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Understanding the fundamental structure of matter requires an understanding of how quarks and gluons are assembled to form hadrons and of the structure of the protons which are the colliding particles at LHC. The arrangement of quarks and…

High Energy Physics - Phenomenology · Physics 2014-11-20 Laurent Schoeffel

The spatial distribution of charge and magnetization within the proton is encoded in the elastic form factors. These have been precisely measured in elastic electron scattering, and the combination of proton and neutron form factors allows…

Nuclear Experiment · Physics 2015-02-11 I. A. Qattan , J. Arrington , A. Alsaad

A surprisingly large asymmetry between the up and down sea quark distributions in the nucleon has been observed in recent deep inelastic scattering and Drell-Yan experiments. This result strongly suggests that the mesonic degrees of freedom…

Nuclear Experiment · Physics 2008-11-26 Gerald T. Garvey , Jen-Chieh Peng

The advantage and feasibility of using $W$-boson production to extract unique information on the flavor asymmetry of the $\bar u$ and $\bar d$ sea-quark distributions in the proton are examined. The $W^+$ and $W^-$ production cross section…

Nuclear Experiment · Physics 2009-09-21 Ruizhe Yang , Jen-Chieh Peng , Matthias Große-Perdekamp

We motivate a measurement of various ratios of $W$ and $Z$ cross sections at the Large Hadron Collider (LHC) at large values of the boson transverse momentum ($p_T\gtrsim M_{W,Z}$). We study the dependence of predictions for these…

High Energy Physics - Phenomenology · Physics 2014-02-10 Sarah Alam Malik , Graeme Watt

We examine the implications of the recent CDF measurement of the top-quark forward-backward asymmetry, focusing on a scenario with a new color octet vector boson at 1-3 TeV. We study several models, as well as a general effective field…

High Energy Physics - Phenomenology · Physics 2015-03-18 Yang Bai , JoAnne L. Hewett , Jared Kaplan , Thomas G. Rizzo

An analysis procedure is proposed to measure the antiquark distributions in the proton over the region 0.01 < x < 0.1. The procedure involves the measurement of high p_t asymmetric direct photon and jet final states in pp interactions. This…

High Energy Physics - Phenomenology · Physics 2009-10-30 R. G. Badalian , S. Heppelmann

We investigate the mechanical properties of the proton by extracting its flavor-decomposed gravitational form factors (GFFs) using Light-Cone QCD sum rules (LCSR). These form factors encode critical information about the internal dynamics…

High Energy Physics - Phenomenology · Physics 2025-08-12 Zeinab Dehghan , F. Almaksusi , K. Azizi

The dependence of the top-quark mass measurement in top-quark pair production on the parton distribution functions (PDF) is explored through differential mass distributions in $t\bar{t}$ and $t\bar{t}j$ production at the LHC and a future…

High Energy Physics - Phenomenology · Physics 2023-08-08 Jason Gombas , Reinhard Schwienhorst , Jarrett Fein , Sara Sawford

We present calculations of several pp scattering cross sections with potential applications at the LHC. Significantly large rates for momentum fraction, x, as low as 10^-7 are obtained, allowing for possible extraction of quark and gluon…

High Energy Physics - Phenomenology · Physics 2016-08-25 L. Alvero , J. C. Collins , M. Strikman , J. J. Whitmore

Motivated by recent measurements of the top quark forward-backward asymmetry at the Tevatron, we study how t-channel new physics can contribute to a large value. We concentrate on a theory with an abelian gauge boson possessing flavor…

High Energy Physics - Phenomenology · Physics 2010-04-06 Sunghoon Jung , Hitoshi Murayama , Aaron Pierce , James D. Wells

Measurements of the forward-backward asymmetry in neutral-current Drell-Yan di-lepton production have primarily been used for determinations of the weak mixing angle $\theta_W$. We observe that, unlike the case of Run-I of the Large Hadron…

High Energy Physics - Phenomenology · Physics 2019-03-19 Elena Accomando , Juri Fiaschi , Francesco Hautmann , Stefano Moretti

A measurement is presented of differential cross sections for $t$-channel single top quark and antiquark production in proton-proton collisions at a centre-of-mass energy of 13 TeV by the CMS experiment at the LHC. From a data set…

High Energy Physics - Experiment · Physics 2020-05-08 CMS Collaboration

Production of electroweak bosons, heavy quarks and jets in proton-proton collisions probe different aspects of QCD and are sensitive to the details of proton structure, expressed by parton distribution functions (PDFs). Precise measurements…

High Energy Physics - Experiment · Physics 2019-08-13 Saranya Ghosh

The parton-level top quark (t) forward-backward asymmetry and the anomalous chromoelectric ($\hat{d}_\mathrm{t}$) and chromomagnetic ($\hat{\mu}_\mathrm{t}$) moments have been measured using LHC pp collisions at a center-of-mass energy of…

High Energy Physics - Experiment · Physics 2020-07-03 CMS Collaboration

We consider new physics explanations of the anomaly in the top quark forward-backward asymmetry measured at the Tevatron, in the context of flavor conserving models. The recently measured LHC dijet distributions strongly constrain many…

High Energy Physics - Phenomenology · Physics 2015-05-27 Zoltan Ligeti , Gustavo Marques Tavares , Martin Schmaltz

The forward-backward asymmetry $A_{FB}$ in top quark pair production, measured at the Tevatron, is probably related to the contribution of new particles. The Tevatron result is more than a $2\sigma$ deviation from the standard model…

High Energy Physics - Phenomenology · Physics 2011-03-21 E. Ramirez Barreto , Y. A. Coutinho , J. Sá Borges

Forward-backward asymmetry $A_{\rm FB}$ is an essential observable to study the nature of coupling in the standard model and physics beyond the standard model, as shown at LEP and Tevatron. As a proton-proton collider, the LHC does not have…

High Energy Physics - Phenomenology · Physics 2011-02-01 You-kai Wang , Bo Xiao , Shou-hua Zhu

A sizeable difference in the differential production cross section of top and antitop quarks, respectively, is predicted for hadronically produced heavy quarks. It is of order $\alpha_s$ and arises from the interference between charge odd…

High Energy Physics - Phenomenology · Physics 2008-11-26 J. H. Kühn , G. Rodrigo

Based on quantum fluctuations in momentum and of the proton into meson-baryon pairs, we develop a physical model for the non-perturbative x-shape of parton density functions in the proton. The model describes the proton structure function…

High Energy Physics - Phenomenology · Physics 2007-05-23 Johan Alwall , Gunnar Ingelman