- - PowerPoint PPT Presentation
Maria Beatriz Gay Ducati
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# $%&'(&%% )#'*
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Electroweak Vector boson processes W+ and Z0 production Quarkonium hadroproduction at NLO Application to HeavyIon Collisions Quarkonium production in NRQCD factorization J/psi + gamma Upsilon + gamma Nuclear production Higgs boson production Diffractive factorization Ultraperipheral Collisions
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t t ' α α α + =
Ressonances as observables in t channel t channel trajectory
slope meson exchange Chew and Frautschi (1961) and Gribov (1961) introduced a Regge trajectory with intercept 1 for asymptotic total cross sections This reggeon was named Pomeron ( IP )
INCREASE AT HIGH ENERGIES
Soft Pomeron values (0) ~ 1.09 ’ ~0.25
α α
energy dependence of the diffractive cross section α(0)
P = +1 C = +1 I = 0
IP
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Tevatron/LHC Higgs: NLO W, Z QQ: NRQCD, NLO Tevatron/LHC Higgs: photo-,NLO QQ: NLO
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η θ = − ≈ − + = 2 tan ln ln 2 1
z z
p E p E y
Rapidity
pseudorapidity for a particle with and polar angle θ
η
Inelastic scattering Diffraction defined by leading proton large rapidity gap
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Diffractive production of some objects is possible to be studied Measurement of the ratio of diffractive to nondiffractive production
Jets, W, J/ψ, b ...
All fractions ~ 1% Goulianos Low x 2009
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Study of the diffractive structure function Experimentally determine diffractive structure function
) , ( ) , , ( ) ( ) ( ) , (
2 2
Q x F Q x F ND SD x R
jj D jj jj jj ND SD
ξ σ σ ξ = =
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Described by 5 kinematical variables Bjorken’s x Squared momentum transfer at the lepton vertex
q p Q x . 2
2
=
2 2 2
) ' ( k k q Q − − = − = xs Q y
2
≈
2
) ' ( p p t − − =
2 2 2 2
Q W Q M xIP + + =
M2 is the invariant mass of the X system β is the momentum fraction of the parton inside the Pomeron
2 2 2
Q M Q + = β
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Pomeron exchange
CDF/D0 Collaborations (Tevatron)
630 = s
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Exclusive (dijet)
) , ( ) , , , ( ) γ (
2 * γ 2 *
Q x t x Q x f Xp p
i IP D i i D
σ σ ⋅ = →
i * γ
σ
D i
f
universal hard scattering cross section (same as in inclusive DIS) diffractive parton distribution functions → obey DGLAP universal for diffractive ep DIS (inclusive, dijets, charm)
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(Abachi et al. 1994; Abe et al. 1995)
Structure function of the Pomeron F2
IP(β ,Q2)
Double diffraction Single diffraction Double Pomeron Exchange
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= > <
2 2 2 2 2
| ) , ( | ) , ( | ) , ( | | | b s A b d b s P b s A b d S
s
GAP region of angular phase space devoid of particles Survival probability fulfilling of the gap by hadrons produced in interactions of remanescent particles
probability that no inelastic interaction occurs between scattered hadrons
s
Large Rapidity Gap
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* single diffraction (SD) * central diffraction (CD) * double diffraction (DD)
forward photon spectrometer (calorimeter),
Khoze-Martin-Ryskin Eur. Phys. J. C. 26 229 (2002)
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(f)
15
16
a = Rs / Rh
Gotsman-Levin-Maor PLB 438 229 (1998 - 2002)
a
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explain the exceptionally mild energy dependence of soft diffractive cross sections
radius RH
different methods from GLM model
GLM - arXiv:hep-ph/0511060v1 6 Nov 2005
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Normalization parameter xIP is chosen such that at xIP = 0.003
1 ) ( 2 /
) , (
−
=
t IP t B IP IP p IP
IP IP
x e A t x f
α
t t
IP IP IP
' ) ( ) ( α α α + =
=
min
1 .
/ t t p IP IP
cut
dt f x
) 1 /( | |
2 min IP IP p
x x m t − ≈
proton spectometer (FPS) data
their uncertainties . 1 | | =
cut
t
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distributions obtained from NLO QCD
corresponding to experiment
errors bands experimental uncertainties
experimental and theoretical uncertainties
z is the momentum fraction of
the parton inner the Pomeron
20
MBGD, M. M. Machado, M. V. T. Machado, PRD 75, 114013 (2007)
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! " #
1 ) ˆ ( ˆ 6 ) ( ) (
2 2 2 , 2 2 / / ) (
− Γ = ∑ ∫
+ −A u t M s G V x f x f dE d d
b a W W F ab b p b a p a T e e
η σ
2 2 W
M = µ
[ ]
) 1 ( ˆ
2 −
+ − = A A M E t
W T
∑∫
→ =
b a b p b a p a a b a
t d X Z W p p d x f x f dx dx dx d
, 2 / 2 /
ˆ ) ] / [ ( ˆ ) , ( ) , ( σ µ µ σ
ΓW = 2.06 GeV
dependence in t (u) channel
GF = 1.166 x 10-5 GeV-2
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d
2 2
) ( ˆ
W b a
M p p s = + =
( ) ( )
θ cos 1 2 ˆ ˆ
2
− − = − = s p p t
a c
θ sen M E
W T
2 =
a c
T W
E M A 2 / =
( ) ( ) [ ]
θ θ cos 1 cos 1 4 − − + =
b a L
x x s E
( ) ( ) [ ]
θ θ cos 1 cos 1 4 − + + =
b a e
x x s E
( ) ( )
θ cos 1 2 ˆ ˆ
2
+ − = − = s p p u
b c
A A 1 cos
2 −
± = θ
b
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1 ) ˆ ( ˆ 6 ) ( ) ( ) (
2 2 2 , 2 2 / / ) (
− Γ =∑
∫ ∫
+ −
A u t M s G V x f x f dE x g dx d d
b a W W F ab b p b a IP a T IP IP e e
η σ
W q W q Z qq
e e C θ θ
4 2 2 '
sin | | 4 sin | | 2 2 / 1 + −
parametrization of the IP structure function (H1)
t d ZX ab d s M G C x f x f x f x dx x dx x dx
b a Z F Z ab b p b a IP a IP a a b b IP IP
ˆ ) ( ˆ 2 3 2 ) , ( ) , ( ) (
, 2 2 / 2 /
→ =∑
∫ ∫ ∫
σ π µ µ σ
W
θ
dt t x f x f
IP p IP IP
−
=
/
) , ( ) (
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Tevatron [ sqrt (s) = 1.8 TeV ]
|ηe| < 1.1 1.5< |ηe|<2.5
∫ ∫
− −
− + − +
+ + =
η η η η
σ σ σ σ
W W inc W W
inc diff diff
R
Inclusive Diffractive W- GSPs W+
IS + GSP models Pseudo- rapidity Data (%) R(%) 1.8 TeV Total Total
(*)
− +
→ e e Z
1 . 1 | | <
e
η
5 . 2 | | 5 . 1 < <
e
η ν e W →
55 . 15 . 1 ± 25 . 08 . 1 ±
24 . 64 . ±
25 . 89 . ±
045 . 715 . ± 045 . 715 . ±
875 . 7 . 1 ±
055 . 735 . ±
05 . 71 . ±
80 . 44 . 1 ±
GSP is an average of KMR (S2 = 0.09) and GLM (S2 = 0.086) estimations
* |η|<1.1 CDF D0
25
MBGD, M. M. Machado, M. V. T. Machado, PLB 683, 150-153 (2010)
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state
easy to detect
X + γ + ψ J + p pp / →
X + γ + Υ + p pp →
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Considering the Non-relativistic Quantum Chromodynamics (NRQCD) Gluons fusion dominates over quarks annihilation Leading Order cross section convolution of the partonic cross section with the PDF MRST 2001 LO no relevant difference using MRST 2002 LO and MRST 2003 LO Non-perturbative aspects of quarkonium production
v is the relative velocity of the quarks in the quarkonia
NLO expansions in αs
and three real corrections
28
Negligible contribution of quarks annihilation at high energies
is the center mass energy (LHC = 14 TeV )
J/ψ rapidity 9.2 GeV2
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Cross section written as
invariant mass of J/ψ+γ system
Coefficients are computable in perturbation theory Matrix elements of NRQCD operators
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Bilinear in heavy quarks fields which create as a pair
Q Q
Quarkonium state
ec= 2 3
αs running
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1.16 1.19 x 10-2 0.01 0.01 x m2
c
10.9 0.02 0.136
eb= − 1 3
5 . 4 = m
b
46 . 9 = mΥ
GeV/c2 GeV
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Momentum fraction carried by the Pomeron Squared of the proton's four-momentum transfer Pomeron flux factor Pomeron trajectory
33
Q0
2= 2.5 GeV 2
Cuts for the integration over xIP
0.2 Λ =
QCD
( )
4
2 2 2 ψ T F
m + p =
34
diffractive cross sections
considering GSP (<|S|2>)
ratio into electrons
20 1 ≤ ≤
T
p
at LHC
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cross section
ratio into electrons
strongly dependent
without GSP (<|S|2>)
different sets of diffractive gluon distribution (H1) Quark mass NRQCD matrix elements Factorization scale
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strongly dependent
without GSP (<|S|2>)
different sets of diffractive gluon distribution (H1) Quark mass NRQCD matrix elements Factorization scale
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Slightly large diffractive ratio in comparison to **
[σ] = pb considering FIT A
** C. S. Kim, J. Lee and H. S. Song, Phys Rev D59 (1999) 014028
This work Ref ** <|S|2>=0.06
Renormalized Pomeron flux Q2 evolution in the gluon density No Q2 evolution in the gluon density
( )
4
2 2 ψ T F
m + p =
in our results
T F
E =
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MBGD, M. M. Machado, M. V. T. Machado, PRD. 81, 054034 (2010) MBGD, M. M. Machado, M. V. T. Machado, PRC. 83, 014903 (2011)
40
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Partonical cross section
are the parton distributions inner the hadron i=1 and j=2
factorization (renormalization) scale
( )
R F
s x x s
2 1
=
42
g + Q + Q g + g →
Running of the coupling constant n1f = 3 (4) charm (bottom)
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a0 0.108068 a1
a2 0.0428630 a3 0.131429 a4 0.0438768 a5
a6
a7
Auxiliary functions
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Pomeron flux factor Pomeron Structure Function (H1)
β= x xIP
KKMR model <|S|2> = 0.06 at LHC single diffractive events Parametrization of the pomeron flux factor and structure function H1 Collaboration
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Inclusive nuclear cross section at NLO
APbPb = 208 (5.5 TeV); 40 (6.3) TeV
Heavy quarks cross sections in NLO to pp collisions GSP value decreases the diffractive ratio (<|S|2> = 0.06)
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Suppression factor σpA ~ 0.8 mb (charm) Similar results that
0287 .
2
=
GAP
S
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Coherent Pomeron emmited by the nucleus Predictions to cross sections possible to be verified at the LHC Inclusive cross section Diffractive cross sections Very small diffractive ratio Nucleus-Nucleus collision
A + [LRG] + A + X A + A →
APb = 240
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No values to <|S|2> for single diffractive events in AA collisions Estimations to central Higgs production <|S|2> ~ 8 x 10-7 Values of diffractive cross sections possible to be verified experimentally
Incoherent Pomeron emmited by a nucleon inner the nucleus
*
A + [LRG] + A + X A + A →
APb = 240
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Ingelman-Schlein Bialas-Landshoff
pp collisions LHC (14 TeV)
Ingelman-Schlein > Bialas-Landshoff AA collisions LHC CaCa (6.3 TeV) PbPb (5.5 Tev)
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MBGD, M. M. Machado, G. G. Silveira, PRD. 83, 074005 (2011)
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Standard Model (SM) of Particle Physics has unified the Eletromagnetic interaction and the weak interaction; Particles acquire mass through their interaction with the Higgs Field; Existence of a new particle: the Higgs boson The theory does not predict the mass of H; Predicts its production rate and decay modes for each possible mass;
H
gap gap
η η η η
Exclusive diffractive Higgs production pp → p H p : Inclusive diffractive Higgs production p p → p + X + H + Y + p :
Albert de Roeck X BARIONS (2004)
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LHC opens a new kinematical region: CM Energy in pp Collisions: 14 TeV 7x Tevatron Energy Luminosity: 10 – 100 fb-1 10 x Tevatron luminosity
The TEVNPH Working Group, 1007.4587 [hep-ph]
Evidences show new allowed mass range excluded for Higgs Boson production Tevatron exclusion ranges are a combination
D0
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collisions
triangular loops of top quarks
Lowest order to gg contribution
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Lowest order partonic cross section expressed by the gluonic width of the Higgs boson gg invariant energy squared
Quark Top
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Lowest order two-gluon decay width of the Higgs boson Gluon luminosity PDFs MSTW2008 Lowest order proton-proton cross section Renormalization scale s invariant pp collider energy squared
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Coefficient contributions from the virtual two-loop corrections Regularized by the infrared singular part of the cross section for real gluon emission Infrared part Finite τQ dependent piece
Logarithmic term depending on the renormalization scale
57
QCD coupling in the radiative corrections and LO cross sections
renormalization scale factorization scale M
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F+ : usual + distribution Considering only the heavy-quark limit Region allowed by Tevatron combination
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Gluon radiation two parton final states Invariant energy in the channels New scaling variable supplementing and The final result for the pp cross section at NLO Renormalization scale in αs and the factorization scale of the parton densities to be fixed properly
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Single diffractive Double Pomeron Exchange
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Normalization Gluon distributions in the proton
β= x xIP Single diffractive
H1 parametrization (2006)
Double Pomeron Exchange
Momentum fractions: pomeron and quarks Gluon distributions (i ) in the Pomeron IP Pomeron flux
MSTW (2008)
62
63
GLM KKMR
64
MBGD, G. G. Silveira, Phys. Rev. D 78, 113005 (2008) MBGD, G. G. Silveira, Phys. Rev. D 82, 073004 (2011)
65
Durham Model
p H p pp + + →
2 3 2 2
16 b M dy d π σ =
GF is the Fermi constant and
2 2 T T
Q Q − ≡
$ % &
Khoze, Martin, Ryskin, EPJB 401, 330 (1997)
66
integrated gluon distribution
( ) ( )
2
ln , , Q Q x G K Q x f ∂ ∂ ≡
( ) ( )
2 2 1 4 2 2
, , 9 2 ≈
T T T T F s
Q x f Q x f Q Q d b G dy d α σ
J.R. Forshaw, arXiv:0508274[hep-ph]
67
emissions from the production vertex;
gluon
J.R. Forshaw, arXiv:0508274[hep-ph]
68
( ) ( )
2 2 1 4 2 2
, ~ , ~ 9 2 ≈
T T T T F s
Q x f Q x f Q Q d b G dy d α σ
30x
69
70
proton; Dipole contribution
71
72
with photon fluxes
for its emission from a hadron under collision
73
pp
Estimations for the GSP in the LHC energy MH = 120 GeV Cross section = 1.77-6 fb
74
Process Events/yr BR(H→bb-bar) = 72%
75
GFPAE has been working in hard diffractive events Use of IS with absorptive corrections (gap survival probability) describe Tevatron data for W+ and Z0 production rate production for quarkonium + photon at LHC energies predictions for heavy quark production (SD and DPE) at LHC energies possible to be verified in AA collision (diffractive cross section in pp, pA and AA collisions ) A = Lead and Calcium Higgs predictions in agreement with Hard Pomeron Exchange
C C B B
R(J/ψ)
SD = 0,8 – 0,5 %
R(Υ)
SD = 0,6 – 0,4 %(first in literature)
Cross sections of Higgs production 1 fb (DPE); 60-80 fb (SD)
76
Exclusive photoproduction is promising for the LHC strong suppression of backgrounds cross section prediction fb expecting between 1 and 6 events per year additional signature with the Hγ associated production High event rates for pA collisions σ = 1 pb pPb collisions
77 77
Gap survival probability for nuclear collisions Dijets in hadronic and nuclear collisions ...
DIFFRACTION IN NUCLEAR COLLISIONS
78 78
79
6 6 ≤ ≤ − η
311 .
1 1 1 1
= =
− − inclusive e diffractiv KMR
R σ σ
Large range of pseudorapidity High diffractive ratio
80
nucleon form-factor Double Pomeron Exchange
Differential phase-space factor mass of produced quarks
81
two-dimensional four-vectors describing the transverse component of the momenta Sudakov parametrization for momenta momentum for one of exchanged gluons momenta for the incoming (outgoing) protons momentum for the produced quark (antiquark)
82
Square of the invariant matrix element averaged over initial spins and summed
effect of the momentum transfer dependence
83 83
invariants, s and t, Mandelstam variables
( ) ( ) ( ) ( )
2 2 2 2
D B C A t D C B A s − = − = + = + =
( )
t m g t s A − ≈
2 2
,
π
Square of center-of-mass energy Square of the transfered four momentum
( ) ( )
s t A t s A
D B C A CD AB
, ,
→ →
=
by crossing symmetry pion exchange g coupling constant Singularity (pole) in non-physical region t > 0 in s-channel diagram where s t
A B D C D A B C
2 π
m t =
84 84
A(s,t)
85 85
≈
X el
s dt d
2
1 σ
5 . ) ( , 1 ) ( ≤ + ≈ α ε α
( ) 1
Im 1
− =
≈ ≈
α
σ s A s
AB el AB tot
Consider elastic A B A B by Regge
Apparent contradiction vacuum trajectory Pomeron αIP (t) vacuum quantum numbers
=
X tot
s 2 1 σ
2
1 s ≈
2 ) ( 2 −
≈
t
s α
=
X
s 2 1
s 1 ≈
A A B B
X
2 2
A A B B A B
X
A A A A B B B B
α(t) α(0)
86 86
t t
IP
25 . 085 . 1 ) ( + = α
, → ∞ → s t s
1
) ( ) (
−
≈
IP
s
BIP AIP AB tot α
β β σ
2 2 2 2
16 ) ( ) (
−
≈
IP
s t t dt d
BIP AIP AB tot α
π β β σ
(p p, p p)
The interactions described by the exchange of a IP are called diffractive
so βiIP Pomeron coupling with external particles Valid for High s
87 87
No diffraction within a black disc It occurs only at periphery, b ~ R in the Froissart regime, Unitarity demands i.e. DonnachieLandshoff approach may not be distinguishable from logarithmic growth Any sλ power behaviour would violate unitarity At some point should be modified by unitarity corrections
( )
s R ln ∝
88 88
no evolution in Q2
Ael (t)
and
What is the Pomeron?
∝
89 89
hadronhadron interactions
SOFT low momentum transfer
HARD high momentum transfer
Gluon exchange
“hard” Pomeron)
90 90
Many measurements in pp Pomeron exchange trajectory Pomeron universal and factorizable applied to total, elastic, diffractive dissociation cross sections in ep collisions
91 91
DDIS differential cross section can be written in terms of two structure functions Dependence of variables x, Q2, xIP, t Introducing the longitudinal and transverse diffractive structure functions DDIS cross section is
) 4 ( 1 D
F
) 4 ( 2 D
F
and
) 4 ( 1 ) 4 ( 2 ) 4 (
2
D D D L
xF F F − =
) 4 ( 1 ) 4 (
2
D D T
xF F =
( ) [ ] ( )
t x Q x F t x Q x R y y xQ dt dx dxdQ d
IP D IP D em IP D p
, , , , , , 1 2 1 4
2 ) 4 ( 2 2 ) 4 ( 2 4 2 2
*
+ + − = πα σ γ
) 4 ( ) 4 ( ) 4 ( D T D L D
F F R =
92 92
Data are taken predominantly at small y Cross section little sensitivy to RD(4)
) 4 ( ) 4 ( D T D L
F F <<
( )
t x Q x F y y xQ dt dx dxdQ d
IP D em IP D p
, , , 2 1 4
2 ) 4 ( 2 2 4 2 2
*
+ − = πα σ γ
) 4 ( 2 D
F
( )
dt dx d Q t x Q x F
IP D p em IP D
*
2 2 2 ) 4 ( 2
4 , , ,
γ
σ πα =
) 4 ( 2 D
F
dt dx t x Q x dF F
IP IP D D
) , , , (
2 2 ) 4 ( 2
≡
D
F2
is dimensionless
93 93
When the outgoing proton is not detected
no measurement of t
Only the cross section integrated over t is obtained The structure function is defined as
( )
IP D em IP D p
x Q x F y y xQ dx dxdQ d , , 2 1 4
2 ) 3 ( 2 2 4 2 2
*
+ − = πα σ γ
) 4 ( 2 D
F
( ) ( )
t x Q x F t d x Q x F
IP D IP D
, , , | | , ,
2 ) 4 ( 2 2 ) 3 ( 2
∞
=
94 94
Factorization theorem holds for diffractive structure functions These can be written in terms of the diffractive partons distributions It represents the probability to find a parton in a hadron h, under the condition the h undergoes a diffractive scattering QCD factorization formula for is
Probability to find in a proton a parton of type i carrying momentum fraction ξ Under the requirement that the proton remains intact except for a momentum transfer quantified by xIP and t
D
F2 = ∑∫
2 2 2 ^ 2 2 2
, , ) , , , ( ) , , , ( µ ξ µ ξ ξ Q x F dt dx t x df d dt dx t x Q x dF
i i IP IP i x x IP IP D
IP
dt dx t x df
IP IP i
/ ) , , , (
2
µ ξ
95 95
Perturbatively calculable coefficients Factorization scale
X2 = M2
Diffractive parton distributions satisfy DGLAP equations Thus “ ” is a diffractive parton distribution integrated over t
2 2 2
, ξ ˆ Q x F i
= ∂ ∂
j IP IP j s ij IP IP i
dt dx t x df P d dt dx t x df ) , ,
ξ ( )
α , ς ξ ς ς ) , ,
ξ (
2 1 ξ 2 2
∞ −
=
IP N IP
x m x IP IP i IP IP i
dt dx t x df t d dx x df
1 2 2
2 2
) , ,
ξ ( ) ,
ξ (
96 96
It is quite usual to introduce a partonic structure for At Leading Order Pomeron Structure Function written as a superposition
carried by its partonic constituents
inside the Pomeron This interpretation makes sense only if we can specify unambigously the probability of finding a Pomeron in the proton and assume the Pomeron to be a real particle (Ingelman, Schlein, 1985)
IP
F2
IP
x x = β ) , (
2
Q q IP β
=
q q IP q IP
Q q e Q F
, 2 2 2 2
) , ( ) , ( β β β
97 97
Diffractive quark distributions and quark distributions of the Pomeron are related
Function acquires a term containing
) , (
2
Q g IP β
) , (
2
Q g IP β
dt dx df
IP g /
) , ( | ) ( | 16 1 ) , , , (
2 ) ( 2 2 2 2
Q g x t g dt dx t x Q df
IP t IP IP IP IP g
IP
β π β
α −
= ) , ( | ) ( | 16 1 ) , , , (
2 ) ( 2 2 2 2
Q q x t g dt dx t x Q df
IP t IP IP IP IP q
IP
β π β
α −
=
Representation of D* diffractive production in the infinite-momentum frame description of DDIS
98 98
Hadronic processes can be characterized by an energy scale Soft processes – energy scale of the order of the hadron size (~ 1 fm) pQCD is inadequate to describe these processes Hard processes – “hard” energy scale ( > 1 GeV2) can use pQCD “factorization theorems” Separation of the perturbative part from nonperturbative Most of diffractive processes at HERA !" """#
99 99
IP flux Structure function
( )
) , ( , , , ,
2 2 2 ) 4 ( 2
Q F t x f t x Q x F
IP IP p IP IP D
β =
IP
Data Good fit with added Reggeon for HERA
see MBGD & M. V. T. Machado 2001
Born graphs in the abelian and nonabelian (QCD) cases look like
100 100
total cross sections implies
2 '
25 .
−
≈ GeV
IP
α
1 ) ( ≈
IP
α
Reggetype
( )
[ ]
2 ) ( 2 2
exp ) (
+
=
t
IP
W t b W dt d
α
σ
First measurements in hh scattering
( ) ( )
t t ' α α α + =
α(0) and α’ are fundamental parameters to represent the basic features of strong interactions α’ energy dependence of the transverse system
) exp( ) (
4 ) ( 4
bt W W dt d
−
=
α
σ
) ln( ' 4 W b b α + =
101
singlet distribution Σ(z)
subprocess with respect of the diffractive exchange
higher order processes
− − − = ) 1 ( 01 . exp ) 1 ( ) , (
2 /
z z z A Q z zf
i i
C B i IP i
102
to the Bg parameter
0 =
1.75 GeV2)
done with Cg = 0
(Q2
0 = 2.5 GeV2)
2 2
5 . 8 ; 2 , 8 . GeV Q GeV M X < > < β
103
and their uncertainties, as used in the QCD fits.
are varied simultaneously to obtain the theoretical errors on the fits (as well as α’IR and BIR).
independently.
parameters of the fit are sensitive to the variation of the parametrization scale Q2
α8
(5) (MZ 2)
mb mc BIR α’IR αIR(0) BIP α’IP Value Parameter
DESY – 06-049 May 2006
2 19 . 06 .
06 .
− + −
GeV
2 . 2 7 .
5 . 5
− + −
GeV 10 . 50 . ±
2 6 . 3 .
3 .
− + −
GeV
2 6 . 1 4 .
6 . 1
− + −
GeV GeV 2 . 4 . 1 ± GeV 5 . 5 , 4 ± 002 . 118 . ±