Determination of the strong coupling constant $$\alpha _s \left( m_Z \right) $$ α s m Z from measurements of the total cross section for top–antitop-quark production
Abstract We present a determination of the strong coupling constant $$\alpha _s \left( m_Z \right) $$ α s m Z using inclusive top-quark pair production cross section measurements performed at the LHC and at the Tevatron. Following a procedure first applied by the CMS Collaboration, we extract indivi...
| Main Authors: | , , , |
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| Format: | Article |
| Language: | English |
| Published: |
SpringerOpen
2017-11-01
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| Series: | European Physical Journal C: Particles and Fields |
| Online Access: | http://link.springer.com/article/10.1140/epjc/s10052-017-5340-5 |
| Summary: | Abstract We present a determination of the strong coupling constant $$\alpha _s \left( m_Z \right) $$ α s m Z using inclusive top-quark pair production cross section measurements performed at the LHC and at the Tevatron. Following a procedure first applied by the CMS Collaboration, we extract individual values of $$\alpha _s \left( m_Z \right) $$ α s m Z from measurements by different experiments at several centre-of-mass energies, using QCD predictions complete in NNLO perturbation theory, supplemented with NNLL approximations to all orders, and suitable sets of parton distribution functions. The determinations are then combined using a likelihood-based approach, where special emphasis is put on a consistent treatment of theoretical uncertainties and of correlations between various sources of systematic uncertainties. Our final combined result is $$\alpha _s \left( m_Z \right) =0.1177^{+0.0034{}}_{-0.0036{}}$$ α s m Z = 0 . 1177 - 0.0036 + 0.0034 . |
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| ISSN: | 1434-6044 1434-6052 |