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Author Alvarez, M.; Cantero, J.; Czakon, M.; Llorente, J.; Mitov, A.; Poncelet, R.
Title NNLO QCD corrections to event shapes at the LHC Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 03 Issue 3 Pages 129 - 24pp
Keywords (down) Higher-Order Perturbative Calculations; Specific QCD Phenomenology
Abstract In this work we perform the first ever calculation of jet event shapes at hadron colliders at next-to-next-to leading order (NNLO) in QCD. The inclusion of higher order corrections removes the shape difference observed between data and next-to-leading order predictions. The theory uncertainty at NNLO is comparable to, or slightly larger than, existing measurements. Except for narrow kinematical ranges where all-order resummation becomes important, the NNLO predictions for the event shapes considered in the present work are reliable. As a prime application of the results derived in this work we provide a detailed investigation of the prospects for the precision determination of the strong coupling constant and its running through TeV scales from LHC data.
Address [Czakon, Michal] Rhein Westfal TH Aachen, Inst Theoret Teilchenphys & Kosmol, D-52056 Aachen, Germany, Email: manuel.alvarez.estevez@cern.ch;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000992064600003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5560
Permanent link to this record
 

 
Author Kittel, O.; Pilaftsis, A.
Title CP violation in correlated production and decay of unstable particles Type Journal Article
Year 2012 Publication Nuclear Physics B Abbreviated Journal Nucl. Phys. B
Volume 856 Issue 3 Pages 682-697
Keywords (down) EPR correlation; Resonant CP violation; Collider phenomenology
Abstract We study resonant CP-violating Einstein-Podolsky-Rosen correlations that may take place in the production and decay of unstable scalar particles at high-energy colliders. We show that as a consequence of unitarity and CPT invariance of the S-matrix, in 2 -> 2 scatterings mediated by mixed scalar particles, at least three linearly independent decay matrices associated with the unstable scalar states are needed to obtain non-zero CP-odd observables that are also odd under C-conjugation. Instead, for the correlated production and decay of two unstable particle systems in 2 -> 4 processes, we find that only two independent decay matrices are sufficient to induce a net non-vanishing CP-violating phenomenon. As an application of this theorem, we present numerical estimates of CP asymmetries for the correlated production and decay of supersymmetric scalar top anti-top pairs at the LHC, and demonstrate that these could reach values of order one. As a byproduct of our analysis, we develop a novel spinorial trace technique, which enables us to efficiently evaluate lengthy expressions of squared amplitudes describing the resonant scalar transitions.
Address [Kittel, Olaf] Univ Granada, Dept Fis Teor & Cosmos, E-18071 Granada, Spain, Email: kittel@th.physik.uni-bonn.de
Corporate Author Thesis
Publisher Elsevier Science Bv Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0550-3213 ISBN Medium
Area Expedition Conference
Notes WOS:000300028200004 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 892
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Author Rinaldi, M.; Scopetta, S.; Traini, M.; Vento, V.
Title Correlations in double parton distributions: perturbative and non-perturbative effects Type Journal Article
Year 2016 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 10 Issue 10 Pages 063 - 36pp
Keywords (down) Deep Inelastic Scattering (Phenomenology); Phenomenological Models
Abstract The correct description of Double Parton Scattering (DPS), which represents a background in several channels for the search of new Physics at the LHC, requires the knowledge of double parton distribution functions (dPDFs). These quantities represent also a novel tool for the study of the three-dimensional nucleon structure, complementary to the possibilities offered by electromagnetic probes. In this paper we analyze dPDFs using Poincare covariant predictions obtained by using a Light-Front constituent quark model proposed in a recent paper, and QCD evolution. We study to what extent factorized expressions for dPDFs, which neglect, at least in part, two-parton correlations, can be used. We show that they fail in reproducing the calculated dPDFs, in particular in the valence region. Actually measurable processes at existing facilities occur at low longitudinal momenta of the interacting partons; to have contact with these processes we have analyzed correlations between pairs of partons of different kind, finding that, in some cases, they are strongly suppressed at low longitudinal momenta, while for other distributions they can be sizeable. For example, the effect of gluon-gluon correlations can be as large as 20 %. We have shown that these behaviors can be understood in terms of a delicate interference of non-perturbative correlations, generated by the dynamics of the model, and perturbative ones, generated by the model independent evolution procedure. Our analysis shows that at LHC kinematics two-parton correlations can be relevant in DPS, and therefore we address the possibility to study them experimentally.
Address [Rinaldi, Matteo; Scopetta, Sergio] Univ Perugia, Dipartimento Fis & Geol, I-06123 Perugia, Italy, Email: matteo.rinaldi@pg.infn.it;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000386670400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 2847
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Author Courtoy, A.; Noguera, S.; Scopetta, S.
Title Double parton distributions in the pion in the Nambu-Jona-Lasinio model Type Journal Article
Year 2019 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 12 Issue 12 Pages 045 - 26pp
Keywords (down) Deep Inelastic Scattering (Phenomenology); Phenomenological Models
Abstract Two-parton correlations in the pion, a non perturbative information encoded in double parton distribution functions, are investigated in the Nambu-Jona-Lasinio model. It is found that double parton distribution functions expose novel dynamical information on the structure of the pion, not accessible through one-body parton distributions, as it happens in several estimates for the proton target and in a previous evaluation for the pion, in a light-cone framework. Expressions and predictions are given for double parton distributions corresponding to leading-twist Dirac operators in the quark vertices, and to different regularization methods for the Nambu-Jona-Lasinio model. These results are particularly relevant in view of forthcoming lattice data.
Address [Courtoy, Aurore] Univ Nacl Autonoma Mexico, Inst Fis, Apartado Postal 20-364, Mexico City 01000, DF, Mexico, Email: aurore.courtoy@fisica.unam.mx;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:000521231400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4343
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Author Perez Adan, D.; Bahl, H.; Grohsjean, A.; Martin Lozano, V.; Schwanenberger, C.; Weiglein, G.
Title A new LHC search for dark matter produced via heavy Higgs bosons using simplified models Type Journal Article
Year 2023 Publication Journal of High Energy Physics Abbreviated Journal J. High Energy Phys.
Volume 08 Issue 8 Pages 151 - 27pp
Keywords (down) Dark Matter at Colliders; Specific BSM Phenomenology
Abstract Searches for dark matter produced via scalar resonances in final states consisting of Standard Model (SM) particles and missing transverse momentum are of high relevance at the LHC. Motivated by dark-matter portal models, most existing searches are optimized for unbalanced decay topologies for which the missing momentum recoils against the visible SM particles. In this work, we show that existing searches are also sensitive to a wider class of models, which we characterize by a recently presented simplified model framework. We point out that searches for models with a balanced decay topology can be further improved with more dedicated analysis strategies. For this study, we investigate the feasibility of a new search for bottom-quark associated neutral Higgs production with a b (b) over barZ + p(T)(miss) final state and perform a detailed collider analysis. Our projected results in the different simplified model topologies investigated here can be easily reinterpreted in a wide range of models of physics beyond the SM, which we explicitly demonstrate for the example of the Two-Higgs-Doublet model with an additional pseudoscalar Higgs boson.
Address [Adan, Danyer Perez; Schwanenberger, Christian; Weiglein, Georg] Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany, Email: danyer.perez.adan@desy.de;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1029-8479 ISBN Medium
Area Expedition Conference
Notes WOS:001073505200003 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5702
Permanent link to this record