The ABC Effect and the Occurrence of a Dibaryon Resonance MIN 2016 - - PowerPoint PPT Presentation

SLIDE 1

BLINDBILD

The ABC Effect and the Occurrence of a Dibaryon Resonance

MIN 2016

Kyoto July 31 – August 2, 2016 Heinz Clement

Fachbereich Physik

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• H. Clement

2 ABC Effect and Dibaryon Resonance

TheABCEffect TheABCEffect

• …

… denotesa denotesalow low massenhancement massenhancement inthe intheM Mππ

ππ ππ ππ ππ ππ ππ ππ

spectrum spectrum of

• fnuclear

nuclear two two pion pion production production

• …

… onlyshowsupindouble

• nlyshowsupindouble

pionic pionicfusion fusion reactions,if reactions,if theproduced theproducedππ ππ pairis pairisisoscalar isoscalar

• …

… isnamedafter isnamedafterA Abashian, bashian,B Boothand

• othandC

Crowe,who rowe,who werethefirsttoobservethisphenomenonin1960 werethefirsttoobservethisphenomenonin1960

• …

… isnowfoundtobe isnowfoundtobestrictlycorrelated strictlycorrelated withthe withthe appearanceofthe appearanceofthedibaryonresonance dibaryonresonance d*(2380) d*(2380)

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• H. Clement

3 ABC Effect and Dibaryon Resonance

TheABCGallery TheABCGallery TheABCGallery

pn→ dπ0π0

@1.1GeV

pn→ dπ0π0

@1.1GeV

dd→ 4Heπ0π0

@1.1GeV

dd→ 4Heπ0π0

@1.1GeV

pd→ 3Heπ0π0

@0.9GeV

CELSIUS-WASA and WASA-at-COSY measurements

b/GeV] ]

2

[GeV/c

• π
• π

M 0.2 0.3 0.4 0.5 0.6 b/GeV] µ [

• π
• π

/dM σ d 5 10 15 20 25

heavier nuclei??

PRL106(2011)202302PLB637(2006)223 PRC86(2012)032201(R)

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• H. Clement

4 ABC Effect and Dibaryon Resonance

The“noABC” Gallery The The“ “no no ABC ABC” ” Gallery Gallery

pp→ dπ+π0

@1.1GeV

pp→ dπ+π0

@1.1GeV

pp→ „2He“ π0π0

@1.3GeV

pp→ „2He“ π0π0

@1.3GeV

pp→ ppπ0π0

@1.3GeV

]

2

[GeV/c

π π

M

0.3 0.4 0.5

)]

2

b/(GeV/c µ [

π π

/dM σ d

200 400 600 800

π π

M

π π

M

[GeV]

π π

M

0.3 0.4 0.5

b/(GeV)] µ [

π π

/dM σ d

20 40

π π

M

welldescribedbytchannel∆∆ ∆∆ ∆∆ ∆∆ process

Phys.Lett. B684(2010)110 Phys.Lett.B 695(2011)115

]

2

[MeV/c

π

+

π

M 300 350 400 450 )]

2

[nb/(MeV/c

• π

+

π

/dM

σ

d 0.2 0.4

π

+

π

M

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• H. Clement

5 ABC Effect and Dibaryon Resonance

WhatisthereasonforABCeffect? WhatisthereasonforABCeffect?

• Checkallobservables:exclusiveand

Checkallobservables:exclusiveand kinematicallycomplete kinematicallycompletemeasurements measurements

• Lookontheenergydependence

Lookontheenergydependence– – inparticular inparticular

• ftotalcrosssection
• ftotalcrosssection

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• H. Clement

6 ABC Effect and Dibaryon Resonance

Isovector Isovector :TotalCrossSections :TotalCrossSections

Phys.Lett.B679(2009)30

N*(1440) ∆∆ ∆∆ ∆∆ ∆∆

∆(1600)(?)

isospin decomposition ⇒ ⇒ ⇒ ⇒

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• H. Clement

7 ABC Effect and Dibaryon Resonance

Isovector Isovector :TotalCrossSections :TotalCrossSections

Phys.Lett.B679(2009)30

N*(1440) ∆∆ ∆∆ ∆∆ ∆∆

∆(1600)(?)

isospin decomposition ⇒ ⇒ ⇒ ⇒

AlvarezRuso,Oset NPA633(1998)519

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8 ABC Effect and Dibaryon Resonance

Isoscalar: Isoscalar: … … thisiswhatweexpected! thisiswhatweexpected!

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• H. Clement

9 ABC Effect and Dibaryon Resonance

Isoscalar: Isoscalar: … … andthisiswhatwefound! andthisiswhatwefound!

Phys.Rev.Lett.102, 052301 (2009)

CELSIUS/WASA

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• H. Clement

10 ABC Effect and Dibaryon Resonance

Isoscalar Isoscalar :ResultsfromWASAatCOSY :ResultsfromWASAatCOSY

“ABC resonance”

Γ Γ Γ Γintr∼ ∼ ∼ ∼50 MeV

M≈ ≈ ≈ ≈ 2.37GeV Γ Γ Γ Γ ≈ ≈ ≈ ≈ 70MeV

Phys.Rev.Lett.106, 242302 (2011)

m=2.37GeV Γ Γ Γ Γ =70MeV

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• H. Clement

11 ABC Effect and Dibaryon Resonance

pn pn→ → → → → → → → d d*

* →

→ → → → → → → ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ → → → → → → → → d dπ π π π π π π π0

0π

π π π π π π π0

• π

π p n

I(JP)=0(3+) M,Γ, Γ Γ, Γ Γ, Γ Γ, Γi∗ Γ ∗ Γ ∗ Γ ∗ Γf,F(q∆∆

∆∆ ∆∆ ∆∆)

Mππ

ππ ππ ππ

Mdπ

π π π0

Θ Θ Θ Θd

*

model

Phys.Rev.Lett.106, 242302 (2011)

]

4

/c

2

[GeV

π π 2

M 0.1 0.2 0.3 ]

4

/c

2

[GeV

π d 2

M 4 4.5 5 1 2 3 π π d → pn

ABCeffect

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• H. Clement

12 ABC Effect and Dibaryon Resonance

t-channel ∆∆ ∆∆ ∆∆ ∆∆

“ABC effect”

ππ ππ ππ ππ ππ ππ ππ ππ invariantmassM invariantmassMππ

ππ ππ ππ ππ ππ ππ ππ

Phys.Rev.Lett.106, 242302 (2011)

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• H. Clement

13 ABC Effect and Dibaryon Resonance

ABCEffect: ABCEffect: Mappingofd* Mappingofd*→ → ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ onM

• nMππ

ππ ππ ππ ππ ππ ππ ππ spectrum

spectrum

• S

S wavedecay: wavedecay:Γ Γd*

d*→ →∆∆ ∆∆ = Γ

= Γ0

0 q

q∆∆

∆∆ Λ

Λ Λ Λ Λ Λ Λ Λ2

2 2 2 2 2 2 2 / (Λ

/ (Λ / (Λ / (Λ / (Λ / (Λ / (Λ / (Λ2

2 2 2 2 2 2 2 +

+ + + + + + + q q∆∆

∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ 2 2 2 2 2 2 2 2)

) ) ) ) ) ) )

• q

q∆∆

∆∆ =

=p p∆

∆1

1 −

− p p∆

∆2

2 =

= p pN1

N1 +

+k k1

1 –

– p pN2

N2 –

– k k2

2 =

=

• =

=q qNN

NN +

+q qππ

ππ

• Fusion

Fusion: :q qNN

NN =0

=0(neglectingFermimotion)

(neglectingFermimotion)

• ⇒

⇒ q q∆∆

∆∆ 2 2 =q

=qππ

ππ 2 2=M

=Mππ

ππ 2 2 –

– 4m 4mπ

π 2 2

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• H. Clement

14 ABC Effect and Dibaryon Resonance

EffectofVertexFunctiononM EffectofVertexFunctiononMππ

ππ ππ ππ ππ ππ ππ ππ Spectrum

Spectrum

• Variationofcutoff

Variationofcutoff parameter parameterΛ Λ: :

• bestfit:

bestfit:

• Λ

Λ =0.16GeV/c =0.16GeV/c

[GeV]

π π

M 0.2 0.3 0.4 0.5 0.6 b/GeV] µ [

π π

/M σ d 1 2 3 4 5

∆ ∆ = 0.60 GeV Λ = 0.30 GeV Λ = 0.20 GeV Λ = 0.15 GeV Λ = 0.10 GeV Λ π π

M

arXiv:1502.07500

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• H. Clement

15 ABC Effect and Dibaryon Resonance

EffectofVertexFunctiononM EffectofVertexFunctiononMππ

ππ ππ ππ ππ ππ ππ ππ Spectrum

Spectrum

• Variationofcutoff

Variationofcutoff parameter parameterΛ Λ: :

• bestfit:

bestfit:

• Λ

Λ =0.16GeV/c =0.16GeV/c

[GeV]

π π

M 0.2 0.3 0.4 0.5 0.6 b/GeV] µ [

π π

/M σ d 1 2 3 4 5

∆ ∆ = 0.60 GeV Λ = 0.30 GeV Λ = 0.20 GeV Λ = 0.15 GeV Λ = 0.10 GeV Λ π π

M

identicaltoΛ Λ Λ Λ∆

∆ ∆ ∆→Nπ π π π !!!

!!! !!! !!!

arXiv:1502.07500

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• H. Clement

16 ABC Effect and Dibaryon Resonance

Non Non FusionTwo FusionTwo PionProduction: PionProduction: np np→ → np npπ π π π π π π π0

0π

π π π π π π π0

• NoABCeffect!

NoABCeffect!

• Naturallyexplainedbyvertex

Naturallyexplainedbyvertex function: function:

• nofusion

nofusion ⇒ ⇒ q qNN

NN≠

≠ 0

• q

q∆∆

∆∆ ≈

≈ q qNN

NN

• ⇒

⇒ enhancementin enhancementin M Mpn

pn spectrum

spectrum

]

2

[GeV/c

π π

M

0.3 0.4 0.5 )]

2

[mb/(GeV/c

π π

/M σ d 0.5 1 1.5 2

]

2

[GeV/c

π π

M

0.3 0.4 0.5 )]

2

[mb/(GeV/c

π π

/M σ d 0.5 1 1.5 2

π π

M

[GeV]

pn

M

1.9 2 2.1 [mb/GeV]

pn

/dM σ d 1 2 3 4

[GeV]

pn

M

1.9 2 2.1 [mb/GeV]

pn

/dM σ d 1 2 3 4

pn

M

arXiv:1502.07500 PLB743(2015)325

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• H. Clement

17 ABC Effect and Dibaryon Resonance

dd dd→ → 4

4He

Heπ π π π π π π π0

0π

π π π π π π π0

• Energydependenceoftotalcross

Energydependenceoftotalcross section section

• showsresonancestructure

showsresonancestructure

• exactlyatthesameexcess

exactlyatthesameexcess energyasinpn energyasinpn→ → d dπ π0

0π

π0

• isbroadenedduetoFermi

isbroadenedduetoFermi motionandcollisiondamping motionandcollisiondamping

• ⇒

⇒ d d*

* obviouslysurviveseven

• bviouslysurviveseven

innuclearsurrounding innuclearsurrounding

excess energy [GeV] 0.2 0.4 0.6 b] µ [ σ 1 2 3

this work CELSIUS CELSIUS-WASA Birmimgham Saclay WASA-at-COSY π π d

[GeV] s 4 4.2 4.4 4.6 4.8 b] µ [ σ 1 2 3

this work CELSIUS CELSIUS-WASA Birmimgham Saclay

mass ∆ ∆

π π He

4

→ dd

PRC86(2012)032201(R)

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• H. Clement

18 ABC Effect and Dibaryon Resonance

hadronicdecays hadronicdecays

[GeV] s 2.2 2.4 2.6 2.8 3 [mb] σ 0.2 0.4 0.6

T [MeV] 2.2 2.3 2.4 2.5

b] µ [ σ

1 10

2

10

3

10

π

• π

pp → pn

2.2 2.3 2.4 2.5

b] µ [ σ

1 10

2

10

3

10

π π pn → pn

pn → → → → d*(2380)

I = 0+1 I = 1 I = 0

dπ π π π+

+ + +π

π π π−

− − −

½ dπ π π π+

+ + +π

π π π0 2 dπ π π π0

0π

π π π0

PRL 112 (2014) 202301 PRC 90 (2014) 035204 PLB 721 (2013) 229 PRL 106 (2011) 242302

2.2 2.3 2.4 2.5

b] µ [ σ

1 10

2

10

3

10

• π

+

π pn → pn

PRC 88 (2013) 055208 PLB 743 (2015) 325

• Phys. Scr. T 166 (2015) 014016

WASA data

→ √s [GeV]

d* d* d*

HADESPLB750(2015)184

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• H. Clement

19 ABC Effect and Dibaryon Resonance

„ „ExperimentumCrucis ExperimentumCrucis“ “ ford ford*

*

• If

Ifd d*

*atrues

atrues channelresonance channelresonance

• ⇔

⇔

• thenalsoaresonanceinthe

thenalsoaresonanceinthenpsystem npsystem

• ⇔

⇔

• tobesensedin

tobesensedinnpscattering npscattering

• ⇔

⇔

• inparticularinthe

inparticularintheanalyzingpower analyzingpower

• ⇔

⇔

• resonanceeffect

resonanceeffect∼ ∼ P P1

1 3 3(

(Θ) Θ)

• i.e.maximalat

i.e.maximalatΘ Θ =90 =900

SLIDE 20

• H. Clement

20 ABC Effect and Dibaryon Resonance

[deg]

*

Θ 50 100 150

• 0.5

0.5

= 2.377 GeV s

New SAID solution

Ay

• Phys. Rev. Lett. 112 (2014) 202301

Ay AngularDistributionatResonance

SP07

SLIDE 21

• H. Clement

21 ABC Effect and Dibaryon Resonance 21

• pn

d p n → → *

• SAIDSP07

EnergyDependence

SLIDE 22

• H. Clement

22 ABC Effect and Dibaryon Resonance

[GeV] s 2.2 2.4 2.6 2.8

y

A

• 0.2

0.2 [GeV]

n

T 1 1.5 2

= 83 deg

cm n

Θ

• pn

d p n → → *

• SAID

NewSAID solutions

• Phys. Rev. Lett. 112 (2014) 202301

EnergyDependence

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• H. Clement

23 ABC Effect and Dibaryon Resonance 23

[GeV] s 2 2.1 2.2 2.3 2.4 2.5 amplitude

• 0.2

0.2 0.4 [GeV]

n

T 0.6 0.8 1 1.2

3

D

3

[GeV] s 2 2.1 2.2 2.3 2.4 2.5 amplitude

• 0.2

0.2 [GeV]

n

T 0.6 0.8 1 1.2 3

G

3 [GeV] s 2 2.1 2.2 2.3 2.4 2.5 amplitude

• 0.2

0.2 0.4 [GeV]

n

T 0.6 0.8 1 1.2

3

∈

Re Im

SP07

New

SAIDPartialWaveAnalysis

• Phys. Rev. Letters 112 (2014) 202301

3D3 – 3G3CoupledPartialWaves

Arganddiagram:

Re

• 0.2
• 0.1

0.1 0.2 Im 0.05 0.1 0.15 0.2

3

D

3 2.50 GeV 2.45 GeV 2.40 GeV 2.35 GeV 2.30 GeV

(a)

PRC90(2014)035204

Polein3D3 at 2380± ± ± ±10 i40± ± ± ±5MeV ⇔ GenuineResonance innpSystem

SLIDE 24

• H. Clement

24 ABC Effect and Dibaryon Resonance

BranchingRatiosfortheDecayof BranchingRatiosfortheDecayof d d*

*(2380)

(2380)

decaychannelbranchingderivedfrom decaychannelbranchingderivedfrom

• d

dπ π π π π π π π0

0π

π π π π π π π0 14 14± ± 1 1%measurement %measurement d dπ π π π π π π π+

+ + + + + + +π

π π π π π π π−

− − − − − − −

23 23± ± 2 2%measurement %measurement pp ppπ π π π π π π π0

0π

π π π π π π π−

− − − − − − −

6 6± ± 1 1%measurement %measurement nn nnπ π π π π π π π+

+ + + + + + +π

π π π π π π π0 6 6± ± 1 1%isospinmirrored %isospinmirrored np npπ π π π π π π π0

0π

π π π π π π π0 12 12± ± 2 2%measurement %measurement np npπ π π π π π π π+

+ + + + + + +π

π π π π π π π−

− − − − − − −

30 30± ± 4 4%measurement(olddata+HADES) %measurement(olddata+HADES) np12 np12± ± 3 3%measurement %measurement (NN (NNπ π π π π π π π) )I=0

I=0

• inprogress

inprogress

hadronicdecays

}

consistentwith consistentwith isospincoupling isospincoupling fora fora∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ ∆∆ inter inter

• mediatesystem

mediatesystem EPJA51(2015)87

SLIDE 25

• H. Clement

25 ABC Effect and Dibaryon Resonance

ExperimentSU(6)QDCSMRGM ExperimentSU(6)QDCSMRGM( (∆∆ ∆∆+CC)|Faddeev +CC)|Faddeev

Dyson&Xuong Dyson&Xuong Goldman,Pingetal.Shen,Zhangetal.|Gal&Gar Goldman,Pingetal.Shen,Zhangetal.|Gal&Garcilazo cilazo

PRl13(1964)815PRC90(2014)064003 PRl13(1964)815PRC90(2014)064003 PRC60(1999)045203 PRC60(1999)045203|

|

PRL111(2013)172301 PRL111(2013)172301 andrefs. andrefs.thereinarxiv:1408.0458| thereinarxiv:1408.0458| NPA928(2014)73 NPA928(2014)73

Comparisontopredictionsfrom Comparisontopredictionsfrom QuarkandHadronModels QuarkandHadronModels

1+0+ 2+ 3+

I=010101 I=010101 01 01 01 01

∆∆ ∆Ν ΝΝ E … ()()

SLIDE 26

• H. Clement

26 ABC Effect and Dibaryon Resonance

Widthofd Widthofd*

*(2380)

(2380)

• Experiment:

Experiment:Γ Γ Γ Γ Γ Γ Γ Γ≈ ≈ ≈ ≈ ≈ ≈ ≈ ≈ 70MeV 70MeV

• (t

(t channel channel∆∆ ∆∆: :≈ ≈ 250MeV) 250MeV)

• QDCSM:110MeV

QDCSM:110MeV

PRC89(2014)034001 PRC89(2014)034001

• Faddeev:(94+10)MeV

Faddeev:(94+10)MeV

NPA928(2014)73 NPA928(2014)73

• HiddenColor?

HiddenColor?

PLB727(2013)438 PLB727(2013)438

• RGM(

RGM(∆∆ + ∆∆ + CC)69MeV CC)69MeVPRC91(2015)064002

PRC91(2015)064002

SLIDE 27

• H. Clement

27 ABC Effect and Dibaryon Resonance 27

SLIDE 28

• H. Clement

28 ABC Effect and Dibaryon Resonance

EstimateofSize EstimateofSize

• Piccinini

Piccinini(Erice2015,PRL103(2009)162001)

(Erice2015,PRL103(2009)162001)

• R=

R=ħ ħc/ c/√ √ 2 2µ µB B

• X(3872)

X(3872) d d*

*(2380)

(2380)

• D

D– – D D*

*

∆ ∆ − − ∆ ∆

• B=3keVB=80MeV

B=3keVB=80MeV

• ⇒

⇒ R R≥ ≥ 10fmR 10fmR≈ ≈ 0.5fm 0.5fm

SLIDE 29

• H. Clement

29 ABC Effect and Dibaryon Resonance 29

• L=2

L=0

• F. Huang et al, arXiv:1408.0458

1505.05395

1.

0.8fm

QuarkModel

SLIDE 30

• H. Clement

30 ABC Effect and Dibaryon Resonance

R Rè èsum sumè è

1+0+ 2+ 3+

I= I= 0123 0123

∆∆ ∆Ν ΝΝ E 0+ 1+

• Non

Non StrangeTwo StrangeTwo BaryonSpectrum BaryonSpectrum

• 3establishedstates:

3establishedstates:3

3S

S1

1 deuterongroundstate

deuterongroundstate

1 1S

S0

0 virtualstate

virtualstate

1 1D

D2

2 resonance(

resonance(∆ ∆N) N)

• 1new

1new presumablyexotic presumablyexotic state: state: d d*

*(2380)resonance

(2380)resonance(∆∆) (∆∆)

• Aretheremorestates?

Aretheremorestates?

• NN

NN decoupledstateswithI=2,3? decoupledstateswithI=2,3?

• Searchinpp

Searchinpp→ → pp ppπ π+

+ π

π−

−

andinpp andinpp→ → pp ppπ π+

+π

π+

+ π

π−

−π

π−

−

Dyson‘s prediction Gal&Garcilazo Huang,Ping,Wangetal. Zhang,Chen,Shenetal.

SLIDE 31

• H. Clement

31 ABC Effect and Dibaryon Resonance

Summary Summary

• d

d*

*(2380)establishedasa

(2380)establishedasagenuine genuine s s channel channel resonance resonance

• Itisthefirstunambiguouslydetected

Itisthefirstunambiguouslydetectednon non trivial trivial dibaryonstate. dibaryonstate.

• Itcouldbea

Itcouldbeacompact compact hexaquarkstate hexaquarkstate– – butthis butthis needsexperimentalverification. needsexperimentalverification.

• ABCeffect

ABCeffect isjusta isjustamappingofthed mappingofthed*

*→

→ ∆∆ ∆∆ vertex vertex

SLIDE 32

• H. Clement

32 ABC Effect and Dibaryon Resonance

OutlookandOpenProblems OutlookandOpenProblems

• Sizeofd

Sizeofd*

*(2380)

(2380)

• ⇒

⇒ elmexcitationofd elmexcitationofd*

*γ

γd d→ → d d*

* →

→ pn pn

• →

→ d dπ π0

0π

π0

• Observationatotherinstallations

Observationatotherinstallations

• HADES@GSI:underway,butno4

HADES@GSI:underway,butno4π π andnoneutrals andnoneutrals

• IHEP??e

IHEP??e+

+e

e

→

→ dd dd*

*at4.3

at4.3– – 4.6GeV?? 4.6GeV??

• KEK,JPARC,others???

KEK,JPARC,others???

• Aretheremore(exotic)dibaryons?

Aretheremore(exotic)dibaryons?

• Mirrorstateofd

Mirrorstateofd*

* …

…,strange,charmeddibaryons ,strange,charmeddibaryons

SLIDE 33

• H. Clement

33 ABC Effect and Dibaryon Resonance

SLIDE 34

• H. Clement

34 ABC Effect and Dibaryon Resonance

d*

Furtherhints: Furtherhints:γ γ γ γ γ γ γ γd d→ → → → → → → → pn pn

34

R.GilmanandF.GrossAIPConf.Proc.603(2001)55 K.Wijesooriyaetal.,Phys.Rev.Lett.86(2001)2975 T.Kamae,T.FujitaPhys.Rev.Lett.38(1977)471 H.Ikedaetal.,Phys.Rev.Lett.42(1979)1321

d*

→ → → →

d*

SLIDE 35

• H. Clement

35 ABC Effect and Dibaryon Resonance

WASA4 WASA4π π π π π π π π Detector Detector

π π

p

d

γ γ

nγ

γ