The neutron electric dipole form factor in the perturbative chiral quark model

The current status of electric dipole moments of diamagnetic atoms which involves the synergy between atomic experiments and three different theoretical areas -particle, nuclear and atomic is reviewed. Various models of particle physics that predict CP violation, which is necessary for the existence of such electric dipole moments, are presented. These include the standard model of particle physics and various extensions of it. Effective hadron level combined charge conjugation (C) and parity (P) symmetry violating interactions are derived taking into consideration different ways in which a nucleon interacts with other nucleons as well as with electrons. Nuclear structure calculations of the CP-odd nuclear Schiff moment are discussed using the shell model and other theoretical approaches. Results of the calculations of atomic electric dipole moments due to the interaction of the nuclear Schiff moment with the electrons and the P and time-reversal (T) symmetry violating tensor-pseudotensor electron-nucleus are elucidated using different relativistic many-body theories. The principles of the measurement of the electric dipole moments of diamagnetic atoms are outlined. Upper limits for the nuclear Schiff moment and tensor-pseudotensor coupling constant are obtained combining the results of atomic experiments and relativistic many-body theories. The coefficients for the different sources of CP violation have been estimated at the elementary particle level for all the diamagnetic atoms of current experimental interest and their implications for physics beyond the standard model is discussed. Possible improvements of the current results of the measurements as well as quantum chromodynamics, nuclear and atomic calculations are suggested. .+y Nuclear tests of fundamental interactions and symmetries -31.15.ve Electron correlation calculations for atoms and ions: ground state PACS Higgs doublet modelsThe Higgs boson was recently discovered [4,5], but the detailed Higgs potential is still unknown. There are currently many well-motivated extensions of the Higgs sector BSM. The most well-known one is the two-Higgs doublet model (2HDM), and extensive studies have been performed [79,80,81,82,83,84,85,86,87,88,89,90,91,92,93,94,95,96,97].As the Higgs boson has a small coupling with light fermions, the one-loop level fermion EDM and the CP-odd four-fermion interactions are suppressed in 2HDM [98,99]. The leading contribution to the elementary level CP violation contributing to the EDM is the two-loop level Barr-Zee type diagram [79] [ Fig. 4 (b)], enhanced by the large Yukawa coupling of the top quark of the inner loop. The Barr-Zee type diagram contribution to the EDM of SM fermion can be written as [79]

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“…The NSM contribution was estimated in Ref. [268] as dXe ∼ 10 −36 e cm, (272) dHg ∼ 10 −35 e cm, (273) dRa ∼ 10 −32 e cm.…”

Section: Implication For Particle Physicsmentioning

confidence: 99%

Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation

et al. 2017

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“…[12]. We use the form factors of [13] to convert this into quark EDM bounds: d n ∼ 1.77d d − 0.48d u . The result (2.1) gives |α γ | 6 × 10 −8 GeV −2 .…”

Section: The 1-loop Contribution Of O W To the Neutron Edmmentioning

confidence: 99%

Searches forCP-violating dimension-6 electroweak gauge boson operators

Gripaios¹,

Sutherland²

2014

Phys. Rev. D

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We reconsider the prospects for observing a dimension-6, CP -violating operator involving W + W − Z at the LHC. Firstly, we correct a number of earlier calculations of the loop contribution to the the neutron electric dipole moment of a companion operator, involving W + W − γ, showing that measurements imply a very strong bound on the companion operator. Secondly, we quantify the link between the two operators, showing that strongly-coupled new physics could only be observable in proposed searches if it appeared at a scale below ∼ 170 GeV. This is most unlikely, given the null results of other searches at the LHC and elsewhere.arXiv:1309.7822v2 [hep-ph]

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“…For instance, in the constituent quark model ρ d n = 4 3 = −4ρ u n and ρ s n = 0 [1], whereas in the parton quark model ρ u n = −0.508, ρ d n = 0.746, and ρ s n = −0.226 [5]. From the various models proposed in the literature [1,5,41], we may conclude that…”

Section: Neutron Edmmentioning

confidence: 94%

Fermion EDMs with minimal flavor violation

Lee

et al. 2014

J. High Energ. Phys.

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Abstract:We study the electric dipole moments (EDMs) of fermions in the standard model supplemented with right-handed neutrinos and its extension including the neutrino seesaw mechanism under the framework of minimal flavor violation (MFV). In the quark sector, we find that the current experimental bound on the neutron EDM does not yield a significant restriction on the scale of MFV. In addition, we consider how MFV may affect the contribution of the strong theta-term to the neutron EDM. For the leptons, the existing EDM data also do not lead to strict limits if neutrinos are Dirac particles. On the other hand, if neutrinos are Majorana in nature, we find that the constraints become substantially stronger. Moreover, the results of the latest search for the electron EDM by the ACME Collaboration are sensitive to the MFV scale of order a few hundred GeV or higher. We also look at constraints from CP -violating electron-nucleon interactions that have been probed in atomic and molecular EDM searches.

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The neutron electric dipole form factor in the perturbative chiral quark model

Cited by 30 publications

References 73 publications

Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation

Probing exotic phenomena at the interface of nuclear and particle physics with the electric dipole moments of diamagnetic atoms: A unique window to hadronic and semi-leptonic CP violation

Searches forCP-violating dimension-6 electroweak gauge boson operators

Fermion EDMs with minimal flavor violation

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