Saved in:
| Main Authors: | , , |
|---|---|
| Format: | Preprint |
| Published: |
2026
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2602.24187 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866908872923414528 |
|---|---|
| author | Shi, Chao Lu, Liming Jia, Wenbao |
| author_facet | Shi, Chao Lu, Liming Jia, Wenbao |
| contents | We compute the twist-2 unpolarized quark parton distribution functions (PDFs) of the pion and the $ρ$ meson within the Dyson-Schwinger equations (DSEs) framework using the rainbow-ladder (RL) truncation. A new DSE for the spin-1 hadron's quark-quark correlation matrix is derived, from which the PDFs can be extracted. For the $ρ$ meson, we obtain for the first time within RL-DSEs the unpolarized PDFs corresponding to different helicity states. A pronounced difference is observed between the $|Λ|=1$ and $Λ=0$ cases, where $Λ$ denotes the meson helicity, leading to a nonvanishing and numerically sizable tensor-polarized PDF $f_{1LL}(x)$. We further compare these results with those obtained under a leading Fock-state ($|q\bar{q}\rangle$) truncation and find substantial deviations. This comparison demonstrates that the present RL-DSEs framework incorporates higher Fock-state contributions associated with gluonic degrees of freedom, which has a significant impact on the quark distributions. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2602_24187 |
| institution | arXiv |
| publishDate | 2026 |
| record_format | arxiv |
| spellingShingle | Pion and $ρ$ meson's unpolarized quark distribution functions from $q\bar{q}$ and all Fock-states within Dyson--Schwinger equations Shi, Chao Lu, Liming Jia, Wenbao High Energy Physics - Phenomenology We compute the twist-2 unpolarized quark parton distribution functions (PDFs) of the pion and the $ρ$ meson within the Dyson-Schwinger equations (DSEs) framework using the rainbow-ladder (RL) truncation. A new DSE for the spin-1 hadron's quark-quark correlation matrix is derived, from which the PDFs can be extracted. For the $ρ$ meson, we obtain for the first time within RL-DSEs the unpolarized PDFs corresponding to different helicity states. A pronounced difference is observed between the $|Λ|=1$ and $Λ=0$ cases, where $Λ$ denotes the meson helicity, leading to a nonvanishing and numerically sizable tensor-polarized PDF $f_{1LL}(x)$. We further compare these results with those obtained under a leading Fock-state ($|q\bar{q}\rangle$) truncation and find substantial deviations. This comparison demonstrates that the present RL-DSEs framework incorporates higher Fock-state contributions associated with gluonic degrees of freedom, which has a significant impact on the quark distributions. |
| title | Pion and $ρ$ meson's unpolarized quark distribution functions from $q\bar{q}$ and all Fock-states within Dyson--Schwinger equations |
| topic | High Energy Physics - Phenomenology |
| url | https://arxiv.org/abs/2602.24187 |