Structure of parton quasi-distributions and their moments
We discuss the structure of the parton quasi-distributions (quasi-PDFs) Q(y,P3) outside the “canonical” −1≤y≤1 support region of the usual parton distribution functions (PDFs). Writing the yn moments of Q(y,P3) in terms of the combined xn−2lk⊥2l-moments of the transverse momentum distribution (TMD)...
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| Format: | Article |
| Language: | English |
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Elsevier
2019-01-01
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| Series: | Physics Letters B |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0370269318308931 |
| _version_ | 1818565742875901952 |
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| author | A.V. Radyushkin |
| author_facet | A.V. Radyushkin |
| author_sort | A.V. Radyushkin |
| collection | DOAJ |
| description | We discuss the structure of the parton quasi-distributions (quasi-PDFs) Q(y,P3) outside the “canonical” −1≤y≤1 support region of the usual parton distribution functions (PDFs). Writing the yn moments of Q(y,P3) in terms of the combined xn−2lk⊥2l-moments of the transverse momentum distribution (TMD) F(x,k⊥2), we establish a connection between the large-|y| behavior of Q(y,P3) and large-k⊥2 behavior of F(x,k⊥2). In particular, we show that the 1/k⊥2 hard tail of TMDs in QCD results in a slowly decreasing ∼1/|y| behavior of quasi-PDFs for large |y| that produces infinite yn moments of Q(y,P3). We also relate the ∼1/|y| terms with the lnz32-singularities of the Ioffe-time pseudo-distributions M(ν,z32). Converting the operator product expansion for M(ν,z32) into a matching relation between the quasi-PDF Q(y,P3) and the light-cone PDF f(x,μ2), we demonstrate that there is no contradiction between the infinite values of the yn moments of Q(y,P3) and finite values of the xn moments of f(x,μ2). |
| first_indexed | 2024-12-14T01:44:58Z |
| format | Article |
| id | doaj.art-c6fe5a90b63a4e7490d64db5a5617b7e |
| institution | Directory Open Access Journal |
| issn | 0370-2693 |
| language | English |
| last_indexed | 2024-12-14T01:44:58Z |
| publishDate | 2019-01-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Physics Letters B |
| spelling | doaj.art-c6fe5a90b63a4e7490d64db5a5617b7e2022-12-21T23:21:35ZengElsevierPhysics Letters B0370-26932019-01-01788380387Structure of parton quasi-distributions and their momentsA.V. Radyushkin0Physics Department, Old Dominion University, Norfolk, VA 23529, USA; Thomas Jefferson National Accelerator Facility, Newport News, VA 23606, USA; Correspondence to: Thomas Jefferson National Accelerator Facility, Newport News, VA 23606, USA.We discuss the structure of the parton quasi-distributions (quasi-PDFs) Q(y,P3) outside the “canonical” −1≤y≤1 support region of the usual parton distribution functions (PDFs). Writing the yn moments of Q(y,P3) in terms of the combined xn−2lk⊥2l-moments of the transverse momentum distribution (TMD) F(x,k⊥2), we establish a connection between the large-|y| behavior of Q(y,P3) and large-k⊥2 behavior of F(x,k⊥2). In particular, we show that the 1/k⊥2 hard tail of TMDs in QCD results in a slowly decreasing ∼1/|y| behavior of quasi-PDFs for large |y| that produces infinite yn moments of Q(y,P3). We also relate the ∼1/|y| terms with the lnz32-singularities of the Ioffe-time pseudo-distributions M(ν,z32). Converting the operator product expansion for M(ν,z32) into a matching relation between the quasi-PDF Q(y,P3) and the light-cone PDF f(x,μ2), we demonstrate that there is no contradiction between the infinite values of the yn moments of Q(y,P3) and finite values of the xn moments of f(x,μ2).http://www.sciencedirect.com/science/article/pii/S0370269318308931 |
| spellingShingle | A.V. Radyushkin Structure of parton quasi-distributions and their moments Physics Letters B |
| title | Structure of parton quasi-distributions and their moments |
| title_full | Structure of parton quasi-distributions and their moments |
| title_fullStr | Structure of parton quasi-distributions and their moments |
| title_full_unstemmed | Structure of parton quasi-distributions and their moments |
| title_short | Structure of parton quasi-distributions and their moments |
| title_sort | structure of parton quasi distributions and their moments |
| url | http://www.sciencedirect.com/science/article/pii/S0370269318308931 |
| work_keys_str_mv | AT avradyushkin structureofpartonquasidistributionsandtheirmoments |