/
Diquarks Diquarks

Diquarks - PowerPoint Presentation

marina-yarberry
marina-yarberry . @marina-yarberry
Follow
352 views
Uploaded On 2015-10-03

Diquarks - PPT Presentation

in heavy baryons Atsushi Hosaka   RCNP Osaka U 91013 2013 Charmed baryons 1 Practical questions of hadron physics How ground and excited states are described Are there simple language for it ID: 148034

charmed baryons 2013 diquark baryons charmed diquark 2013 mode good quark diquarks baryon heavy quarks uds light spectrum bad

Share:

Link:

Embed:

Download Presentation from below link

Download Presentation The PPT/PDF document "Diquarks" is the property of its rightful owner. Permission is granted to download and print the materials on this web site for personal, non-commercial use only, and to display it on your personal computer provided you do not modify the materials and that you retain all copyright notices contained in the materials. By downloading content from our website, you accept the terms of this agreement.


Presentation Transcript

Slide1

Diquarks in heavy baryons

Atsushi Hosaka (RCNP, Osaka U.)

9/10-13, 2013

Charmed baryons

1

Practical questions of hadron physics

• How ground and excited states are described?

• Are there simple language for it

when quarks and gluons interact strongly

• Are there kinds of quasi-particles interacting weakly

• Constituent quarks:

Mere

useful tool of symmetry realization or

Dynamically realistic

and active object

How can

diquarks

be

be identified in

multi-quark systems

Baryons, nuclei, nuclear matter, quark matterSlide2

Quark-diquark baryon

Selem-Wilczek:

e-Print: hep-ph/0602128

ee has repulsive force, BUT

• qq has attractive force 

 

SU(3)

c

: half of qqbar attraction    SU(2)c : Same as qqbar  Pauli-Gursey symmetry ~ several hundred MeV• Diquark can be seen better in heavy baryons than in light

Color magnetic int.

Good

BadSlide3

Some evidences

9/10-13, 2013Charmed baryons

3

• Σ-Λ (80 MeV),

Σc

-Λc (215 MeV) mass difference

• Production rate of

Λ

,

Σ (e+e-@10 GeV) Λ : Σ = 0.08:0.023, Λc : Σc = 0.074:0.014• ΔI = ½ rule • F2n/F2p

 ¼• Lack of exotics Repulsive between g

ood diquarks?Slide4

In QCD

9/10-13, 2013Charmed baryons4

• How

diquarks

are defined? -- correlation function

ud

-diquark

Heavy quark

t

= 0

2

t

t

• How are they observed

in charmed baryons?

Spectrum, decay rate, production

A

re there other opportunities to hunt

diquarks

?

qq interaction in a baryon (colored environment)Slide5

Density correlations

9/10-13, 2013Charmed baryons5

Alexandrou

,

deForcrand

, LuciniPRL 97, 222002 (2006)

cos

θ

1.0

r

θ

r

= 0.69

fm

r

= 0.47

fm

r

= 0.35

fmGood

diquarkBad

diquarkIndicates significant attraction between quarks in good diquark pairSlide6

Baryon spectrum

S=1/2

S=3/2

qqq

qq

c

q

cc

c

I

Light flavor baryons (

uds

)

Ground 8 + 10

and excited

~

80

states

9/10-13, 2013

Charmed baryons

6

udsSlide7

S=3/2

S=1/2

Charmed baryons

14

c

1

cc

<< 80

uds

(6

excited)

1/2

+

1/2

1/2

+

3

/2

+

1/2

1/2

+

3

/2

+

3/2

5/2

+

?

Ξ

C

[

GeV

]

?

1/2

+

3

/2

+

Ω

C

cqq

cqq

csq

css

Ξ

C

Ξ’

C

1

?

1

Ξ

+

cc

9/10-13, 2013

Charmed baryons

7Slide8

Advantage of heavy quark

• Discriminate of modes

Light baryon

One HQ baryon

Two HQ baryon

Spectrum, productions and decays

9/10-13, 2013

Charmed baryons

8Slide9

λ and

ρ motions split  known as isotope shift

s

q

s

q

, SO

Σ

c

(1/2-,3/2-)

Λ

c

(

1/2-

,1/2-

3/2-,3/2-,

5/2-)

Λc(1/2-,3/2-)

Σ

c

(1/2-,1/2- 3/2-,3/2-,

5/2-)

Σc(1/2+,3/2+

c(1/2+)

“Q” may isolate “qq”

q

q

q

Q

λ

q-q

Q

ρ

q-q

λ

mode

ρ

mode

G.S.

9/10-13, 2013

Charmed baryons

9Slide10

Decays

Ratio:

9/10-13, 2013

Charmed baryons

10

ρ

-mode

λ

-mode

ρ

-mode

バリオンは軽い中間子と重いバリオンに

λ

-mode

       重い      軽い     に崩壊Slide11

9/10-13, 2013

Charmed baryons11

1/2–

 1/2

+ E1 transition

λ

mode

Good

diquark

0+

l

λ = 1

3P0

diquark

0

= 1

ρ

mode

0

 0

+

is

forbidden

Good

diquark

0

+Slide12

9/10-13, 2013

Charmed baryons12

5/2–

 1/2

+ M2, E3 transition

λ

mode

3

S

1 diquark

1

+

= 1

3

P

2

diquark

2

= 1

ρ mode

2

 0

+

is

M2

Good

diquark

0

+

Both M2 E3Slide13

Role of a heavy quark

9/10-13, 2013Charmed baryons13

• Filter out 2

-body correlations

• Excitation spectru,

     λ-ρ modes, Good

vs

bad

diquark

• Decay pattern, selection rules• Diquark densitiesEstablish diquarks from QCD  Phenomena

Related Contents


Next Show more