Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all angles
Abstract We compute the fermionic contributions to the cusp anomalous dimension in QCD at four loops as an expansion for small cusp angle. As a byproduct we also obtain the respective terms of the four-loop HQET wave function anomalous dimension. Our new results at small angles provide stringent tes...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2019-05-01
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| Series: | Journal of High Energy Physics |
| Subjects: | |
| Online Access: | http://link.springer.com/article/10.1007/JHEP05(2019)186 |
| _version_ | 1819065004999049216 |
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| author | Robin Brüser Andrey Grozin Johannes M. Henn Maximilian Stahlhofen |
| author_facet | Robin Brüser Andrey Grozin Johannes M. Henn Maximilian Stahlhofen |
| author_sort | Robin Brüser |
| collection | DOAJ |
| description | Abstract We compute the fermionic contributions to the cusp anomalous dimension in QCD at four loops as an expansion for small cusp angle. As a byproduct we also obtain the respective terms of the four-loop HQET wave function anomalous dimension. Our new results at small angles provide stringent tests of a recent conjecture for the exact angle dependence of the matter terms in the four-loop cusp anomalous dimension. We find that the conjecture does not hold for two of the seven fermionic color structures, but passes all tests for the remaining terms. This provides strong support for the validity of the corresponding conjectured expressions with full angle dependence. Taking the limit of large Minkowskian angle, we extract novel analytic results for certain terms of the light-like cusp anomalous dimension. They agree with the known numerical results. Finally, we study the anti-parallel lines limit of the cusp anomalous dimension. In a conformal theory, the latter is proportional to the static quark-antiquark potential. We use the new four-loop results to determine parts of the conformal anomaly term. |
| first_indexed | 2024-12-21T15:39:35Z |
| format | Article |
| id | doaj.art-5305d96f001743be819062b4ba5f1680 |
| institution | Directory Open Access Journal |
| issn | 1029-8479 |
| language | English |
| last_indexed | 2024-12-21T15:39:35Z |
| publishDate | 2019-05-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | Journal of High Energy Physics |
| spelling | doaj.art-5305d96f001743be819062b4ba5f16802022-12-21T18:58:33ZengSpringerOpenJournal of High Energy Physics1029-84792019-05-012019512910.1007/JHEP05(2019)186Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all anglesRobin Brüser0Andrey Grozin1Johannes M. Henn2Maximilian Stahlhofen3PRISMA Cluster of Excellence, Johannes Gutenberg UniversityPRISMA Cluster of Excellence, Johannes Gutenberg UniversityMax-Planck-Institut für Physik, Werner-Heisenberg-InstitutPRISMA Cluster of Excellence, Johannes Gutenberg UniversityAbstract We compute the fermionic contributions to the cusp anomalous dimension in QCD at four loops as an expansion for small cusp angle. As a byproduct we also obtain the respective terms of the four-loop HQET wave function anomalous dimension. Our new results at small angles provide stringent tests of a recent conjecture for the exact angle dependence of the matter terms in the four-loop cusp anomalous dimension. We find that the conjecture does not hold for two of the seven fermionic color structures, but passes all tests for the remaining terms. This provides strong support for the validity of the corresponding conjectured expressions with full angle dependence. Taking the limit of large Minkowskian angle, we extract novel analytic results for certain terms of the light-like cusp anomalous dimension. They agree with the known numerical results. Finally, we study the anti-parallel lines limit of the cusp anomalous dimension. In a conformal theory, the latter is proportional to the static quark-antiquark potential. We use the new four-loop results to determine parts of the conformal anomaly term.http://link.springer.com/article/10.1007/JHEP05(2019)186Effective Field TheoriesPerturbative QCDScattering AmplitudesWilson, ’t Hooft and Polyakov loops |
| spellingShingle | Robin Brüser Andrey Grozin Johannes M. Henn Maximilian Stahlhofen Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all angles Journal of High Energy Physics Effective Field Theories Perturbative QCD Scattering Amplitudes Wilson, ’t Hooft and Polyakov loops |
| title | Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all angles |
| title_full | Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all angles |
| title_fullStr | Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all angles |
| title_full_unstemmed | Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all angles |
| title_short | Matter dependence of the four-loop QCD cusp anomalous dimension: from small angles to all angles |
| title_sort | matter dependence of the four loop qcd cusp anomalous dimension from small angles to all angles |
| topic | Effective Field Theories Perturbative QCD Scattering Amplitudes Wilson, ’t Hooft and Polyakov loops |
| url | http://link.springer.com/article/10.1007/JHEP05(2019)186 |
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