Matrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading order
Abstract We discuss the role of matrix element corrections (MEC) to parton showers in the context of MC@NLO-type matchings for processes that feature unstable resonances, where MEC are liable to result in double-counting issues, and are thus generally not employed. By working with Pythia8, we show t...
| Main Authors: | , , |
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| Format: | Article |
| Language: | English |
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SpringerOpen
2023-10-01
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| Series: | European Physical Journal C: Particles and Fields |
| Online Access: | https://doi.org/10.1140/epjc/s10052-023-12154-x |
| _version_ | 1797247102250647552 |
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| author | Stefano Frixione Simone Amoroso Stephen Mrenna |
| author_facet | Stefano Frixione Simone Amoroso Stephen Mrenna |
| author_sort | Stefano Frixione |
| collection | DOAJ |
| description | Abstract We discuss the role of matrix element corrections (MEC) to parton showers in the context of MC@NLO-type matchings for processes that feature unstable resonances, where MEC are liable to result in double-counting issues, and are thus generally not employed. By working with Pythia8, we show that disabling all MEC is actually unnecessary in computations based on the narrow-width approximation, and we propose alternative MEC settings which, while still avoiding double counting, allow one to include hard-recoil effects in the simulations of resonance decays. We illustrate our findings by considering $$t\bar{t}$$ t t ¯ production at the LHC, and by comparing MadGraph5-aMC@NLO predictions with those of POWHEG-BOX and standalone Pythia8. |
| first_indexed | 2024-03-11T15:14:18Z |
| format | Article |
| id | doaj.art-edcc6c932f02400999853c6971b8ddc1 |
| institution | Directory Open Access Journal |
| issn | 1434-6052 |
| language | English |
| last_indexed | 2024-04-24T19:53:21Z |
| publishDate | 2023-10-01 |
| publisher | SpringerOpen |
| record_format | Article |
| series | European Physical Journal C: Particles and Fields |
| spelling | doaj.art-edcc6c932f02400999853c6971b8ddc12024-03-24T12:31:13ZengSpringerOpenEuropean Physical Journal C: Particles and Fields1434-60522023-10-01831011110.1140/epjc/s10052-023-12154-xMatrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading orderStefano Frixione0Simone Amoroso1Stephen Mrenna2INFN, Sezione di GenovaDeutsches Elektronen-Synchrotron DESYScientific Computing Division, Fermi National Accelerator LaboratoryAbstract We discuss the role of matrix element corrections (MEC) to parton showers in the context of MC@NLO-type matchings for processes that feature unstable resonances, where MEC are liable to result in double-counting issues, and are thus generally not employed. By working with Pythia8, we show that disabling all MEC is actually unnecessary in computations based on the narrow-width approximation, and we propose alternative MEC settings which, while still avoiding double counting, allow one to include hard-recoil effects in the simulations of resonance decays. We illustrate our findings by considering $$t\bar{t}$$ t t ¯ production at the LHC, and by comparing MadGraph5-aMC@NLO predictions with those of POWHEG-BOX and standalone Pythia8.https://doi.org/10.1140/epjc/s10052-023-12154-x |
| spellingShingle | Stefano Frixione Simone Amoroso Stephen Mrenna Matrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading order European Physical Journal C: Particles and Fields |
| title | Matrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading order |
| title_full | Matrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading order |
| title_fullStr | Matrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading order |
| title_full_unstemmed | Matrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading order |
| title_short | Matrix element corrections in the Pythia8 parton shower in the context of matched simulations at next-to-leading order |
| title_sort | matrix element corrections in the pythia8 parton shower in the context of matched simulations at next to leading order |
| url | https://doi.org/10.1140/epjc/s10052-023-12154-x |
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