successes and problems of chiral soliton approach to exotic baryons kias-hanyang joint workshop on...
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Successes and problems of chiral soliton approach
to exotic baryons KIAS-Hanyang Joint Workshop on
Multifaceted Skyrmions and Effective Field Theory
October 25 - 27, 2004
Michał Praszałowicz - Jagellonian University
Kraków, Poland
Oct. 25, 2004 M. Praszałowicz (Kraków) 2
Wh
at
will
hap
pen
to t
his
en
try
in P
DG
?
3
Experimental evidence forstrange baryon +
Final state:
K0 + p
K+ + n
K0 + p ?
light + is predictedin chiral models
typical QM value is1700 - 1800 MeV
Oct. 25, 2004 M. Praszałowicz (Kraków) 4
Do we see + at all ?
Experiments that do not see +:
• HERA-B, H1• STAR & PHENIX (RHIC) - ?• Opal, Aleph, Delphi (LEP) • BES (Beijing)• CDF, Hyper-CP (Fermilab), E690• BaBar• Phase shifts from old K-scattering exps.
mostly high energy inclusive
Oct. 25, 2004 M. Praszałowicz (Kraków) 5
Width
Most experiments give only upper limits:
• CLAS ( p) < 23 MeV• DIANA (K+ Xe) < 9 MeV
However, some other experiments quote errors:
• ZEUS (DIS) 6.1 1.6 MeV• COSY (p p) 18 4 MeV• HERMES (e p) 17 9 3 MeV• DUBNA (bubbl.ch.) 16 4 MeV
Phase shifts: < 2 MeV
2.01.6
Oct. 25, 2004 M. Praszałowicz (Kraków) 6
Spin and parity
Unknown, in most models S =
parity: + - ChSM, correlated QM, QM with flavor dep.forces,
1 lattice
parity: -- uncorrelated QM (but wider), lattice (if at all),
SumRules
12
Oct. 25, 2004 M. Praszałowicz (Kraków) 7
Antidecuplet
Oct. 25, 2004 M. Praszałowicz (Kraków) 8
NA49 @ CERN
Oct. 25, 2004 M. Praszałowicz (Kraków) 9
Spontaneously broken chiral symmetry
constituent quark mass:
How does a low-momentum chirally invariant Lagrangian look like?
however, it is not invariant under chiral transformation
Oct. 25, 2004 M. Praszałowicz (Kraków) 10
Lagrangian
is invariant, because one can absorb chiral rotation into the redefined pseudoscalar meson fields A
Chiral symmetry is spontaneously broken
Goldstone bosons are massless
Spontaneously broken chiral symmetry
Oct. 25, 2004 M. Praszałowicz (Kraków) 11
Spectrum of the Dirac operator
Oct. 25, 2004 M. Praszałowicz (Kraków) 12
Spectrum of the Dirac operator
Oct. 25, 2004 M. Praszałowicz (Kraków) 13
Spectrum of the Dirac operator
Oct. 25, 2004 M. Praszałowicz (Kraków) 14
Spectrum of the Dirac operator
sealevels:
energyincreases
valencelevel:
energydecreases
system stabilzes
Oct. 25, 2004 M. Praszałowicz (Kraków) 15
SU(3) soliton: static solution
hedgehog Ansatz:
Soliton in the Chiral Quark Modelfrom: D.I. Diakonov, hep-ph/0009006
Skyrme limitQM limit true minimum
valence level
sea levels
Oct. 25, 2004 M. Praszałowicz (Kraków) 17
Chiral Quark Model
fermionspions
integrate out quarks
"Skyrme" Model
only pion fields, kinetic term + interaction terms
constituent quarkmass ~ 350 MeV
Oct. 25, 2004 M. Praszałowicz (Kraków) 18
Chiral Quark Model
fermionspions
integrate out quarks
Skyrme Model
only pion fields, kinetic term + interaction terms
constituent quarkmass ~ 350 MeV
Soliton in the Skyrme model is stabilizes by the Sk. term
Oct. 25, 2004 M. Praszałowicz (Kraków) 19
time-dependent rotation
angular velocities:
Quantizing SU(3) Skyrmionand QM
Oct. 25, 2004 M. Praszałowicz (Kraków) 20
x' y'
z'
k - momentum projection on z'
x
y
z
m - momentum projection on z
Wave functions analogy with a symmetric top
QM textbookLandau, Lipschitz: QM &103
~ N D(J)*(',,)
m,k - angular momentum projections
mk
In SU(3) J R = (p,q), m,k (Y,I,I3)however, because of the constraintnot all k's are allowed but onlythose which have k = (Y=1, I,I3)
Oct. 25, 2004 M. Praszałowicz (Kraków) 21
add small moment of inertia
generalized "momenta":
Hamiltonian:
constraint for 0
Quantizing SU(3) Skyrmion and QM
Oct. 25, 2004 M. Praszałowicz (Kraków) 22
Wave functions and allowed states
B S
Y
I3
Oct. 25, 2004 M. Praszałowicz (Kraków) 23
Mass formula
x
first order perturbation in the strange quark massand in Nc:
octet-decupletsplitting
exotic-nonexotic splittingsknown ?
O(1) correctionsto Mcl do not allowfor absolute mass predictions
Oct. 25, 2004 M. Praszałowicz (Kraków) 24
Mass formula
x
first order perturbation in the strange quark massand in Nc:
octet-decupletsplitting
exotic-nonexotic splittingsknown ?
E. Guadagnini Nucl.Phys.B236 (1984) 35
Oct. 25, 2004 M. Praszałowicz (Kraków) 25
Skyrme model spectrum
symmetry breakingHamiltonian is tooprimitive: richerstructure is needed
Oct. 25, 2004 M. Praszałowicz (Kraków) 26
go to higher orders in ms go to higher orders in Nc
Oct. 25, 2004 M. Praszałowicz (Kraków) 27
Yabu-Ando: higher orders in ms
second order:
4 free parameters: Msol, I1, I2 and , but now I2 contributes to nonexotic splittings
fix and then minimize2 with respect to theremaining parameters
GMO YA
H. Yabu, K. Ando, Nucl.Phys.B301 (1988) 601
sensitive to I2
GMO YA
600 650 700 750 8001300
1400
1500
1600
1700
1800
1900(b)
_
3/2
10
N*
+
mas
s [M
eV]
[MeV]400 500 600 700 800 900
900
1000
1100
1200
1300
1400
1500
1600
1700(a)
+
*
*
N
mas
s [M
eV]
[MeV]
threshold
M.P., Phys. Lett. B575 (2003) 234 and talk at the Cracow Workshop
on Skyrmions and Anomalies, Mogilany, Poland, 1987, World Scientific 1987, p.112.
Oct. 25, 2004 M. Praszałowicz (Kraków) 29
Yabu-Ando: higher orders in ms
second order: H. Yabu, K. Ando, Nucl.Phys.B301 (1988) 601
Constraints:
M.P., Phys. Lett. B575 (2003) 234
talk at the Cracow Workshop on Skyrmions and Anomalies,
Mogilany, Poland, 1987, World Scientific 1987, p.112.
Oct. 25, 2004 M. Praszałowicz (Kraków) 30
go to higher orders in ms go to higher orders in Nc
31
QM breaking hamiltoniancalculate next-to-leading contributions to H'
O(Nc)+O(1) O(1) all O(ms)O(1)
equivalent to Guadagninimass formula:
E. Guadagnini Nucl.Phys.B236 (1984) 35
Oct. 25, 2004 M. Praszałowicz (Kraków) 32
QM breaking hamiltoniancalculate next-to-leading contributions to H'
O(Nc)+O(1) O(1) all O(ms)O(1)
Diakonov, Petrov, Polyakov, Z.Phys A359 (97) 305
richer H':
* no handle on I2
* only 2 linear combinations of parameters
', and enter nonexotic splittings
splittings in 10 10
Oct. 25, 2004 M. Praszałowicz (Kraków) 33
QM breaking hamiltoniancalculate next-to-leading contributions to H'
O(Nc)+O(1) O(1) all O(ms)O(1)
Diakonov, Petrov, Polyakov, Z.Phys A359 (97) 305
richer H':
* no handle on I2
* only 2 linear combinations of parameters
', and enter nonexotic splittings
splittings in 10 10
models give I2 ~ 0.5 fm ~ 400 MeV -1
M10 ~ 1750 MeV M ~ 1450 MeV
34
Antidecuplet in QMricher H': splittings in 10 10 , still no handle on I2
Diakonov, PetrovPolyakov Z.Phys A359 (97)
M10
fixes I2
fixed byN
Oct. 25, 2004 M. Praszałowicz (Kraków) 35
Freedom in QM
NA49
M.M.Pavan, I.I.Strakovsky, R.L.Workman, R.A.Arndt, PiN Newslett. 16 (2002) 110T.Inoue, V.E. Lyubovitskij, T.Gutsche, A.Faessler, arXiv:hep-ph/0311275
M.Diakonov, V.Petrov, M.Polyakov, Z.Phys. A359 (1997) 305
27 -plet
Oct. 25, 2004 M. Praszałowicz (Kraków) 36
Width
Diakonov, Petrov, Polyakov, Z.Phys A359 (97) 305
Weigel, Eur.Phys.J.A2 (98) 391, hep-ph/0006619
G.S. Adkins, C.R. Nappi, E. Witten, Nucl. Phys. B228 (1983) 552
operator V has the same structure as axial current
Oct. 25, 2004 M. Praszałowicz (Kraków) 37
Width in the soliton model
Decuplet decay:
Antidecuplet decay:
In NRQM limit:
SU(3)relations
Oct. 25, 2004 M. Praszałowicz (Kraków) 38
Small Soliton Limit
energy is calculated with respect to the vacuum:
in the small soliton limit only valence level contributes
Diakonov, Petrov, Polyakov, Z.Phys A359 (97) 305
MP, A.Blotz K.Goeke, Phys.Lett.B354:415-422,1995
Oct. 25, 2004 M. Praszałowicz (Kraków) 39
WidthDiakonov, Petrov, Polyakov, Z.Phys A359 (97)
305
Decuplet decay:
Antidecuplet decay:
In small soliton limit:In reality:
< 15 MeV
Oct. 25, 2004 M. Praszałowicz (Kraków) 40
WidthDiakonov, Petrov, Polyakov, Z.Phys A359 (97)
305
Decuplet decay:
Antidecuplet decay:
In small soliton limit:
O(Nc) O(1) O(1) Nc
+ O(1)Is this cancellationconsistent with large Nc counting?
MP Phys.Lett.B583:96-102,2004
Oct. 25, 2004 M. Praszałowicz (Kraków) 41
Three sources of Nc factors:
• quantum Y' = Nc/3• parametric M, I1,2 ~ Nc
• combinatorial SU(3) C-G's for arbitrary Nc
Oct. 25, 2004 M. Praszałowicz (Kraków) 42
Wave functions and allowed states
G. Karl, J. Patera, S. Perantonis,Phys. Lett 172B (1986) 49,J. Bijnens, H. Sonoda, M. Wise,Can. J. Phys. 64 (1986) 1,Z. Duliński, M. Praszałowicz, Acta Phys.Pol. B18 (1988) 1157.
Oct. 25, 2004 M. Praszałowicz (Kraków) 43
Width
MP Phys.Lett.B583:96-102,2004
Oct. 25, 2004 M. Praszałowicz (Kraków) 44
in small soliton limit cancellation takesplace separately in each order in Nc
Width
MP, T. Watabe, K. Goeke Nucl.Phys.A647:49-71,1999
MP Phys.Lett.B583:96-102,2004
Oct. 25, 2004 M. Praszałowicz (Kraków) 45
Mass formula
O(Nc)
O(1/Nc)
O(Nc,ms)
O(Nc,ms)
unknown corrections O(1)
O(1) O(Nc)
+ O(1,ms)
Oct. 25, 2004 M. Praszałowicz (Kraków) 46
O(1)
O(1/Nc)
O(Nc3)
O(Nc3)
O(1/Nc2)
O(1/Nc2)
Width1/5
Oct. 25, 2004 M. Praszałowicz (Kraków) 47
chiral limit:
nonzero meson masses:
Width
Oct. 25, 2004 M. Praszałowicz (Kraków) 48
Matching with the bound state approach
K
Callan, Klebanov Nucl.Phys.B262:365,1985Nadeau, Nowak, Rho, VentoPhys.Rev.Lett.57:2127-2130,1986 Callan, Klebanov , Hornbostel, Phys.Lett.B202:269,1988Itzhaki, Klebanov, Quyang, Rastelli, Nucl.Phys.B684:264-280,2004
K- is bound K+ is not bound and has no smooth limit to rigid rotator
WZ
Oct. 25, 2004 M. Praszałowicz (Kraków) 49
Summary
Collective quantization reproduces known multipletsExotics appears in a natural waySkyrme model indicates that exotics are lightQM has some freedom concerning spectrum
states are narrow, cancellation consistent with Nc
Nc counting is wrong for the widthsreason: phase spacesplittings are O(1)
Is rigid rotator valid in this case?No exotics in bound state approach
Oct. 25, 2004 M. Praszałowicz (Kraków) 51
Comment on the width arithmeticsDiakonov, Petrov, Polyakov, Z.Phys A359 (97) 305 & Jaffe hep-ph/0401187
decreases
width decreasesIn the paper: inverted
Oct. 25, 2004 M. Praszałowicz (Kraków) 52