24001PRL 90(2003)24001

CLEOCLEOPRPR D68(2003) 032002D68(2003) 032002


“Expected”: hc (11P1)

•Searched from 1982 Searched from 1982

• PP-wave hyperfine splitting-wave hyperfine splitting

• CLEO-C:CLEO-C: →→ •Change a flavour after many Change a flavour after many

successful yearssuccessful yearsEXCLUSIVEEXCLUSIVE

CLEOCLEOhep-ex/0410090hep-ex/0410090


“Unexpected”: X(3872),Y(3940)

X(3872X(3872) and ) and Y(3940)Y(3940)

•discovered in exclusive decays discovered in exclusive decays BB →→((J/J/++--)K )K and and BB→→(J/(J/00)K)K

•Determination of quantum numbersDetermination of quantum numbers “easy”“easy”

((cccc) ? ) ? DD*0*0DD00 Molecule? Hybrid? Molecule? Hybrid?

Y(3940)Y(3940)X(3872)X(3872) BELLEBELLEPRLPRL 91(2003)26200191(2003)262001



“Unexpected”: X(3940)

• X(3940)X(3940)

•Discovered in double charmonium production Discovered in double charmonium production

ee++ee--J/J/(cc) (cc) in in J/J/ recoil mass recoil mass

•Seems to be different from Seems to be different from Y(3940)Y(3940)

c0c0

cc(2S)(2S)

X(3940)X(3940)

cc

Hot news! Hot news! BELLEBELLEhep-ex/0412041hep-ex/0412041


Threshold structures in B-decays

• 3-body 3-body BB-decays with -decays with baryons show clear intriguing baryons show clear intriguing structures at threshold structures at threshold (inconsistent with phase (inconsistent with phase space)space)

• New particles? New particles?

• Fragmentation dynamics?Fragmentation dynamics?




BELLEBELLEPRL 89(2002)151802PRL 89(2002)151802


Instead of Summary

•Heavy Flavours and QCDHeavy Flavours and QCD•Close (dis)connectionsClose (dis)connections

•Good progress in theory:Good progress in theory:• Theory replaces models in many cornersTheory replaces models in many corners

• BB→→XXccll, B, B→→XXss, B, B→→XXssll++ll--, …, …

• Theory is particular advanced for rare decays Theory is particular advanced for rare decays • Super BSuper B(u,d)(u,d) factories, LHC, … factories, LHC, …

•Heavy Flavours continue to produce a lot of Heavy Flavours continue to produce a lot of questions questions •A lot of new peaks A lot of new peaks

•Some of them already interpreted as particles Some of them already interpreted as particles

•A lot to do for models and theoryA lot to do for models and theory

Fantastic subject for Fantastic subject for “Rencontres de Moriond”“Rencontres de Moriond” … …


spare


Beauty production at HERA(pA)

• pA, pA, fixed targetfixed target

• √√s s ~~ 40 GeV 40 GeV

•Look for Look for bb→→J/J/→→ll++ll--

•detached detached J/J/ vertices vertices

•Only part of statisticsOnly part of statistics

•2k:2k:

nuclnbbb stat /3.12)( 5.3

2.3

nuclnbsysstatbb /)()(32)( 67

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Heavy Flavours