How can the results on N structure affect the exploration of the - - PowerPoint PPT Presentation

How can the results on N∗ structure affect the exploration of the ground state nucleon and meson structure, and vice versa?

Strong QCD from Hadron Structure Experiments 2019 Jefferson Lab, USA, 5-9 November 2019

Exploration of the ground state nucleon and meson structure 1/5

Non-perturbative QCD: Process-independent effective-charge and quark mass generation

• D. Binosi et al., Phys. Rev. D96 (2017) 054026.
• A. Deur et al., Prog. Part. Nucl. Phys. 90 (2016) 1-74.

/ () () / /

• []

()/ M.S. Bhagwat et al., Phys.Rev. C68 (2003) 015203

1 2 3 p [GeV] 0.1 0.2 0.3 0.4 M(p) [GeV]

m = 0 (Chiral limit) m = 30 MeV m = 70 MeV

effect of gluon cloud Rapid acquisition of mass is

10 years of gauge sector studies confirming 20 years of quark dynamics studies !

Exploration of the ground state nucleon and meson structure 2/5

Consequences on the pion

Form Factor PDF

0.0 0.2 0.4 0.6 0.8 1.0 0.0 0.2 0.4 x xpπ (x;ζ5)

A.C. Aguilar et al., Eur. Phys. J. A 55 (2019) 190

Exploration of the ground state nucleon and meson structure 3/5

The Baryon case

☞ EM form Factors of the proton and neutron:

see J. Segovia talk and J. Segovia et al., Few Body Syst. 55 (2014) 1185-1222

• 1

2 3 4 5 6 7 8 9 10 0.0 0.5 1.0 Q

2 GeV 2

ΜpGE

pGM p QCD-kindred CI-model

• 2

4 6 8 10 12 0.0 0.2 0.4 0.6 Q

2 GeV 2

ΜnGE

n GM n QCD-kindred CI-model

The existence and location of a zero crossing is a consequence of the underlying dynamics of QCD.

Exploration of the ground state nucleon and meson structure 4/5

From ground to excited states

☞ Transition FFs of the ∆

• Y. Lu et al., Phys.Rev. D100 (2019) no.3, 034001

☞ Transition FFs of the Roper resonance.

• C. Chen et al., Phys. Rev. D99 (2019) 034013
• ● ●
• 2

4 6 8 10 12 0.1 0.2 0.3 x=Q2/mN

2

• x F1,n

*

& x F1,p

*

Roper+

• Roper0

☞ Nucleon and Roper PDAs:

• C. Mezrag et al., Phys. Lett. B783 (2018) 263

0.2 0.4 0.6 0.8 0.2 0.4 0.6 0.8 0.2 0.4 0.6 0.8

ux2 ux1 dx3

0.2 0.4 0.6 0.8 0.2 0.4 0.6 0.8 0.2 0.4 0.6 0.8

ux2 ux1 dx3 3 1 1 3 5

Exploration of the ground state nucleon and meson structure 5/5