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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

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Page 1: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 2: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 2

Wh

at

will

hap

pen

to t

his

en

try

in P

DG

?

Page 3: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

3

Experimental evidence forstrange baryon +

Final state:

K0 + p

K+ + n

K0 + p ?

light + is predictedin chiral models

typical QM value is1700 - 1800 MeV

Page 4: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 5: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 6: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 7: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 7

Antidecuplet

Page 8: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 8

NA49 @ CERN

Page 9: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 10: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 11: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 11

Spectrum of the Dirac operator

Page 12: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 12

Spectrum of the Dirac operator

Page 13: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 13

Spectrum of the Dirac operator

Page 14: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 14

Spectrum of the Dirac operator

sealevels:

energyincreases

valencelevel:

energydecreases

system stabilzes

Page 15: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 15

SU(3) soliton: static solution

hedgehog Ansatz:

Page 16: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Soliton in the Chiral Quark Modelfrom: D.I. Diakonov, hep-ph/0009006

Skyrme limitQM limit true minimum

valence level

sea levels

Page 17: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 18: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 19: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 19

time-dependent rotation

angular velocities:

Quantizing SU(3) Skyrmionand QM

Page 20: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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)

Page 21: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 21

add small moment of inertia

generalized "momenta":

Hamiltonian:

constraint for 0

Quantizing SU(3) Skyrmion and QM

Page 22: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 22

Wave functions and allowed states

B S

Y

I3

Page 23: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 24: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 25: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 25

Skyrme model spectrum

symmetry breakingHamiltonian is tooprimitive: richerstructure is needed

Page 26: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 26

go to higher orders in ms go to higher orders in Nc

Page 27: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 28: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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.

Page 29: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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.

Page 30: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 30

go to higher orders in ms go to higher orders in Nc

Page 31: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 32: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 33: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 34: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 35: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 36: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 37: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 37

Width in the soliton model

Decuplet decay:

Antidecuplet decay:

In NRQM limit:

SU(3)relations

Page 38: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 39: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 40: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 41: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 42: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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.

Page 43: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 43

Width

MP Phys.Lett.B583:96-102,2004

Page 44: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 45: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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)

Page 46: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 46

O(1)

O(1/Nc)

O(Nc3)

O(Nc3)

O(1/Nc2)

O(1/Nc2)

Width1/5

Page 47: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 47

chiral limit:

nonzero meson masses:

Width

Page 48: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 49: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 50: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October
Page 51: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

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

Page 52: Successes and problems of chiral soliton approach to exotic baryons KIAS-Hanyang Joint Workshop on Multifaceted Skyrmions and Effective Field Theory October

Oct. 25, 2004 M. Praszałowicz (Kraków) 52