Ivan Belyaev, LAPP Annecy

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Heavy Flavours
Introduction talk at Heavy Flavour Physics
Session XXXXth Rencontres de Moriond, March
12-19 2005  QCD and Hadronic interactions at
high energy

• Ivan Belyaev, LAPP Annecy

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Heavy Flavours LQCD M

• c b t t
• Heavy
• aS(MQ) is small
• Success of pQCD,
• Impact on HF production in hadronic
  environment
• 1/MQ (LQCD/MQ) expansion
• Success of Heavy Quark Mass Expansion
• Impact on HF decays
• Flavour
• QCD is flavour-blind

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Where Heavy Flavours come from?

• hadronic environment
• CDF, D0, HERA(ep,pA), TeV fixed target
• LHC
• ee- experiments
• BaBaR, Belle, CLEO(-C) , BES,
• Heavy Ion Physics is also interested in Heavy
  Flavours
• Heavy Ion Heavy Flavour ?11.5k documents

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QCD?Heavy Flavours

• Extraction of fundamental EW-CKM parameters is
  impossible without deep understanding of QCD
  effects
• New physics in rare decays

VCKM
u
c
t
d
s
b
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Heavy Flavours ? QCD

• Heavy flavour production at high energy
• Checks for (p)QCD
• Predictions for LHC
• Heavy flavour decays/asymmetries
• Checks for HQE
• extraction of fundamental parameters
• Spectroscopy/bound states
• Checks for QCD models and sometimes theory

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Beauty production at high energy

• HERA H1, ZEUS (ep) 30/920 GeV
• Photoproduction Q2 1 GeV2
• Hard scales Mb, pT
• Deep Inelastic Scattering Q2 gtgt 1 GeV2
• Hard scalesMb, pT, Q2

• Tevatron CDF, D0 vs 2TeV
• hard scales Mb, pT(gt5 GeV/c)

At least 1 hard scale (usully more) pQCD should
work!
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Beauty production at High Energy
D0 Run IIPRL 84(2000) 5478
CDF Run IPRL 85(2002) 5068
Run II Moriond QCD04
Too much beauty?
2004-OK ?
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Heavy Flavour decays

• Heavy Quark Mass Expansion and Operator Product
  Expansion
• G G0 (L/MQ)G1 (L/MQ)2G2(L/MQ)3G3
• Gi are power series as(MQ)
• G0 free quark
• G1 0 for ALL inclusive widths (b?cl-n,
  hadronic, b?sg, b?sll-)
• G2 expressed through
• kinetic energy m2p
• chromomagnetic moment m2G ( MB -MB ?
  m2G/Mb )
• G3 includes Darwin and Spin-Orbital
• non-spectator effects at (1/MQ)3 PI,WE,WA,
• Could be large ( e.g. for charm G(Wc)/G(D)15 )
  

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Recent success

• Lepton energy and hadron mass moments analysis in
  B?Xcln
• Availability of good experimental data
• Progress in theory
• B (B?Xcln)
• s/B 1.6exp?0.6HQE
• Vcb
• s/Vcb 1exp?1HQE?1.5TH
• mb,mc,mb-mc ,m2p,m2G,r3D,r3LS,

BaBaRPRL 93(2004)011803
HQET result for exclusive B?Dln rate at zero
recoil s/Vcb 2exp ? 4TH
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Rare decays?

• HQE works nicely for inclusive rates
• Evaluation of formfactors for exclusive rates is
  difficult
• Note the progress in lattice QCD
• Remarkable exception HQET for B?D()ln
• But experimentally a bit difficult piece of
  phase space
• Exclusive rates often more clean experimentally
  
• more difficult for theory,
• but usually fine for rare decays
• a bit more difficult for experiments

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B?Xsll-

• Theory NNL0 calculation
• Forward backward asymmetry zero is a precision
  test of the Standard Model
• Need HUGE increase of experimental data sets
• SuperB(u,d) and SuperB(u,d,s) factories LHCb 4.4k
  B?K0ll-/year

BaBaRPRL 93(2004)081802
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Radiative Penguins

• Inclusive B ?Xsg
• NNLO calculations in a good shape
• Useful for Vub extraction
• El and MX spectra in B?Xuln
• the same shape function
• exclusive B ?Kg , B?r(w)g
• Vtd/Vts from G(B?r(w)g)/G(B ?Kg)
• better for very large Dms
• experimentally limited
• only by statistics
• TH B (B?r0(w)g)6.5x10-7
• SuperB(u,d,s,..) factories

BELLEPRL 93(2004)061803
BELLEhep-ex/0408137
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New Peaks

• A lot of new peaks (expected and non-expected)
  have been observed recently
• (cc)
• (cs)
• (5q)
• New excited charmed baryons
• Other peaks
• Some of them are already particles
• Other need to be classified
• Particles, molecules, hybrids, Nq , ,
  other beasts
• Fragmentation effects
• Artefacts

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New Particles cs
DsJ (2317)?Dsp0
BaBaRPRL 90(2003)24001

• 2 narrow resonances
• Dsp0 Dsp0
• Isospin violation decays
• Later seen in
• Measure quantum numbers!

DsJ (2463)?Dsp0
CLEOPR D68(2003) 032002
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Expected hc (11P1)

• Searched from 1982
• P-wave hyperfine splitting
• CLEO-C U? y
• Change a flavour after many successful years

CLEOhep-ex/0410090
EXCLUSIVE
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Unexpected X(3872),Y(3940)

• X(3872) and Y(3940)
• discovered in exclusive decays B ?(J/ypp-)K
  and B?(J/ypp-p0)K
• Determination of quantum numbers easy
• (cc) ? D0D0 Molecule? Hybrid?

Y(3940)
X(3872)
BELLEPRL 91(2003)262001
BELLEhep-ex/0408126
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Unexpected X(3940)

• X(3940)
• Discovered in double charmonium production
• ee-?J/y (cc) in J/y recoil mass
• Seems to be different from Y(3940)

BELLEhep-ex/0412041
Hot news!
X(3940)
hc(2S)
cc0
hc
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Threshold structures in B-decays

• 3-body B-decays with baryons show clear
  intriguing structures at threshold (inconsistent
  with phase space)
• New particles?
• Fragmentation dynamics?

BELLEhep-ex/0409010
BELLEhep-ex/0409010
BELLEPRL 89(2002)151802
BELLEhep-ex/0412041
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Instead of Summary

• Heavy Flavours and QCD
• Close (dis)connections
• Good progress in theory
• Theory replaces models in many corners
• B?Xcln, B?Xsg, B?Xsll-,
• Theory is particular advanced for rare decays
• Super B(u,d) factories, LHC,
• Heavy Flavours continue to produce a lot of
  questions
• A lot of new peaks
• Some of them already interpreted as particles
• A lot to do for models and theory
• Fantastic subject for Rencontres de Moriond

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spare

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Beauty production at HERA(pA)

• pA, fixed target
• vs 40 GeV
• Look for b?J/y?ll-
• detached J/y vertices
• Only part of statistics
• 2k