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Related papers: CP asymmetries in neutralino production

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We discuss the observability of CP-violating asymmetries in the process e+ e- -> X_1^0 X_2^0 -> X_1^0 X_1^0 l+ l-, with l = e,mu. We consider two examples of supersymmetric scenarios: (i) with decays X_2^0 -> l_R l -> X_1^0 l+ l-; (ii) with…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. A. Aguilar-Saavedra

Neutralinos $\tilde{\chi}^0$ in supersymmetric theories, the spin--1/2 Majorana--type superpartners of the U(1) and SU(2) neutral electroweak gauge bosons and SU(2) neutral Higgs bosons, are expected to be among light supersymmetric…

High Energy Physics - Phenomenology · Physics 2009-01-07 S. Y. Choi , B. C. Chung , J. Kalinowski , Y. G. Kim , K. Rolbiecki

We study the CP-violating terms of the spin-spin correlations in chargino production e+e- -> chi^+/-_1 chi^-/+_2, and their subsequent two-body decays into sneutrinos plus leptons. We propose novel CP-sensitive observables with the help of…

High Energy Physics - Phenomenology · Physics 2008-11-26 A. Bartl , K. Hohenwarter-Sodek , T. Kernreiter , O. Kittel , M. Terwort

Selectron decays constitute a source of 100% polarised neutralinos, whose helicity is fixed by the charge and "chirality" of the decaying selectron. In SUSY scenarios where the second neutralino X_2^0 has three-body decays, the cascade…

High Energy Physics - Phenomenology · Physics 2009-11-10 J. A. Aguilar-Saavedra

We study the production of the lightest neutralinos in the radiative process $e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma$ in low energy supersymmetric models for the International Linear Collider energies. This includes the minimal…

High Energy Physics - Phenomenology · Physics 2008-11-26 Rahul Basu , P. N. Pandita , Chandradew Sharma

We study the distribution of lepton pairs from the second lightest neutralino decay \tchi^0_2\to\tchi^0_1 l^+l^-. This decay mode is important to measure the mass difference between \tchi^0_2 and the lightest neutralino \tchi^0_1, which…

High Energy Physics - Phenomenology · Physics 2008-11-26 Mihoko M. Nojiri , Youichi Yamada

In the CP-invariant supersymmetric theories, the steep S-wave (slow P-wave) rise of the cross section for any non-diagonal neutralino pair production in $e^+ e^-$ annihilation, $e^+e^- \to \tilde{\chi}^0_i \tilde{\chi}^0_j$ ($i \neq j$),…

High Energy Physics - Phenomenology · Physics 2009-11-10 S. Y. Choi

We study the production of the lightest neutralinos in the radiative process $e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma$ in low energy supersymmetric models for the International Linear Collider energies with longitudinally polarized…

High Energy Physics - Phenomenology · Physics 2015-06-03 P. N. Pandita , Chandradew Sharma

Approximately 438 pb-1 of e+e- data from the OPAL detector, taken with the LEP collider running at centre-of-mass energies of 192-209 Gev, are analyzed to search for evidence of chargino pair production, e+e- -> tilde chi^+_1 tilde chi^-_1,…

High Energy Physics - Experiment · Physics 2008-11-26 The OPAL collaboration , G. Abbiendi

In the Minimal Supersymmetric Standard Model with conserved R-parity, the decays of the next-to-lightest neutralino into the lightest neutralino and two leptons are always involved in each supersymmetric particle decay chain. In this thesis…

High Energy Physics - Phenomenology · Physics 2016-09-08 Qingjun Xu

In the CP-violating Minimal Supersymmetric Standard Model, we study the pair production of neutralinos at center-of-mass energies around the heavy neutral Higgs boson resonances. For longitudinally polarized muon beams, we analyze CP…

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

A search for the electroweak production of supersymmetric particles in proton-proton collisions at a center-of-mass energy of 13 TeV is presented in final states with a $\tau$ lepton pair. Both hadronic and leptonic decay modes are…

High Energy Physics - Experiment · Physics 2018-12-03 CMS Collaboration

Charginos $\tilde{\chi}^\pm$ and neutralinos $\tilde{\chi}^0$ in supersymmetric theories can be produced copiously at $e^+e^-$ colliders and their properties can be measured with high accuracy. Consecutively to the chargino system, in which…

High Energy Physics - Phenomenology · Physics 2011-09-13 S. Y. Choi , J. Kalinowski , G. Moortgat-Pick , P. M. Zerwas

$CP$ violating phenomena predicted by the minimal supersymmetric standard model are discussed in a case where the $CP$ violating phases in SUSY sector are not suppressed. The electric dipole moments of the neutron and the electron are…

High Energy Physics - Phenomenology · Physics 2015-06-25 Yoshiki Kizukuri , Noriyuki Oshimo

A search for the electroweak production of charginos, neutralinos and sleptons decaying into final states involving two or three electrons or muons is presented. The analysis is based on 36.1 fb$^{-1}$ of $\sqrt{s}=13$ TeV proton-proton…

High Energy Physics - Experiment · Physics 2019-01-11 ATLAS Collaboration

Supersymmetric extensions of the Standard Model provide new sources of CP violation. Here the CP properties of neutralinos are described and possible experimental signatures of CP--violation in the neutralino production processes at e+e-…

High Energy Physics - Phenomenology · Physics 2009-12-15 J. Kalinowski

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

We study radiative neutralino production e^+e^- \to \tilde\chi^0_1 \tilde\chi^0_1\gamma at the linear collider with longitudinally polarised beams. We consider the Standard Model background from radiative neutrino production e^+e^- \to \nu…

High Energy Physics - Phenomenology · Physics 2008-11-26 Herbi K. Dreiner , Olaf Kittel , Ulrich Langenfeld

Results are presented from a search for the electroweak production of supersymmetric particles in pp collisions in final states with two tau leptons. The data sample corresponds to an integrated luminosity between 18.1 inverse femtobarns…

High Energy Physics - Experiment · Physics 2017-04-11 CMS Collaboration

Recent studies about CP violation in the Minimal Supersymmetric Standard Model (MSSM) with complex parameters are reviewed. In order to unambiguously identify the CP-violating phenomena it is necessary to study CP-odd or T-odd observables.…

High Energy Physics - Phenomenology · Physics 2009-02-16 S. Hesselbach