All Outputs (28)

Top tree amplitudes for higher order calculations (2023)
Journal Article
Campbell, J. M., & Ellis, R. K. (2023). Top tree amplitudes for higher order calculations. Journal of High Energy Physics, 2023(10), Article 125. https://doi.org/10.1007/jhep10%282023%29125

We present compact analytic results for tree-level amplitudes containing a tt¯ pair accompanied by up to four massless partons, tt¯gg, tt¯ggg, tt¯gggg, tt¯qq¯, tt¯qq¯g, tt¯qq¯gg and tt¯qq¯q′q¯′. The results, obtained using BCFW on-shell recursion, ar... Read More about Top tree amplitudes for higher order calculations.

Jet-veto resummation at N3LLp + NNLO in boson production processes (2023)
Journal Article
Campbell, J. M., Ellis, R. K., Neumann, T., & Seth, S. (2023). Jet-veto resummation at N3LLp + NNLO in boson production processes. Journal of High Energy Physics, 2023(4), Article 106. https://doi.org/10.1007/jhep04%282023%29106

Vetoing energetic jet activity is a crucial tool for suppressing backgrounds and enabling new physics searches at the LHC, but the introduction of a veto scale can introduce large logarithms that may need to be resummed. We present an implementation... Read More about Jet-veto resummation at N3LLp + NNLO in boson production processes.

Transverse momentum resummation at N3LL+NNLO for diboson processes (2023)
Journal Article
Campbell, J. M., Ellis, R. K., Neumann, T., & Seth, S. (2023). Transverse momentum resummation at N3LL+NNLO for diboson processes. Journal of High Energy Physics, 2023(3), Article 80. https://doi.org/10.1007/jhep03%282023%29080

Diboson processes are one of the most accessible and stringent probes of the electroweak gauge structure of the Standard Model at the LHC. They will be probed at the percent level at the high-luminosity LHC, challenging current theory predictions. We... Read More about Transverse momentum resummation at N3LL+NNLO for diboson processes.

Vector boson pair production at one loop: analytic results for the process $$ \mathrm{q}\overline{\mathrm{q}}\ell \overline{\ell}{\ell}^{\prime }{\overline{\ell}}^{\prime}\mathrm{g} $$ (2022)
Journal Article
Campbell, J. M., De Laurentis, G., & Ellis, R. K. (2022). Vector boson pair production at one loop: analytic results for the process $$ \mathrm{q}\overline{\mathrm{q}}\ell \overline{\ell}{\ell}^{\prime }{\overline{\ell}}^{\prime}\mathrm{g} $$. Journal of High Energy Physics, 2022(7), Article 96. https://doi.org/10.1007/jhep07%282022%29096

We present compact analytic results for the one-loop amplitude for the process 0 → qq¯¯ℓℓ¯ℓ′ℓ¯′g, relevant for both the production of a pair of Z and W-bosons in association with a jet. We focus on the gauge-invariant contribution mediated by a loop... Read More about Vector boson pair production at one loop: analytic results for the process $$ \mathrm{q}\overline{\mathrm{q}}\ell \overline{\ell}{\ell}^{\prime }{\overline{\ell}}^{\prime}\mathrm{g} $$.

Non-local slicing approaches for NNLO QCD in MCFM (2022)
Journal Article
Campbell, J. M., Ellis, R. K., & Seth, S. (2022). Non-local slicing approaches for NNLO QCD in MCFM. Journal of High Energy Physics, 2022(6), Article 2. https://doi.org/10.1007/jhep06%282022%29002

We present the implementation of several processes at Next-to-Next-to Leading Order (NNLO) accuracy in QCD in the parton-level Monte Carlo program MCFM. The processes treated are pp → H, W±, Z, W±H, ZH, W±γ, Zγ and γγ and, for the first time in the c... Read More about Non-local slicing approaches for NNLO QCD in MCFM.

The pp → W(→ lν) + γ process at next-to-next-to-leading order (2021)
Journal Article
Campbell, J. M., De Laurentis, G., Ellis, R. K., & Seth, S. (2021). The pp → W(→ lν) + γ process at next-to-next-to-leading order. Journal of High Energy Physics, 2021(7), https://doi.org/10.1007/jhep07%282021%29079

We present details of the calculation of the pp → W(→ lν)γ process at next-to-next-to-leading order in QCD, calculated using the jettiness slicing method. The calculation is based entirely on analytic amplitudes. Because of the radiation zero, the NL... Read More about The pp → W(→ lν) + γ process at next-to-next-to-leading order.

Analytic results for scalar-mediated Higgs boson production in association with two jets (2021)
Journal Article
Budge, L., Campbell, J. M., Ellis, R. K., & Seth, S. (2021). Analytic results for scalar-mediated Higgs boson production in association with two jets. Journal of Physics G: Nuclear and Particle Physics, 48(8), Article 085006. https://doi.org/10.1088/1361-6471/abf7d6

We present compact analytic formulae for all one-loop amplitudes representing the production of a Higgs boson in association with two jets, mediated by a colour triplet scalar particle. Many of the integral coefficients present for scalar mediators a... Read More about Analytic results for scalar-mediated Higgs boson production in association with two jets.

The one-loop amplitudes for Higgs + 4 partons with full mass effects (2020)
Journal Article
Budge, L., Campbell, J. M., De Laurentis, G., Ellis, R. K., & Seth, S. (2020). The one-loop amplitudes for Higgs + 4 partons with full mass effects. Journal of High Energy Physics, 2020(5), Article 79. https://doi.org/10.1007/jhep05%282020%29079

We present compact analytic formulae for the one-loop amplitudes for Higgs + 4 parton scattering, 0 → ggggh, 0 → qqggh ¯ and 0 → qq¯ q¯ 0 q 0h, mediated by a loop of massive coloured quarks. We exploit the correspondence with a theory in which a mass... Read More about The one-loop amplitudes for Higgs + 4 partons with full mass effects.

Higgs Boson studies at future particle colliders (2020)
Journal Article
de Blas, J., Cepeda, M., D’Hondt, J., Ellis, R., Grojean, C., Heinemann, B., …Verkerke, W. (2020). Higgs Boson studies at future particle colliders. Journal of High Energy Physics, 2020(1), Article 139. https://doi.org/10.1007/jhep01%282020%29139

This document aims to provide an assessment of the potential of future colliding beam facilities to perform Higgs boson studies. The analysis builds on the submissions made by the proponents of future colliders to the European Strategy Update process... Read More about Higgs Boson studies at future particle colliders.

H + 1 jet production revisited (2019)
Journal Article
Campbell, J. M., Ellis, R. K., & Seth, S. (2019). H + 1 jet production revisited. Journal of High Energy Physics, 2019(10), Article 136. https://doi.org/10.1007/jhep10%282019%29136

We revisit the next-to-next-to-leading order (NNLO) calculation of the Higgs boson+1 jet production process, calculated in the mt → ∞ effective field theory. We perform a detailed comparison of the result calculated using the jettiness slicing method... Read More about H + 1 jet production revisited.

On Higgs boson plus gluon amplitudes at one loop (2018)
Journal Article
Ellis, R. K., & Seth, S. (2018). On Higgs boson plus gluon amplitudes at one loop. Journal of High Energy Physics, 2018(11), Article 006. https://doi.org/10.1007/jhep11%282018%29006

We present analytic results for one-loop Higgs boson + n-gluon amplitudes for n ≤ 5 in the full theory including all dependence on the (top) quark mass. In this paper we consider only the case where the gluons all have the same helicity. The amplitud... Read More about On Higgs boson plus gluon amplitudes at one loop.

The NNLO QCD soft function for 1-jettiness (2018)
Journal Article
Campbell, J. M., Ellis, R. K., Mondini, R., & Williams, C. (2018). The NNLO QCD soft function for 1-jettiness. The European Physical Journal C, 78(3), Article 234. https://doi.org/10.1140/epjc/s10052-018-5732-1

We calculate the soft function for the global event variable 1-jettiness at next-to-next-to-leading order (NNLO) in QCD. We focus specifically on the non-Abelian contribution, which, unlike the Abelian part, is not determined by the next-to-leading o... Read More about The NNLO QCD soft function for 1-jettiness.

Driving missing data at the LHC: NNLO predictions for the ratio of γ + j and Z + j (2017)
Journal Article
Campbell, J. M., Ellis, R. K., & Williams, C. (2017). Driving missing data at the LHC: NNLO predictions for the ratio of γ + j and Z + j. Physical Review D, 96(1), Article 014037. https://doi.org/10.1103/physrevd.96.014037

In this paper, we present a calculation of the γ+j process at next-to-next-to-leading order (NNLO) in QCD and compare the resulting predictions to 8 TeV CMS data. We find good agreement with the shape of the photon pT spectrum, particularly after the... Read More about Driving missing data at the LHC: NNLO predictions for the ratio of γ + j and Z + j.

Direct Photon Production at Next-to–Next-to-Leading Order (2017)
Journal Article
Campbell, J. M., Ellis, R. K., & Williams, C. (2017). Direct Photon Production at Next-to–Next-to-Leading Order. Physical Review Letters, 118(22), Article 222001. https://doi.org/10.1103/physrevlett.118.222001

We present the first calculation of direct photon production at next-to-next-to-leading order (NNLO) accuracy in QCD. For this process, although the final-state cuts mandate only the presence of a single electroweak boson, the underlying kinematics r... Read More about Direct Photon Production at Next-to–Next-to-Leading Order.

Top-quark loop corrections in Z+jet and Z + 2 jet production (2017)
Journal Article
Campbell, J. M., & Ellis, R. K. (2017). Top-quark loop corrections in Z+jet and Z + 2 jet production. Journal of High Energy Physics, 2017(01), Article 020. https://doi.org/10.1007/jhep01%282017%29020

The sophistication of current predictions for Z+jet production at hadron colliders necessitates a re-evaluation of any approximations inherent in the theoretical calculations. In this paper we address one such issue, the inclusion of mass effects in... Read More about Top-quark loop corrections in Z+jet and Z + 2 jet production.

Color-singlet production at NNLO in MCFM (2016)
Journal Article
Boughezal, R., Campbell, J. M., Ellis, R. K., Focke, C., Giele, W., Liu, X., …Williams, C. (2017). Color-singlet production at NNLO in MCFM. The European Physical Journal C, 77(1), Article 7. https://doi.org/10.1140/epjc/s10052-016-4558-y

We present the implementation of several color-singlet final-state processes at Next-to-Next-to Leading Order (NNLO) accuracy in QCD to the publicly available parton-level Monte Carlo program MCFM. Specifically we discuss the processes pp→Hpp→H , pp→... Read More about Color-singlet production at NNLO in MCFM.

QCDLoop: A comprehensive framework for one-loop scalar integrals (2016)
Journal Article
Carrazza, S., Ellis, R., & Zanderighi, G. (2016). QCDLoop: A comprehensive framework for one-loop scalar integrals. Computer Physics Communications, 209, 134-143. https://doi.org/10.1016/j.cpc.2016.07.033

We present a new release of the QCDLoop library based on a modern object-oriented framework. We discuss the available new features such as the extension to the complex masses, the possibility to perform computations in double and quadruple precision... Read More about QCDLoop: A comprehensive framework for one-loop scalar integrals.

Two loop correction to interference in gg → ZZ (2016)
Journal Article
Campbell, J., Ellis, R., Czakon, M., & Kirchner, S. (2016). Two loop correction to interference in gg → ZZ. Journal of High Energy Physics, 2016(8), Article 11. https://doi.org/10.1007/jhep08%282016%29011

We present results for the production of a pair of on-shell Z bosons via gluon-gluon fusion. This process occurs both through the production and decay of the Higgs boson, and through continuum production where the Z boson couples to a loop of massles... Read More about Two loop correction to interference in gg → ZZ.

Predictions for diphoton production at the LHC through NNLO in QCD (2016)
Journal Article
Campbell, J., Ellis, R., Li, Y., & Williams, C. (2016). Predictions for diphoton production at the LHC through NNLO in QCD. Journal of High Energy Physics, 2016(7), Article 148. https://doi.org/10.1007/jhep07%282016%29148

In this paper we present a next-to-next-to-leading order (NNLO) calculation of the process pp → γγ that we have implemented into the parton level Monte Carlo code MCFM. We do not find agreement with the previous calculation of this process in the lit... Read More about Predictions for diphoton production at the LHC through NNLO in QCD.

Associated production of a Higgs boson at NNLO (2016)
Journal Article
Campbell, J. M., Ellis, R. K., & Williams, C. (2016). Associated production of a Higgs boson at NNLO. Journal of High Energy Physics, 2016(06), Article 179. https://doi.org/10.1007/jhep06%282016%29179

In this paper we present a Next-to-Next-to Leading Order (NNLO) calculation of the production of a Higgs boson in association with a massive vector boson. We include the decays of the unstable Higgs and vector bosons, resulting in a fully flexible pa... Read More about Associated production of a Higgs boson at NNLO.