Little Higgs theories often rely on an internal parity ("T-parity'') to suppress non-standard electroweak effects or to provide a dark matter candidate. We show that such a symmetry is generally broken by anomalies, as described by the Wess-Zumino-Witten term. We study a simple SU(3) x SU(3)/SU(3) Little Higgs scheme where we obtain a minimal form for the topological interactions of a single Higgs field. The results apply to more general models, including [SU(3) x SU(3)/SU(3)]^4, SU(5)/SO(5), and SU(6)/Sp(6).
The solar and atmospheric neutrino anomalies constitute the only solid and most remarkable evidence for physics beyond the Standard Model, indicating that the lepton mixing matrix is fundamentally distinct from that describing the quarks. Here I will report on how supersymmetry with spontaneously or bilinearly broken R Parity provides a predictive theory for neutrino mass and mixing which leads to a solution of neutrino anomalies which can be clearly tested at high energy accelerators.
Neutrino mass spectrum is reanalyzed in supersymmetric models with explicit trilinear $R$ violation. Models in this category are argued to provide simultaneous solution to the solar and atmospheric neutrino anomalies. It is shown specifically that large mixing and hierarchical masses needed for the vacuum solution of neutrino anomalies arise naturally in these models without requiring any additional symmetries or hierarchies among the trilinear couplings.
In a class of supersymmetric left-right models (SUSYLR) of weak interactions where R-parity is automatically conserved, we show that spontaneous breakdown of parity CANNOT occur without spontaneous breakdown of R-parity. This intriguing result connects two physically different scales in supersymmetric models.
A long-lived decaying dark matter as a resolution to Fermi, PAMELA and ATIC anomalies is investigated in the framework of split supersymmetry (SUSY) without R-parity, where the neutralino is regarded as the dark matter and the extreme fine-tuned couplings for the long-lived neutralino are naturally evaded in the usual approach.
We suggest simple models of spontaneous parity violation in supersymmetric strong gauge theory. We focus on left-right symmetric model and investigate vacuum with spontaneous parity violation. Non-perturbative effects are calculable in supersymmetric gauge theory, and we suggest two new models. The first model shows confinement, and the second model has a dual description of the theory. The left-right symmetry breaking and electroweak symmetry breaking are simultaneously occurred with the suitable energy scale hierarchy. The second model also induces spontaneous supersymmetry breaking.
The effective super-renormalizable 3-dimensional Lagrangian, describing the high temperature limit of chiral gauge theories, has more symmetry than the original 4d Lagrangian: parity violation is absent. Parity violation appears in the 3d theory only through higher-dimensional operators. We compute the coefficients of dominant P-odd operators in the Standard Electroweak theory and discuss their implications. We also clarify the parametric accuracy obtained with dimensional reduction.
We discuss an optimal $R$-parity breaking SUSY solution to the $R_b$ excess as well as the ALEPH 4-jet anomaly. The latter arises from the pair production of stop via chargino decay at LEP1.5, followed by its $R$--violating decay into a light quark pair. The model satisfies top quark and $Z$--boson decay constraints along with gaugino mass unification.
In this paper, we consider a solution to explain the three discrepancies with the standard model (SM) predictions in flavor observables, i.e. anomalies in $B\rightarrow K^\astμ^+μ^-$ and $R_K=\mathcal{B}(B\rightarrow Kμ^+μ^-)/\mathcal{B}(B\rightarrow K e^+e^-)$ at the LHCb and an excess in $h\rightarrow μτ$ at the CMS in the context of R-parity violating (RPV) supersymmetry. We demonstrate that these anomalies can be explained within a unified framework: the minimal supersymmetry model (MSSM) extended with $5+\overline{5}$ vectorlike (VL) particles. The new trilinear RPV couplings involving VL…
The possibility of parity violation through spacetime torsion has been explored in a scenario containing fields with different spins. Taking the Kalb-Ramond field as the source of torsion, an explicitly parity violating $U(1)_{EM}$ gauge invariant theory has been constructed by extending the KR field with a Chern-Simons term.
Core collapse supernovae are dominated by weakly interacting neutrinos. This provides a unique opportunity for macroscopic parity violation. We speculate that parity violation in a strong magnetic field can lead to an asymmetry in the explosion and a recoil of the newly formed neutron star. We estimate the asymmetry from neutrino-polarized-neutron elastic scattering, polarized electron capture and neutrino-nucleus elastic scattering in a (partially) polarized electron gas.
The generalization of the Vafa-Witten theorem ruling out parity violation to QCD at finite temperature is considered. It is shown that this generalization of the theorem rules out Lorentz-invariant parity violating operators from spontaneously acquiring vacuum expectation values. However, it does not rule out Lorentz-noninvariant parity-violating operators from acquiring expectation values. Other situations where the theorem is inapplicable are also discussed.
We examine the parameter space of supersymmetric models with $R$-parity violating interactions of the form $λ' L Q D^c$ to explain the various anomalies observed in $b \rightarrow s \ell \ell$ transitions. To generate the appropriate operator in the low energy theory, we are led to a region of parameter space where loop contributions dominate. In particular, we concentrate on parameters for which diagrams involving winos, which have not been previously considered, give large contributions. Many different potentially constraining processes are analyzed, including $τ\rightarrow μμμ$, $B_s-\bar{B…
The fate of R-parity in supersymmetric theories is discussed in detail. We make a strong case for R-parity violation showing that the simplest theories based on the local B-L symmetry predict the spontaneous breaking of R-parity at the SUSY scale. The possible implications for the searches at the Large Hadron Collider are discussed.
Core collapse supernovae are gigantic explosions of massive stars that radiate 99% of their energy in neutrinos. This provides a unique opportunity for large scale parity or charge conjugation violation. Parity violation in a strong magnetic field could lead to an asymmetry in the neutrino radiation and recoil of the newly formed neutron star. Charge conjugation violation in the neutrino-nucleon interaction reduces the ratio of neutrons to protons in the neutrino driven wind above the neutron star. This is a problem for r-process nucleosynthesis in this wind. On earth, parity violation is an e…
I discuss the theoretical motivations for R-parity violation, review the experimental bounds and outline the main changes in collider phenomenology compared to conserved R-parity. I briefly comment on the effects of R-parity violation on cosmology.
We overview the dark parity violation, which means the parity violation induced by a dark gauge boson of very small mass and coupling. When a dark gauge boson has an axial coupling, as in dark Z model, it can change the effective Weinberg angle in the low-energy experiments such as the atomic parity violation and the low-Q^2 polarized electron scatterings. Such low-energy parity tests are an excellent probe of the dark force.
B-decays mediated by both charged currents and neutral currents have provided hints of violation of lepton flavour universality. By assuming an explanation of these anomalies in terms of new physics at the TeV scale affecting the third fermion generation, we review the relevant constraints. In particular we illustrate the effects of electroweak radiative corrections and their impact on a consistent interpretation of the data. The simplest scenario is ruled out and we briefly discuss the modifications required to simultaneously describe the whole set of anomalies.
Electromagnetic resonant cavities form the basis for a number modern tests of Lorentz invariance. The geometry of most of these experiments implies unsuppressed sensitivities to parity-even Lorentz violations only. Parity-odd violations typically enter through suppressed boost effects, causing a reduction in sensitivity by roughly four orders of magnitude. Here we discuss possible techniques for achieving unsuppressed sensitivities to parity-odd violations by using asymmetric resonators.
We investigate the effects of R-parity violation on the semileptonic decays of B-meson in the minimal supersymmetric standard model with explicit R-parity violation and discuss its physical implications. We find that the semileptonic decays of B-meson can be largely affected by the R-parity violation.
We derive effective actions for parity-violating fluids in both $(3+1)$ and $(2+1)$ dimensions, including those with anomalies. As a corollary we confirm the most general constitutive relations for such systems derived previously using other methods. We discuss in detail connections between parity-odd transport and underlying discrete symmetries. In (3+1) dimensions we elucidate connections between anomalous transport coefficients and global anomalies, and clarify a previous puzzle concerning transports and local gravitational anomalies.
In a space-time with torsion, the action for the gravitational field can be extended with a parity-violating piece. We show how to obtain such a piece from geometry itself, by suitably modifying the affine connection so as to include a pseudo-tensorial part. A consistent method is thus suggested for incorporating parity-violation in the Lagrangians of all matter fields with spin in a space-time background with torsion.
In the last few years, the ratios $R_{D^{(*)}}$ and of $R_{K^{(*)}}$ have reportedly exhibited significant deviations from the relevant Standard Model predictions, hinting towards a possible violation of Lepton Flavor Universality and a window to New Physics. We investigate to what extent the inclusion of R-parity violating couplings in the Minimal Supersymemtric Standard Model can provide a better fit to the anomalies simultaneously. We perform this analysis employing an approximate, non-abelian $\mathcal{G}_f=U(2)_q \times U(2)_\ell$ flavour symmetry, which features a natural explanation of …
I discuss in qualitative terms the implications of the recent measurement by C. S. Wood et al. of the hyperfine dependence of atomic parity violation in 133Cs. The derived anapole moment constrains the strength of hadronic parity violation.
In this lectures, we give a review about the Minimal Supersymmetric Standard Model (MSSM) with $R$-Parity Violation because it provides an attractive way to generate neutrino masses, lepton mixing angles in acconcordance to present neutrino data.
The MSSM with $R$-Parity violation allows flavour changing neutral currents through two mechanisms, directly through one loop diagrams, and indirectly through the generation of flavour violation in the sparticle sector. We discuss the use of these mechanisms for constraining $R$-Parity violation, and show that the indirect mechanism parametrised in terms of the running of the soft masses from the unification or Planck scale typically dominates previously calculated effects. We discuss neutrino mass generation, $μ\to eγ$, $b\to sγ$, and $K^0-\bar K^0$ mixing as examples.
The study of parity-violation in semi-leptonic processes has yielded important insights into the structure of the Standard Model and the substructure of the nucleon. I discuss the future of semi-leptonic parity-violation and the role it might play in uncovering physics beyond the Standard Model.
Supernovae provide a unique opportunity for large scale parity violation because they are dominated by neutrinos. We calculate the parity violating asymmetry A of neutrino emission in a strong magnetic field. We assume the neutrinos elastically scatter many times from slightly polarized neutrons. Because of multple interactions, A grows with the optical thickness of the proto-neutron star and may be much larger than previous estimates. As a result, the neutron star could recoil at a significant velocity.
Besides the fact of parity violation in weak interactions, based on evidences from neutrino oscillation and tritium beta decay, a natural conjecture is that neutrinos may be spacelike particles with a tiny proper mass. A Dirac-type equation for spacelike neutrinos is further investigated and its solutions are discussed. This equation can be written in two spinor equations coupled together via nonzero proper mass while respecting maximum parity violation.
We investigate the implications of $R$-Parity violation (RPV) for quark flavour violation both by constraining the sneutrino masses to be positive and by studying the processes $b\to sγ$ and $K^0-\bar K^0$ mixing. In the latter there are two major contributions, one from ``direct'' one loop diagrams involving RPV couplings, and one from the ``indirect'' contributions generated by the renormalisation group. We compare the effects and discuss the implications of our results.
We study the minimal gauged U(1)_{B-L} supersymmetric model and show that it provides an attractive theory for spontaneous R-parity violation. Both U(1)_{B-L} and R-parity are broken by the vacuum expectation value of the right-handed sneutrino (proportional to the soft SUSY masses), thereby linking the B-L and soft SUSY scales. In this context we find a consistent mechanism for generating neutrino masses and a realistic mass spectrum, all without extending the Higgs sector of the minimal supersymmetry standard model. We discuss the most relevant collider signals and the connection between the…
We present a complete analysis of Lepton Flavor Universality (LFU) violations in leptonic $τ$ decays in motivated models addressing the $B$-physics anomalies, based on the $SU(4)\times SU(3)\times SU(2)\times U(1)$ gauge group. We show that the inclusion of vector-like fermions, required by $B$-physics data, leads to sizable modifications of the leading-log results derived within an Effective Field Theory approach. In the motivated parameter-space region relevant to the $B$-physics anomalies, the models predict a few per-mil decrease of the effective $W$-boson coupling to $τ$, within the reach…
We construct basis-independent expressions that measure the magnitude of $R$-parity breaking due to possible superpotential terms in the Minimal Supersymmetric extension of the Standard Model, in the absence of soft supersymmetry-breaking terms and spontaneous gauge symmetry breaking. We also discuss briefly their application to a consistent treatment of cosmological constraints on $R$-parity violation.
Is gravity parity violating? Given the recent observations of gravitational waves from coalescing compact binaries, we develop a strategy to find an answer with current and future detectors. We identify the key signatures of parity violation in gravitational waves: amplitude birefringence in their propagation and a modified chirping rate in their generation. We then determine the optimal binaries to test the existence of parity violation in gravity, and prioritize the research in modeling that will be required to carry out such tests before detectors reach their design sensitivity.
We examine some flavor changing processes such as rare leptonic decays of the long-lived neutral kaon, muon-electron conversion in nuclei and radiative muon decay which are induced by the combined effects of bilinear and trilinear R-parity violations. These processes are used to put strong constraints on certain products of the bilinear and trilinear couplings. We also discuss the constraints on R-parity violation from neutrino masses and compare them with the constraints from flavor changing decay processes. Large range of parameter space satisfying the constraints from neutrino masses can be…
We discuss possible constraints on R-parity violation from recently announced Belle/Babar results on the B\toτνbranching fraction, and the bounds on τ^-\to\ell^- K_S^0 (\ell=e or μ) from Babar.
In the framework of the supersymmetric theories with R-parity violation we consider the process $γγ\to ν_i \bar{ν_j}$ and its contribution into energy loss from the stars.Under some conditions the studied contribution exceeds the standard model contribution to the same process.
We propose a new method, using the Andreev reflection at superconductors, to measure parity violation induced by the standard electroweak theory, which in turn constrains the possible parity-violating effects of new physics. The weak neutral currents induce parity-violating, marginal effective operators, though quite tiny, in superconductors. We estimate their effects on superconducting gaps and propose a method to measure the parity-violation from the spin polarization effect, when electrons or holes get Andreev-reflected at the interface between normal metal and a superconductor. Such polari…
We compute the neutralino decay rate in the minimal supersymmetric standard model with the addition of explicit R-parity violation. We include the complete squark and slepton mixing matrices, previously neglected, and we improve and correct published formulas. These decays are relevant to accelerator and non-accelerator searches for R-parity violation, and are especially interesting in light of the reported high Q^2 anomaly at HERA.
We investigate bounds from tree-level and one-loop processes in generic supersymmetric models with spontaneous R-parity breaking in the superpotential. We analyse the bounds from a general point of view. The bounds are applicable both for all models with spontaneous R-parity violation and for explicit bilinear R-parity violation based on general lepton-chargino and neutrino-neutralino mixings. We find constraints from semileptonic B, D and K decays, leptonic decays of the mu and tau, electric dipole moments, as well as bounds for the anomalous magnetic moment of the muon.
We have studied new CP violating effects in $Λ_b \to p π$ decay mode, that can arise in Minimal Supersymmetric Standard Model with R-parity violation. We have estimated how much R-parity violation modifies the Standard Model predictions for CP asymmetries within the present bounds. We found that in the R-parity violating model, the rate asymmetry ($a_{cp}$) is suppressed (about 10 times) and the asymmetry parameter $A(α)$ is enhanced (approximately $10^2$ times) with respect to the SM predictions.
Supersymmetry without R-parity predicts tree level quark flavor violation. We present a potential signal of single bottom production at electron-positron colliders with energies in the range 6 to 20 GeV. Taking into account rare decay limits it should be detectable with the current BaBar and Belle data samples.
We study CP violating B decays in the minimal supersymmetric standard model with R-parity violation. We estimate how much R-parity violation modifies the SM predictions for CP asymmetries in B decays within the present bounds. The effects of R-parity- and lepton-number-violating couplings on the ratio of the decay amplitude due to R-parity violation to that of the SM can differ by one or two orders of magnitudes depending on the models of the left-handed quark mixing. It is possible to disentangle the R-parity violating effects from those of the SM and R-parity- conserving supersymmetric model…
I consider parity violation of the chiral symmetry broken vacuum. It is shown that the parity of the true vacuum in the chiral symmetry breaking model is violated. I propose new mechanism of massive neutrino, which the neutrinos have mass in terms of the chiral symmetry breaking. In this mechanism, it may give us new understanding why almost neutrinos have left chirality. Further, NJL model is proposed as alternative phenomenological model of neutrinos.
A comparison of spectra obtained using the 1-loop MSSM and 2-loop R-parity violating MSSM renormalization group equations is presented. Influence of higher loop corrections and R-parity violating terms is discussed. Some numerical constraints on the R-parity violating parameters are also given.
We investigate possibilities for dynamical P-parity violation in dense baryon matter in the framework of effective quark models. Dynamical P-parity violation can appear in models with at least two scalar and two pseudoscalar fields, where both scalar fields are condensed at normal conditions. At special configurations of coupling constants, one of pseudoscalar fields can then also condense at some value of baryon density, the phenomenon results in mixing of the scalar and pseudoscalar physical degrees of freedom, hence, giving rise to P-parity violation. We discuss the implications and possibl…
In these Lectures we review the Minimal Supersymmetric Standard Model as well as some of its extensions that include R-Parity violation. The cases of spontaneous breaking of R-Parity as well as that of explicit violation through bilinear terms in the superpotential are studied in detail. The signals at LEP and the prospects for LHC are discussed.
Supersymmetric scenarios with R-parity conservation are becoming very constrained due to the lack of missing energy signals, thus motivating those scenarios with R-parity violation. In view of this, we consider a supersymmetric model with R-parity violation and extended by an anomalous horizontal $U(1)_H$ symmetry, where a self-consistent framework with baryon-number violation is achieved along with a proper supression for lepton number violating dimension-5 operators in order to keep a proton decay safe. With the introduction of right-handed neutrinos both Dirac and Majorana masses can be acc…
We consider a class of supersymmetric SU(3)\times SU(2)\times U(1) multihiggs models in which R-parity is violated through bilinear Higgs-lepton interactions. The required, due to R-parity violation, higgs-lepton rotations introduce an alternative way to generate the phenomenologically desirable fermion mass matrix structures independently of the equality of Yukawas, possibly imposed by superstring or other unification.
We analyze the CP violation in the semileptonic | ΔS|=1 tau-decays in supersymmetric extensions of the standard model (SM) with R parity violating term. We show that the CP asymmetry of tau-decay is enhanced significantly and the current experimental limits obtained by CLEO collaborations can be easily accommodated. We argue that observing CP violation in semi leptonic tau-decay would be a clear evidence for R-parity violating SUSY extension of the SM.
The Little Higgs model with T-parity (LHT) belongs to the non-minimal flavour violating model. This model has new sources of flavour and CP violation both in quark and leptonic sectors. These new sources of flavour violation originates by the interaction of Standard Model (SM) fermions with heavy gauge bosons and heavy (or mirror) fermions. In this work we will present the impact of the new flavour structure of T-parity models on flavour violations in leptonic sector.
Recent measurements of CP asymmetry in B --> phi K_S appear to be inconsistent with Standard Model expectations. We explore the effect of R-parity-violating SUSY to understand the data.
The presence of R-parity violating interactions may relieve the tension between existing LHC constraints and natural supersymmetry. In this paper we lay down the theoretical framework and explore models of dynamical R-parity violation in which the breaking of R-parity is communicated to the visible sector by heavy messenger fields. We find that R-parity violation is often dominated by non-holomorphic operators that have so far been largely ignored, and might require a modification of the existing searches at the LHC. The dynamical origin implies that the effects of such operators are suppresse…
Non-Standard-Model parity violation may be occurring in LHC collisions. Any such violation would go unseen, however, as searches are for it are not currently performed. One barrier to searches for parity violation is the lack of model-independent methods sensitive to all of its forms. We remove this barrier by demonstrating an effective and model-independent way to search for parity-violating physics at the LHC. The method is data-driven and makes no reference to any particular parity-violating model. Instead, it inspects data to construct sensitive parity-odd event variables (using machine le…
An effective field theory program to analyze and interpret hadronic parity violation in two-, three-, and few-nucleon systems is described. Observables can be parameterized in terms of five low-energy constants, which have to be determined from experimental input. Results for parity-violating observables in the two- and three-nucleon sectors are presented, including a discussion of the relevance of parity-violating three-nucleon interactions.
Hints of violation of lepton flavor universality in semileptonic $B$ decays have prompted a renewed interest in leptoquarks at the low TeV scale. Among the different scenarios suggested, some happen to violate also lepton number, yet not much attention has been paid to the expected size of the associated lepton number violating processes. In this note we examine this issue. We find that there is a single leptoquark scenario compatible with the current size of the anomalies which also violates lepton number. In this scenario (Majorana) neutrino masses are radiatively generated. With the leptoqu…