We calculate the fiducial and differential <math><msup><mrow><mi>W</mi></mrow><mrow><mo>±</mo></mrow></msup><mo>/</mo><msup><mrow><mi>Z</mi></mrow><mrow><mn>0</mn></mrow></msup><mo>+</mo><mi>j</mi><mi>e</mi><mi>t</mi><mo>(</mo><mi>s</mi><mo>)</mo></math> production cross-sections in the presence of electroweak (EW) corrections through virtual loop contributions to the matrix elements (MEs) of the processes and real partonic cascade emissions. The calculations are carried out for proton-proton collisions at <math><msqrt><mrow><mi>s</mi></mrow></msqrt><mo>=</mo><mn>13</mn></math> TeV, using Herwig 7 general-purpose Monte-Carlo event generator with leading-order or next-to-leading-order MEs that are interfaced with different parton-shower configurations. The results are compared with precision experimental measurements from ATLAS collaboration and with similar predictions within the <math><msub><mrow><mi>k</mi></mrow><mrow><mi>t</mi></mrow></msub></math>-factorisation framework, providing a test for the validity of the newly-implemented QCD⊕QED⊕EW parton shower in Herwig 7. It is shown that the inclusion of EW radiations in the parton shower simulations improves Herwig 7's predictions in describing the experimental data. Additionally, the inclusion of parton shower-induced real EW emissions can take precedence over the incorporation of virtual EW corrections for the simulation of EW-sensitive events.

United States

China

Neda Darvishi

United Kingdom

M.R. Masouminia

Electroweak radiative corrections in precision LHC measurements of / +jets

The cross-section for the production of the Standard Model Higgs boson has been calculated using a mixture of LO and NLO partonic diagrams and the unintegrated parton distribution functions (<math><mi>U</mi><mi>P</mi><mi>D</mi><mi>F</mi></math>) of the Kimber–Martin–Ryskin (KMR) from the <math><msub><mrow><mi>k</mi></mrow><mrow><mi>t</mi></mrow></msub></math>-factorization framework. The <math><mi>U</mi><mi>P</mi><mi>D</mi><mi>F</mi></math> are prepared using the phenomenological libraries of Martin–Motylinski–Harland Lang–Thorne (<math><mi>M</mi><mi>M</mi><mi>H</mi><mi>T</mi><mn>2014</mn></math>). The results are compared against the existing experimental data from the CMS and the <math><mi>A</mi><mi>T</mi><mi>L</mi><mi>A</mi><mi>S</mi></math> collaborations and available <math><mi>p</mi><mi>Q</mi><mi>C</mi><mi>D</mi></math> calculation. It is shown that, while the present calculation is in agreement with the experimental data, it is comparable with the <math><mi>p</mi><mi>Q</mi><mi>C</mi><mi>D</mi></math> results. It is also concluded that the K-factor approximation is comparable with the semi-NLO <math><msub><mrow><mi>k</mi></mrow><mrow><mi>t</mi></mrow></msub></math>-factorization predictions.

Iran

M. Modarres

R. Aminzadeh Nik

H. Hosseinkhani

N. Olanj

Semi- production of Higgs bosons in the framework of -factorization Using Unintegrated Parton Distributions

In the present work, we intend to predict the production rates of the Higgs bosons in the simplest extension of the Standard Model (SM) by a neutral complex singlet (cSMCS). This model has an additional source of CP violation and provides strong enough first-order electroweak phase transition to generate the baryon asymmetry of universe (BAU). The scalar spectrum of the cSMCS includes three neutral Higgs particles with the lightest one considered to be the 125 GeV Higgs boson found at LHC. The SM-like Higgs boson comes mostly from the SM-like SU(2) doublet, with a small correction from the singlet. To predict the production rates of the Higgs bosons, we use a conventional effective LO QCD framework and the unintegrated parton distribution functions (UPDF) of Kimber–Martin–Ryskin (KMR). We first compute the SM Higgs production cross-section and compare the results to the existing theoretical calculations from different frameworks as well as the experimental data from the CMS and ATLAS collaborations. It is shown that our framework is capable of producing sound predictions for these high-energy QCD events in the SM. Afterwards we present our predictions for the Higgs boson production in the cSMCS.

Poland

N. Darvishi

A phenomenological study on the production of Higgs bosons in the cSMCS model at the LHC

Quite recently, two sets of new experimental data from the LHCb and the CMS Collaborations have been published, concerning the production of the Z0 vector boson in hadron–hadron collisions with the center-of-mass energy ECM=s=13TeV . On the other hand, in our recent work, we have conducted a set of semi- NLO calculations for the production of the electro-weak gauge vector bosons, utilizing the unintegrated parton distribution functions ( UPDF ) in the frameworks of Kimber–Martin–Ryskin ( KMR ) or Martin–Ryskin–Watt ( MRW ) and the kt -factorization formalism, concluding that the results of the KMR scheme are arguably better in describing the existing experimental data, coming from D 0, CDF , CMS and ATLAS Collaborations. In the present work, we intend to follow the same semi- NLO formalism and calculate the rate of the production of the Z0 vector boson, utilizing the UPDF of KMR within the dynamics of the recent data. It will be shown that our results are in good agreement with the new measurements of the LHCb and the CMS Collaborations.

KMR k t -factorization procedure for the description of the LHCb forward hadron–hadron Z 0 production at s=13TeV

The present work is devoted to study the high-energy QCD events, such as the di-jet productions from proton–proton inelastic collisions at the LHC in the forward-center and the forward-forward configurations. This provides us with much valuable case study, since such phenomena can provide a direct glimpse into the partonic behavior of a hadron in a dominant gluonic region. We use the unintegrated parton distribution functions ( UPDF ) in the kt -factorization framework. The UPDF of Kimber et al. ( KMR ) and Martin et al. ( MRW ) are generated in the leading order ( LO ) and next-to-leading order ( NLO ), using the Harland-Lang et al. ( MMHT2014 ) PDF libraries. While working in the forward-center and the forward-forward rapidity sectors, one can probe the parton densities at very low longitudinal momentum fractions ( x ). Such a model computation can provide simpler analytic description of data with respect to existing formalisms such as perturbative QCD . The differential cross-section calculations are performed at the center of mass energy of 7 TeV corresponding to CMS collaboration measurement. It is shown that the gluonic jet productions are dominant and a good description of data as well as other theoretical attempts (i.e. KS -linear, KS -nonlinear and rcBK ) is obtained. The uncertainty of the calculations is derived by manipulating the hard scale of the processes by a factor of two. This conclusion is achieved, due to the particular visualization of the angular ordering constraint ( AOC ), that is incorporated in the definition of these UPDF .

LHC production of forward-center and forward-forward di-jets in the k t -factorization and transverse dependent unintegrated parton distribution frameworks

We address the longitudinal proton structure function, FL(x,Q2) , from the kt -factorization formalism by using the unintegrated parton distribution functions (UPDF) which are generated through the KMR and MRW procedures. The LO UPDF of the KMR prescription is extracted, by taking into account the PDF of Martin et al, i.e., MSTW2008-LO and MRST99-NLO, and next the NLO UPDF of the MRW scheme is generated through the set of MSTW2008-NLO PDF as the input. The different aspects of FL(x,Q2) in the two approaches, as well as its perturbative and non-perturbative parts, are calculated. Then the comparison of FL(x,Q2) is made with the data given by the ZEUS and H1 collaborations. It is demonstrated that the extracted FL(x,Q2) , based on the UPDF of two schemes, are consistent with the experimental data, and to a good approximation they are independent of the input PDF. But the one developed from the KMR prescription has better agreement with the data with respect to that of MRW. As has been suggested, by lowering the factorization scale or the Bjorken variable in the related experiments it may be possible to analyze the present theoretical approaches more accurately.