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Related papers: Strong CP problem, Neutron EDM and Thermal QCD sum…

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Lattice QCD is rapidly progressing toward being able to reliably compute the electric dipole moment of the neutron as a function of the strong CP-violating parameter theta. Present day calculations are performed at unphysical values of the…

High Energy Physics - Lattice · Physics 2014-11-17 Donal O'Connell , Martin J. Savage

The pion nucleon vertex function at finite temperature is studied in the framework of: (a) the thermal (linear) sigma model to leading (one-loop) order, and (b) a thermal QCD-Finite Energy Sum Rule. Results from both methods indicate that…

High Energy Physics - Phenomenology · Physics 2009-10-31 C. A. Dominguez , C. van Gend , M. Loewe

The catalysis of chiral symmetry breaking by a magnetic field in the massless weak-coupling phase of QED is studied. The dynamical mass of a fermion (energy gap in the fermion spectrum) is shown to depend essentially nonanalytically on the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Valery P. Gusynin

We present a comprehensive study of the finite temperature CP-asymmetry factor needed in the semi-classical treatment of leptogenesis originating from Majorana fermion decays into a lepton and a scalar particle. The imaginary part of the…

High Energy Physics - Phenomenology · Physics 2025-06-13 Károly Seller , Zsolt Szép , Zoltán Trócsányi

We investigate the effects of the spontaneous CP violation at finite temperature in the Minimal Supersymmetric Standard Model on the baryogenesis at the weak scale. After a brief discussion of the case in which the electroweak phase…

High Energy Physics - Phenomenology · Physics 2010-03-17 D. Comelli , M. Pietroni , A. Riotto

By studying the effective potential of the MSSM at finite temperature, we find that CP can be spontaneously broken in the intermediate region between the symmetric and broken phases separated by the bubble wall created at the phase…

High Energy Physics - Phenomenology · Physics 2009-10-31 K. Funakubo , A. Kakuto , S. Otsuki , F. Toyoda

Cold electroweak baryogenesis was proposed as a scenario to bypass generic problems of electroweak baryogenesis within the Standard Model. In this scenario, baryogenesis takes place during an electroweak symmetry breaking transition, which…

High Energy Physics - Phenomenology · Physics 2009-11-11 Anders Tranberg , Jan Smit

Using an effective theory approach, we calculate the neutron electric dipole moment (nEDM) in the minimal left-right symmetric model with both explicit and spontaneous CP violations. We integrate out heavy particles to obtain flavor-neutral…

High Energy Physics - Phenomenology · Physics 2015-05-14 Fanrong Xu , Haipeng An , Xiangdong Ji

It is argued that QCD might solve the strong CP problem on its own. To test this idea, a lattice simulation suggests itself. In view of the difficulty of such a calculation we have, as a first step, investigated the problem in the $CP^3$…

High Energy Physics - Lattice · Physics 2015-06-25 G. Schierholz

The recent lattice QCD calculations of the neutron and proton electric dipole moments (EDMs) and the CP-violating $\pi {\rm NN}$ coupling constant due to the $\theta$ term are reviewed. Progress towards nucleon EDM calculations, including…

High Energy Physics - Lattice · Physics 2024-11-26 Keh-Fei Liu

The effects of the CP violating $\theta$ term in the QCD Lagrangian upon low energy hadronic phenomenology are reconsidered. Strong CP violating interactions among Goldstone bosons and octet baryons are incorporated into an effective chiral…

High Energy Physics - Phenomenology · Physics 2010-11-01 Peter Cho

A permanent electric dipole moment (EDM) of a particle or system is a separation of charge along its angular-momentum axis and is a direct signal of T-violation and, assuming CPT symmetry, CP violation. For over sixty years EDMs have been…

Atomic Physics · Physics 2019-02-08 Timothy Chupp , Peter Fierlinger , Michael Ramsey-Musolf , Jaideep Singh

CP-nonconserving effects in the reaction p p-bar -> t b-bar +X -> W^+ b b-bar +X, driven by the supersymmetric CP-odd phase of the stop trilinear soft breaking term, \arg(A_t), are studied. We discuss the CP-nonconserving effects in both…

High Energy Physics - Phenomenology · Physics 2009-10-30 S. Bar-Shalom , D. Atwood , A. Soni

The spontaneous breaking of CP symmetry in 4D SU($N$) pure Yang-Mills theory at $\theta=\pi$ has recently attracted much attention in the context of the higher-form symmetry and the 't Hooft anomaly matching condition. Here we use Monte…

High Energy Physics - Theory · Physics 2025-05-09 Mitsuaki Hirasawa , Masazumi Honda , Akira Matsumoto , Jun Nishimura , Atis Yosprakob

We study the implications of a light stop for the spontaneous CP breaking at finite temperature in the Higgs sector of the Minimal Supersymmetric Standard Model with a gauge singlet. Assuming CP conservation at zero temperature, we show…

High Energy Physics - Phenomenology · Physics 2010-11-01 D. Comelli , M. Pietroni , A. Riotto

We perform the first investigation of cold electroweak baryogenesis in the two Higgs-doublet model (2HDM). The electroweak symmetry breaking transition is assumed to occur through a spinodal instability from a super-cooled initial state. We…

High Energy Physics - Phenomenology · Physics 2015-06-04 Anders Tranberg , Bin Wu

The strong CP-violating parameter is small today as indicated by constraints on the neutron electric dipole moment. In the early universe, the QCD axion has not yet relaxed to its QCD-cancelling minimum and it is natural to wonder whether…

High Energy Physics - Phenomenology · Physics 2014-10-29 Geraldine Servant

Nucleon electric dipole moments originating from strong CP-violation are being calculated by several groups using lattice QCD. We revisit the finite volume corrections to the CP-odd nucleon matrix elements of the electromagnetic current,…

High Energy Physics - Phenomenology · Physics 2014-07-25 Tarik Akan , Feng-Kun Guo , Ulf-G. Meißner

We review the present status of CP violating problem in supersymmetric extensions of the standard model. We analyze the constraints imposed by the experimental limits of the electron, neutron, and mercury electric dipole moments on the…

High Energy Physics - Phenomenology · Physics 2014-11-17 Shaaban Khalil

We consider hadronic CP violation induced by chromoelectric dipolemoments (CEDMs) of light quarks and the QCD theta parameter ($?overline{?theta}$). We concentrate on the strange quark CEDM especially in this paper. Using effective CP…

High Energy Physics - Phenomenology · Physics 2011-07-19 Junji Hisano , Yasuhiro Shimizu