Download or read book Higgs Production in Association with a Top antitop Pair in the Standard Model Effective Field Theory at NLO in QCD written by and published by . This book was released on 2016 with total page 43 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present the results of the computation of the next-to-leading order QCD corrections to the production cross section of a Higgs boson in association with a top-antitop pair at the LHC, including the three relevant dimension-six operators (Ot[phi], O[phi]G, OtG) of the standard model effective field theory. These operators also contribute to the production of Higgs bosons in loop-induced processes at the LHC, such as inclusive Higgs, Hj and HH production, and modify the Higgs decay branching ratios for which we also provide predictions. We perform a detailed study of the cross sections and their uncertainties at the total as well as differential level and of the structure of the effective field theory at NLO including renormalisation group effects. Finally, we show how the combination of information coming from measurements of these production processes will allow to constrain the three operators at the current and future LHC runs. Finally, our results lead to a significant improvement of the accuracy and precision of the deviations expected from higher-dimensional operators in the SM in both the top-quark and the Higgs-boson sectors and provide a necessary ingredient for performing a global EFT fit to the LHC data at NLO accuracy.
Download or read book Higgs boson potential at colliders status and perspectives written by Biagio Di Micco and published by Roma TrE-Press. This book was released on 2020-12-18 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: Questo documento riassume lo stato attuale degli ricerche studi, teorici e sperimentali, sulla produzione di coppie di bosoni di Higgs, e sui vincoli, sia diretti che indiretti, al valore del termine di auto-interazione del bosone di Higgs, con l’intento di servire da referenza per i prossimi anni. Il documento discute lo stato degli studi teorici, includendo le più recenti stime della sezione di produzione di coppie di bosoni di Higgs, sviluppi sulle teorie di campo efficaci, e studi su specifici scenari di nuova fisica che possono contribuire alla produzione di due bosoni di Higgs. Sono presentati i più recenti risultati sperimentali sulle ricerche di coppie di bosoni di Higgs e sui limiti diretti e indiretti al termine di auto-interazione, ottenuti al Large Hadron Collider di Ginevra, con una panoramica delle tecniche sperimentali. Infine, sono discusse le capacità dei collisionatori futuri di determinare il termine di auto-interazione del bosone di Higgs. Questo lavoro è iniziato come raccolta di contributi della conferenza “Di-Higgs ai Colliders”, che ha avuto luogo a Fermilab dal 4 al 9 settembre 2018, ma gli argomenti discussi vanno al di là di quelli presentati alla conferenza, includendo ulteriori sviluppi.
Download or read book Precision Calculations in Effective Theories for Higgs Production written by Nicolas Deutschmann and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: After a general introduction, this manuscript presents two preliminary chapters, describing first the physics context and the mathematical techniques used in this thesis.We then present the work performed in this thesis. We start with extraction of the power-suppressed of the Yukawa coupling of the bottom quark in the Higgs Effective Field Theory (HEFT) by a two-loop matching calculation between the Standard Model and the HEFT. This correction was the missing piece to improve the prediction of the production cross section of a Higgs boson in association to a pair of bottom quarks.The two next chapters present different aspects of the NLO corrections to Higgs boson production through gluon fusion in the standard model effective field theory. We first present the evaluation of the virtual corrections to this process and use the known one-loop ultraviolet and infrared divergence structure to extract a two-loop counterterm that allowed us to renormalize the amplitude, which we then analytically continued to the physical regions.We then combine this result with the automatic calculation of the real emission corrections in the program Madgraph5_aMC@NLO. The results are presented for the total cross section and differential distributions and comment on the effect of radiative corrections on these predictions.
Download or read book Beyond Standard Model Collider Phenomenology of Higgs Physics and Supersymmetry written by Marc Christopher Thomas and published by Springer. This book was released on 2016-08-01 with total page 113 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis studies collider phenomenology of physics beyond the Standard Model at the Large Hadron Collider (LHC). It also explores in detail advanced topics related to Higgs boson and supersymmetry – one of the most exciting and well-motivated streams in particle physics. In particular, it finds a very large enhancement of multiple Higgs boson production in vector-boson scattering when Higgs couplings to gauge bosons differ from those predicted by the Standard Model. The thesis demonstrates that due to the loss of unitarity, the very large enhancement for triple Higgs boson production takes place. This is a truly novel finding. The thesis also studies the effects of supersymmetric partners of top and bottom quarks on the Higgs production and decay at the LHC, pointing for the first time to non-universal alterations for two main production processes of the Higgs boson at the LHC–vector boson fusion and gluon–gluon fusion. Continuing the exploration of Higgs boson and supersymmetry at the LHC, the thesis extends existing experimental analysis and shows that for a single decay channel the mass of the top quark superpartner below 175 GeV can be completely excluded, which in turn excludes electroweak baryogenesis in the Minimal Supersymmetric Model. This is a major new finding for the HEP community. This thesis is very clearly written and the introduction and conclusions are accessible to a wide spectrum of readers.
Download or read book Higgs pair Production Via Gluon Fusion at NLO QCD in the Standard Model and Beyond written by Jonathan Ronca and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book QCD Corrections to Higgs Pair Production in Bottom Quark Fusion written by and published by . This book was released on 2006 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: We present a complete next-to-leading order (NLO) calculation for the total cross section of inclusive Higgs pair production via bottom-quark fusion (b{bar b} → hh) at the CERN Large Hadron Collider (LHC) in the Standard Model. The NLO QCD corrections lead to less dependence on the renormalization scale ([mu]{sub R}) and the factorization scale ([mu]{sub F}) than the leading-order (LO) cross section, and they significantly increase the LO cross section. The rate for inclusive Higgs pair production is small in the Standard Model, but can be large in models with enhanced couplings of the b quark to the Higgs bosons.
Download or read book Full Mass Dependence in Higgs Boson Production in Association with Jets at the LHC and FCC written by and published by . This book was released on 2017 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first computation of Higgs production in association with three jets at NLO in QCD has recently been performed using the effective theory, where the top quark is treated as an infinitely heavy particle and integrated out. This approach is restricted to the regions in phase space where the typical scales are not larger than the top quark mass. Here we investigate this statement at a quantitative level by calculating the leading-order contributions to the production of a Standard Model Higgs boson in association with up to three jets taking full top-quark and bottom-quark mass dependence into account. We find that the transverse momentum of the hardest particle or jet plays a key role in the breakdown of the effective theory predictions, and that discrepancies can easily reach an order of magnitude for transverse momenta of about 1 TeV. The impact of bottom-quark loops is found to be visible in the small transverse momentum region, leading to corrections of up to 5 percent. Lastly, we further study the impact of mass corrections when VBF selection cuts are applied and when the center-of-mass energy is increased to 100 TeV.
Download or read book QCD and Collider Physics written by R. K. Ellis and published by Cambridge University Press. This book was released on 2003-12-04 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt: A detailed overview of the physics of high-energy colliders emphasising the role of QCD.
Download or read book Higgs Boson Production in Standard Model Effective Field Theory written by Agnieszka Janina Ilnicka and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Higgs Puzzle The What Can We Learn From Lep2 Lhc Nlc And Fmc Proceedings Of The 1996 Ringberg Workshop written by Bernd A Kniehl and published by World Scientific. This book was released on 1997-07-15 with total page 354 pages. Available in PDF, EPUB and Kindle. Book excerpt: Despite the great success of the standard model of electroweak and strong interactions to describe the phenomena observed in high energy physics experiments, the mechanism by which the elementary particles are endowed with their masses is yet to be unraveled. Does nature choose the Higgs mechanism of spontaneous symmetry breaking as predicted by the standard model, or do we need some alternative explanation? The purpose of the workshop is to capture new trends and ideas in this exciting area of fundamental physics, and to explore the potential of recent (LEPI), present (HERA, LEPII, SLC, Tevatron), and future (FMC, LHC, NLC) colliding-beam experiments to shed light on the Higgs puzzle.
Download or read book The Standard Model Higgs Boson written by Martin B. Einhorn and published by North Holland. This book was released on 1991 with total page 408 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume 8.
Download or read book Looking Inside Jets written by Simone Marzani and published by Springer. This book was released on 2019-05-11 with total page 205 pages. Available in PDF, EPUB and Kindle. Book excerpt: This concise primer reviews the latest developments in the field of jets. Jets are collinear sprays of hadrons produced in very high-energy collisions, e.g. at the LHC or at a future hadron collider. They are essential to and ubiquitous in experimental analyses, making their study crucial. At present LHC energies and beyond, massive particles around the electroweak scale are frequently produced with transverse momenta that are much larger than their mass, i.e., boosted. The decay products of such boosted massive objects tend to occupy only a relatively small and confined area of the detector and are observed as a single jet. Jets hence arise from many different sources and it is important to be able to distinguish the rare events with boosted resonances from the large backgrounds originating from Quantum Chromodynamics (QCD). This requires familiarity with the internal properties of jets, such as their different radiation patterns, a field broadly known as jet substructure. This set of notes begins by providing a phenomenological motivation, explaining why the study of jets and their substructure is of particular importance for the current and future program of the LHC, followed by a brief but insightful introduction to QCD and to hadron-collider phenomenology. The next section introduces jets as complex objects constructed from a sequential recombination algorithm. In this context some experimental aspects are also reviewed. Since jet substructure calculations are multi-scale problems that call for all-order treatments (resummations), the bases of such calculations are discussed for simple jet quantities. With these QCD and jet physics ingredients in hand, readers can then dig into jet substructure itself. Accordingly, these notes first highlight the main concepts behind substructure techniques and introduce a list of the main jet substructure tools that have been used over the past decade. Analytic calculations are then provided for several families of tools, the goal being to identify their key characteristics. In closing, the book provides an overview of LHC searches and measurements where jet substructure techniques are used, reviews the main take-home messages, and outlines future perspectives.
Download or read book Evidence for a Standard Model Higgs Boson Produced in Association with a Top Quark Pair and Decaying to Leptons written by Charles N. Mueller and published by . This book was released on 2017 with total page 169 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Searching for the Standard Model Higgs Boson Produced in Association with a Top quark Pair in PP Collisions at the LHC written by Wuming Luo and published by . This book was released on 2014 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Two loop Virtual QCD Corrections to Higgs Boson Pair Production in the Standard Model written by and published by . This book was released on 2016 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: Here, we compute the next-to-leading order virtual QCD corrections to Higgs-pair production via gluon fusion. We also present analytic results for the two-loop contributions to the spin-0 and spin-2 form factors in the amplitude. The reducible contributions, given by the double-triangle diagrams, are evaluated exactly while the two-loop irreducible diagrams are evaluated by an asymptotic expansion in heavy top-quark mass up to and including terms of O(1/m$8\atop{t}$). We estimate that mass effects can reduce the hadronic cross section by at most 10 %, assuming that the finite top-quark mass effects are of similar size in the entire range of partonic energies.
Download or read book Observation of the Standard Model Higgs Boson Produced in Association with a Pair of Top Quarks at sqrt s written by Johannes Donatus Mellenthin and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The top quark is the heaviest elementary particle in the Standard Model and has an expected Yukawa coupling to the Higgs boson of order unity. The value of this coupling is a key ingredient to unravel the nature of the observed Higgs boson. The most favourable production mode that has a direct sensitivity to this coupling is the production of a Higgs boson in association with a top-quark pair, $t\bar{t}H$. This process was observed based on the analysis of proton-proton collision data at $\sqrt{s} = 13 \, \text{TeV}$ recorded with the ATLAS experiment at the LHC. Using data corresponding to...
Download or read book Application of Quantum Field Theory to Phenomenology RADCOR 2002 written by Johannes Blümlein and published by . This book was released on 2003 with total page 498 pages. Available in PDF, EPUB and Kindle. Book excerpt:
