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Related papers: ATLAS Violating CP Effectively

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We study the pair-production of charginos in the CP-violating Minimal Supersymmetric Standard Model at center-of-mass energies around the heavy neutral Higgs boson resonances. If these resonances are nearly degenerate, as it can happen in…

High Energy Physics - Phenomenology · Physics 2009-01-06 Olaf Kittel , Federico von der Pahlen

New sources of charge-parity (CP) violation beyond those described in the Standard Model (SM) are required to explain the observed matter--antimatter asymmetry of the Universe. The Standard Model Effective Field Theory (SMEFT) provides a…

High Energy Physics - Phenomenology · Physics 2026-04-27 Avalon Roberts , Patrick Dougan , Alexander Oh , Savanna Shaw

We study the prospect of determining the CP violating phase in $\tau$-lepton Yukawa coupling at the Large Hadron Collider (LHC). While the current run is already exploring the production of a pair of the third generation $\tau$ leptons from…

High Energy Physics - Phenomenology · Physics 2019-08-15 Akanksha Bhardwaj , Partha Konar , Pankaj Sharma , Abhaya Kumar Swain

A review of recent multiboson and vector boson scattering (VBS) measurements from the ATLAS and CMS Collaborations at the LHC is presented. Results are reported from precision diboson cross-section measurements, novel CP-sensitive and…

High Energy Physics - Experiment · Physics 2026-04-17 Santiago Folgueras

We study CP violation in the lepton sector of the supersymmetric extension of the Standard Model with three generations of massive singlet neutrinos with Yukawa couplings $Y_\nu$ to lepton doublets, in a minimal seesaw model for light…

High Energy Physics - Phenomenology · Physics 2008-11-26 John Ellis , Junji Hisano , Smaragda Lola , Martti Raidal

This letter presents evidence for the associated production of a W boson and a top quark using 2.05 fb^-1 of pp collision data at sqrt(s) = 7 TeV accumulated with the ATLAS detector at the LHC. The analysis is based on the selection of the…

High Energy Physics - Experiment · Physics 2015-03-20 ATLAS Collaboration

The violation of CP symmetry is one of Sakharov's conditions for the matter-antimatter asymmetry of the Universe. Currently known sources of CP violation in the quark and neutrino sectors are insufficient to account for this. Is CP also…

CP-violation (CPV) is a rare phenomenon in the Standard Model whilst there is compelling indirect evidence for additional CPV sources in the Universe. The search for CPV effects at the LHC is thus one of the best-motivated precision tests…

High Energy Physics - Phenomenology · Physics 2024-09-04 Alejo N. Rossia , Eleni Vryonidou

We investigate possible CP violating effects in $e^+e^-$ annihilation into top quark pairs. One of the interesting observable effects is the difference in production rates between the two CP conjugate polarized states $t_L\bar t_L$ and…

High Energy Physics - Phenomenology · Physics 2009-09-01 Darwin Chang , Wai-Yee Keung , Ivan Phillips

Simply based on CP arguments, we argue against a Standard Model explanation of the baryon asymmetry of the universe in the presence of a first order phase transition. A CP-asymmetry is found in the reflection coefficients of quarks hitting…

High Energy Physics - Phenomenology · Physics 2008-11-26 M. B. Gavela , P. Hernández , J. Orloff , O. Pène

We consider the impact of CP-violating Higgs and top interactions on diboson production from gluon fusion within the Standard Model Effective Field Theory framework. We systematically study differential distributions for double Higgs,…

High Energy Physics - Phenomenology · Physics 2024-11-05 Marion O. A. Thomas , Eleni Vryonidou

Assuming CP violation arises solely through the Higgs potential, we develop the most general two-Higgs doublet model. There is no discrete symmetry that distinguishes the two Higgs bosons. It is assumed that an approximate global family…

High Energy Physics - Phenomenology · Physics 2010-11-01 Yue-Liang Wu , Lincoln Wolfenstein

Searches for physics beyond the standard model are considered one of the corner stones of the physics program at the two multipurpose experiments, ATLAS and CMS, at the LHC. Both experiments have conducted numerous searches for new…

High Energy Physics - Experiment · Physics 2019-08-14 Claudia Seitz

The study of $CP$ violation in hyperon transitions has a long history. In the early 2000s the HyperCP experiment made a major effort to seek $CP$-odd signals in the decay sequence $\Xi^-\to\Lambda \pi^-$ and $\Lambda\to p\pi^-$, which…

High Energy Physics - Phenomenology · Physics 2026-01-07 Xiao-Gang He , Xiao-Dong Ma , Jusak Tandean , German Valencia

In this paper, we put constraints on anomalous $\mathcal{CP}$-violating top-Higgs couplings using the currently available Higgs data and explore the prospect of measuring these couplings at 240 GeV TLEP. We find that the…

High Energy Physics - Phenomenology · Physics 2015-06-19 Archil Kobakhidze , Lei Wu , Jason Yue

We explore charged-Higgs CP-violating effects in an intriguing two-Higgs doublet model which accords special status to the top quark. In this model the heaviness of the top quark originates naturally from the much larger VEV of the second…

High Energy Physics - Phenomenology · Physics 2009-10-31 Ken Kiers , Amarjit Soni , Guo-Hong Wu

The LHC is the new b-hadron factory and will be dominating flavour physics until the start of Belle II, and beyond in many decay modes. While the $B$ factories and Tevatron experiments are still analysing their data, ATLAS, CMS and LHCb are…

High Energy Physics - Experiment · Physics 2015-10-13 Patrick Koppenburg

Results are presented from a search for CP violation in top quark pair production, using proton-proton collisions at a center-of-mass energy of 13 TeV. The data used for this analysis consist of final states with two charged leptons…

High Energy Physics - Experiment · Physics 2023-07-21 CMS Collaboration

We show that models in which the strong $CP$ problem is solved by introducing an axion field with a mass enhanced by non-QCD UV dynamics at a scale $\Lambda_{\rm SI}$ exhibit enhanced sensitivity to external sources of $CP$ violation. In…

High Energy Physics - Phenomenology · Physics 2022-08-05 Ravneet S. Bedi , Tony Gherghetta , Maxim Pospelov

We study CP violation in a multi-Higgs doublet model based on a $S_3 \times Z_3$ horizontal symmetry. We consider two mechanisms for CP violation in this model: a) CP violation due to complex Yukawa couplings; and b) CP violation due to…

High Energy Physics - Phenomenology · Physics 2010-11-01 N. G. Deshpande , Xiao-Gang He