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Elastic and diffractive scattering at the LHC (2018)
Journal Article
Khoze, V., Martin, A., & Ryskin, M. (2018). Elastic and diffractive scattering at the LHC. Physics Letters B, 784, 192-198. https://doi.org/10.1016/j.physletb.2018.07.054

Inspired by the new TOTEM data on elastic pp scattering at 13 TeV, we study the possibility to describe all the diffractive collider data (, , ) in a wide interval of energy (0.0625 to 13 TeV) in the framework of a two-channel eikonal model. We show... Read More about Elastic and diffractive scattering at the LHC.

Open charm production and low x gluons (2018)
Journal Article
de Oliveira, E., Martin, A., & Ryskin, M. (2018). Open charm production and low x gluons. Physical Review D, 97(7), Article 074021. https://doi.org/10.1103/physrevd.97.074021

We compare the rapidity, y, and the beam energy, ffiffi s p , behaviors of the cross section of the data for D meson production in the forward direction that were measured by the LHCb Collaboration. We describe the observed cross sections using NLO p... Read More about Open charm production and low x gluons.

The impact of LHC jet data on the MMHT PDF fit at NNLO (2018)
Journal Article
Harland-Lang, L., Martin, A., & Thorne, R. (2018). The impact of LHC jet data on the MMHT PDF fit at NNLO. The European Physical Journal C, 78(3), Article 248. https://doi.org/10.1140/epjc/s10052-018-5710-7

We investigate the impact of the high precision ATLAS and CMS 7 TeV measurements of inclusive jet production on the MMHT global PDF analysis at next-to-next-to-leading order (NNLO). This is made possible by the recent completion of the long-term proj... Read More about The impact of LHC jet data on the MMHT PDF fit at NNLO.

Multiple interactions and rapidity gap survival (2018)
Journal Article
Khoze, V., Martin, A., & Ryskin, M. (2018). Multiple interactions and rapidity gap survival. Journal of Physics G: Nuclear and Particle Physics, 45(5), Article 053002. https://doi.org/10.1088/1361-6471/aab1bf

Observations of rare processes containing large rapidity gaps at high energy colliders may be exceptionally informative. However the cross sections of these events are small in comparison with that for the inclusive processes since there is a large p... Read More about Multiple interactions and rapidity gap survival.

Black disk, maximal Odderon and unitarity (2018)
Journal Article
Khoze, V., Martin, A., & Ryskin, M. (2018). Black disk, maximal Odderon and unitarity. Physics Letters B, 780, 352-356. https://doi.org/10.1016/j.physletb.2018.03.025

We argue that the so-called maximal Odderon contribution breaks the ‘black disk’ behaviorof the asymp-totic amplitude, since the cross section of the events with Large Rapidity Gaps grows faster than the total cross section. That is the ‘maximal Odde... Read More about Black disk, maximal Odderon and unitarity.

Elastic proton-proton scattering at 13 TeV (2018)
Journal Article
Khoze, V., Martin, A., & Ryskin, M. (2018). Elastic proton-proton scattering at 13 TeV. Physical Review D, 97(3), Article 034019. https://doi.org/10.1103/physrevd.97.034019

The predictions of a model which was tuned in 2013 to describe the elastic and diffractive p p - and/or p ¯ p -data at collider energies up to 7 TeV are compared with the new 13 TeV TOTEM results. The possibility of the presence of an odd-signature O... Read More about Elastic proton-proton scattering at 13 TeV.

Total π + p cross section extracted from the leading neutron spectra at the LHC (2017)
Journal Article
Khoze, V., Martin, A., & Ryskin, M. (2017). Total π + p cross section extracted from the leading neutron spectra at the LHC. Physical Review D, 96(3), Article 034018. https://doi.org/10.1103/physrevd.96.034018

We use the very forward neutron energy spectra measured by the LHC forward experiment at 7 TeV to extract the πþp total cross section at center-of-mass energies in the range 2.3–3.5 TeV. To do this, we have to first isolate the π-exchange pole in for... Read More about Total π + p cross section extracted from the leading neutron spectra at the LHC.

MMHT PDFs: Updates and Outlook (2017)
Journal Article
Harland-Lang, L., Nathvani, R., Thorne, R., & Martin, A. (2017). MMHT PDFs: Updates and Outlook. Acta Physica Polonica B, 48(6), 1011-1024. https://doi.org/10.5506/aphyspolb.48.1011

We present the latest results of studies within the MMHT PDF framework. We discuss the impact of the most recent ATLAS 7 TeV jet data, demonstrating that while a good fit can be achieved for individual jet rapidity bins, it is not possible to achieve... Read More about MMHT PDFs: Updates and Outlook.

Optimal choice of factorization scales for the description of jet production at the LHC (2017)
Journal Article
Martin, A., & Ryskin, M. (2017). Optimal choice of factorization scales for the description of jet production at the LHC. The European Physical Journal C, 77(4), Article 218. https://doi.org/10.1140/epjc/s10052-017-4783-z

To obtain more precise parton distribution functions (PDFs) it is important to include data on inclusive high transverse energy jet production in the global parton analyses. These data have high statistics and the NNLO terms in the perturbative QCD (... Read More about Optimal choice of factorization scales for the description of jet production at the LHC.

Scale dependence of open cc¯ and bb¯ production in the low x region (2017)
Journal Article
Oliveira, E. D., Martin, A., & Ryskin, M. (2017). Scale dependence of open cc¯ and bb¯ production in the low x region. The European Physical Journal C, 77(3), Article 182. https://doi.org/10.1140/epjc/s10052-017-4750-8

The ‘optimal’ factorization scale μ0μ0 is calculated for open heavy quark production. We find that the optimal value is μF=μ0≃0.85p2T+m2Q−−−−−−−√μF=μ0≃0.85pT2+mQ2 ; a choice which allows us to resum the double-logarithmic, (αslnμ2Fln(1/x))n(αsln⁡μF2l... Read More about Scale dependence of open cc¯ and bb¯ production in the low x region.

Exclusive J=ψ production at the LHC in the kT factorisation approach (2017)
Journal Article
Jones, S., Martin, A., Ryskin, M., & Teubner, T. (2017). Exclusive J=ψ production at the LHC in the kT factorisation approach. Journal of Physics G: Nuclear and Particle Physics, 44(3), Article 03LT01. https://doi.org/10.1088/1361-6471/aa56ea

The recent LHCb data for exclusive J y peripheral production at 13 TeV motivate an improved ‘NLO’ analysis to estimate the gluon distribution at low x in which we re-calculate the rapidity gap survival factors and use a more precise expression for th... Read More about Exclusive J=ψ production at the LHC in the kT factorisation approach.

The exclusive J/ψ process at the LHC tamed to probe the low x gluon (2016)
Journal Article
Jones, S., Martin, A., Ryskin, M., & Teubner, T. (2016). The exclusive J/ψ process at the LHC tamed to probe the low x gluon. The European Physical Journal C, 76(11), Article 633. https://doi.org/10.1140/epjc/s10052-016-4493-y

The perturbative QCD expansion for J/ψ photoproduction appears to be unstable: the NLO correction is large (and of opposite sign) to the LO contribution. Moreover, the predictions are very sensitive to the choice of factorisation and renormalisation... Read More about The exclusive J/ψ process at the LHC tamed to probe the low x gluon.

Two scales in Bose–Einstein correlations (2016)
Journal Article
Khoze, V., Martin, A., Ryskin, M., & Schegelsky, V. (2016). Two scales in Bose–Einstein correlations. The European Physical Journal C, 76(4), Article 193. https://doi.org/10.1140/epjc/s10052-016-4055-3

We argue that the secondaries produced in high-energy hadron collisions are emitted by small-size sources distributed over a much larger area in impact parameter space occupied by the interaction amplitude. That is, Bose–Einstein correlation of two e... Read More about Two scales in Bose–Einstein correlations.

The impact of the final HERA combined data on PDFs obtained from a global fit (2016)
Journal Article
Harland-Lang, L., Martin, A., Motylinski, P., & Thorne, R. (2016). The impact of the final HERA combined data on PDFs obtained from a global fit. The European Physical Journal C, 76(4), Article 186. https://doi.org/10.1140/epjc/s10052-016-4020-1

We investigate the effect of including the HERA run I + II combined cross section data on the MMHT2014 PDFs. We present the fit quality within the context of the global fit and when only the HERA data are included. We examine the changes in both the... Read More about The impact of the final HERA combined data on PDFs obtained from a global fit.

Advantages of exclusiveγγproduction to probe high mass systems (2016)
Journal Article
Martin, A., & Ryskin, M. (2016). Advantages of exclusiveγγproduction to probe high mass systems. Journal of Physics G: Nuclear and Particle Physics, 43(4), Article 04LT02. https://doi.org/10.1088/0954-3899/43/4/04lt02

We recall that the exclusive production of high mass objects via γγ fusion at the LHC is not strongly suppressed in comparison with inclusive γγ fusion. Therefore it may be promising to study new objects, X, produced by the γγ subprocess in experimen... Read More about Advantages of exclusiveγγproduction to probe high mass systems.

Charm and beauty quark masses in the MMHT2014 global PDF analysis (2016)
Journal Article
Harland-Lang, L., Martin, A., Motylinski, P., & Thorne, R. (2016). Charm and beauty quark masses in the MMHT2014 global PDF analysis. The European Physical Journal C, 76(1), Article 10. https://doi.org/10.1140/epjc/s10052-015-3843-5

We investigate the variation in the MMHT2014 PDFs when we allow the heavy-quark masses mcmc and mbmb to vary away from their default values. We make PDF sets available in steps of Δmc=0.05 GeVΔmc=0.05 GeV and Δmb=0.25 GeVΔmb=0.25 GeV , and present th... Read More about Charm and beauty quark masses in the MMHT2014 global PDF analysis.

Inclusive prompt $$\chi _{c,b}(1^{++})$$ χ c , b ( 1 + + ) production at the LHC (2015)
Journal Article
Shuvaev, A., Khoze, V., Martin, A., & Ryskin, M. (2015). Inclusive prompt $$\chi _{c,b}(1^{++})$$ χ c , b ( 1 + + ) production at the LHC. The European Physical Journal C, 75(12), Article 616. https://doi.org/10.1140/epjc/s10052-015-3840-8

We study the prompt production of the χc(1+) and χb(1+) mesons at high energies. Unlike χ(0+,2+) production, χ(1+) mesons cannot be created at LO via the fusion of two on-mass-shell gluons, that is, gg→χc,b(1+) are not allowed. However, the available... Read More about Inclusive prompt $$\chi _{c,b}(1^{++})$$ χ c , b ( 1 + + ) production at the LHC.

Uncertainties on αSαS in the MMHT2014 global PDF analysis and implications for SM predictions (2015)
Journal Article
Harland-Lang, L., Martin, A., Motylinski, P., & Thorne, R. (2015). Uncertainties on αSαS in the MMHT2014 global PDF analysis and implications for SM predictions. The European Physical Journal C, 75(9), Article 435. https://doi.org/10.1140/epjc/s10052-015-3630-3

We investigate the uncertainty in the strong coupling αS(M2Z)αS(MZ2) when allowing it to be a free parameter in the recent MMHT global analyses of deep-inelastic and related hard scattering data that was undertaken to determine the parton distributio... Read More about Uncertainties on αSαS in the MMHT2014 global PDF analysis and implications for SM predictions.

Parton distributions in the LHC era: MMHT 2014 PDFs (2015)
Journal Article
Harland-Lang, L., Martin, A., Motylinski, P., & Thorne, R. (2015). Parton distributions in the LHC era: MMHT 2014 PDFs. The European Physical Journal C, 75(5), Article 204. https://doi.org/10.1140/epjc/s10052-015-3397-6

We present LO, NLO and NNLO sets of parton distribution functions (PDFs) of the proton determined from global analyses of the available hard scattering data. These MMHT2014 PDFs supersede the ‘MSTW2008’ parton sets, but they are obtained within the s... Read More about Parton distributions in the LHC era: MMHT 2014 PDFs.