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We investigate a perturbative N=4 sector coupled to the MSSM and show that it allows for a stable vacuum correctly breaking the electroweak symmetry. The particle spectrum of the MSSM is enriched by several new particles stemming out from the new N=4 sector of the theory and a new lepton doublet required to cancel global and gauge anomalies of the theory. Even if the conformal invariance of the N=4 sector is explicitly broken a nontrivial UV behavior of the coupling constants is possible: by studying the renormalization group equations at two loops we find that the Yukawa couplings of the heavy fermionic states flow to a common fixed point at a scale of a few TeVs. The parameter space of the new theory is reduced imposing naturalness of the couplings and soft supersymmetry breaking masses perturbativity of the model at the EW scale as well as phenomenological constraints. Our preliminary results on the spectrum of the theory suggest that the LHC can rule out a significant portion of the parameter space of this model. © 2011 Elsevier B.V.

We extend the results of [arXiv:1006.0207 [hep-lat]] by computing the S-parameter at two loops in the perturbative region of the conformal window. Consistently using the expression for the location of the infra-red fixed point at the two-loop order we express the S-parameter in terms of the number of flavors, colors and matter representation. We show that S, normalized to the number of flavors, increases as we decrease the number of flavors. Our findings support the conjecture presented in [arXiv:1006.0207 [hep-lat]] according to which the normalized value of the S-parameter at the upper end of the conformal window constitutes the lower bound across the entire phase diagram for the given underlying asymptotically free gauge theory. We also show that the non-trivial dependence on the number of flavors merges naturally with the non-perturbative estimate of the S-parameter close to the lower end of the conformal window obtained using gauge duality [arXiv:1007.0254 [hep-ph]]. Our results are natural benchmarks for lattice computations of the S-parameter for vector-like gauge theories., Comment: Version to match the one published in Phys. Lett. B. The file is prepared in the 2-columns RevTeX format has 9 pages, 4 figures and one table

Typhlodromus phialatus and T. exhilaratus are morphologically close species. Their differentiation is based on the shape of the insemination apparatus and on idiosomal setae length. However, the setae length values are often intermediate between these two species and do not allow accurate identification. Furthermore, the handful of differences in insemination apparatus shape are also questionable as a means of differentiation. Synonymy between these species has thus been questioned. Three experiments were carried out. Idiosomal seta length measurements, molecular tests and cross experiments were conducted for three populations, identified as T. exhilaratus and T. phialatus according to the shape of their insemination apparatus. The results show that the variation range of seta lengths is great and that these criteria do not allow accurate separation of these populations into two species. However, molecular tests show a species-level nucleotide differentiation between them. Cross experiments confirm this result, showing complete reproduction incompatibility between the mites bearing different insemination apparatus shapes. Therefore, T. exhilaratus and T. phialatus could be considered to be two valid species and the insemination apparatus could be considered as a pertinent diagnostic criterion at the specific level.

Near conformal dynamics is employed in different extensions of the standard model of particle interactions as well as in cosmology. Many of its interesting properties are either conjectured or determined using model computations. We introduce a relevant four dimensional gauge theory template allowing us to investigate such dynamics perturbatively. The gauge theory we consider is quantum chromodynamics with the addition of a meson-like scalar degree of freedom as well as an adjoint Weyl fermion. At the two-loop level, and in the Veneziano limit, we firmly establish the existence of several fixed points of which one is all directions stable in the infrared. An interesting feature of the model is that this fixed point is lost, within the perturbatively trustable regime, by merging with another fixed point when varying the number of quark flavors. We show the emergence of the Miransky scaling and determine its properties. We are also able to determine the walking region of the theory which turns out to be, at large number of colors, about 12% of the conformal window. Furthermore, we determine highly relevant quantities for near conformal dynamics such as the anomalous dimension of the fermion masses., Comment: 17 pages, 8 figures

We provide a complete extension of Minimal Walking Technicolor able to account for the standard model fermion masses. The model is supersymmetric at energies greater or equal to the technicolor compositeness scale. We integrate out, at the supersymmetry breaking scale, the elementary Higgses. We use the resulting four-fermion operators to derive the low energy effective theory. We then determine the associated tree-level vacuum and low energy spectrum properties. Furthermore we investigate the phenomenological viability of the model by comparing its predictions with electroweak precision tests and experimental bounds on the mass spectrum. We then turn to the composite Higgs phenomenology at the LHC and show that current data are already constraining the parameter space of the model., Comment: 43 pages, 13 figures. Version published on NPB. Typos corrected, results unchanged

We provide a pedagogical introduction to extensions of the Standard Model in which the Higgs is composite. These extensions are known as models of dynamical electroweak symmetry breaking or, in brief, Technicolor. Material covered includes: motivations for Technicolor, the construction of underlying gauge theories leading to minimal models of Technicolor, the comparison with electroweak precision data, the low energy effective theory, the spectrum of the states common to most of the Technicolor models, the decays of the composite particles and the experimental signals at the Large Hadron Collider. The level of the presentation is aimed at readers familiar with the Standard Model but who have little or no prior exposure to Technicolor. Several extensions of the Standard Model featuring a composite Higgs can be reduced to the effective Lagrangian introduced in the text. We establish the relevant experimental benchmarks for Vanilla, Running, Walking, and Custodial Technicolor, and a natural fourth family of leptons, by laying out the framework to discover these models at the Large Hadron Collider., LaTeX, 102 pages. Version to match the published version

We introduce novel extensions of the Standard Model featuring a supersymmetric technicolor sector. First we consider N = 4 Super Yang–Mills which breaks to N = 1 via the electroweak (EW) interactions and coupling to the MSSM. This is a well defined, economical and calculable extension of the SM involving the smallest number of fields. It constitutes an explicit example of a natural super-symmetric conformal extension of the Standard Model featuring a well defined connection to string theory. It allows us to interpolate, depending on how we break the underlying supersymmetry, between unparticle physics and Minimal Walking Technicolor. As a second alternative we consider other N = 1 extensions of the Minimal Walking Technicolor model. The new models allow all the standard model matter fields to acquire a mass.

Laboratory trials were carried out to evaluate the toxicity and the influence of a commercial mixture of vegetal, essential oils, and potassium salts of fatty acids (Acaridoil 13SL) on the population growth rate (r(i)--instantaneous rate of increase) of two mite species, the phytophagous Tetranychus urticae Koch and the predator Phytoseiulus persimilis Athias-Henriot. A residue of 1.3 mg/cm(2) of pesticide solution was harmless for Ph. persimilis eggs, while a moderate mortality of eggs and of larvae from treated eggs of T. urticae, was observed (53.8%). The pesticide also caused a delay in the postembryonic development of the tetranychid. Moreover, 83.4% mortality was reported for treated females tetranychids and only 24.0% for Ph. persimilis females. The pesticide influenced negatively the population growth of T. urticae which showed a very low rate of increase (r(i)=0.07), compared to that obtained in the control (r(i)=0.68). The pesticide did not affect negatively the reproductive potential of Ph. persimilis (r(i)=0.54 and r(i)=0.57 for test and control, respectively). These results suggest a considerable acaricidal activity of potassium salts of fatty acids and caraway oil on T. urticae and a good selectivity on Ph. persimilis.

Surveys of phytoseiid mites were carried out in three lemon orchards in Sicily. The three orchards had different farm management and different environmental conditions: A) traditionally farm managed; B) organic farm managed; C) in state of neglect. The aim was to determine the specific composition of the above different types of orchards and to compare their population dynamics in order to obtain information on the influence of the different agricultural practices on the phytoseiid fauna. After two years of weekly samplings it can be assessed that no substancial differences were found in the phytoseiid specific composition among the three types of orchards. On the other hand, differences, sometimes remarkable ones, were found as far as concerns the role of the various species in the three orchards and in the various seasons. Iphiseius degenerans Berlese, Amblyseius andersoni (Chant) and Euseius stipulatus (Athias-Henriot) were present in the three orchards, Typhlodromus cryptus Athias-Henriot was found in A and B orchards, while Cydnodromus californicus (McGregor) was found only in orchard C. In orchard A the dominant species was A. andersoni (48%), followed by I. degenerans (44%) and E. stipulatus (7%). The first and the last species were present esclusively in the winter-spring period, while I. degenerans was the only species present in summer. On the contrary, in orchard B, the dominant species was I. degenerans (69%), present in all seasons, followed by A. andersoni and E. stipulatus (16 and 14% respectively). These latter ones were found exclusively in spring. In orchard C the dominant species was E. stipulatus (58%) mainly present in the hot seasons, followed by I. degenerans (38%) and A. andersoni (3%).

Surveys of phytoseiid mites were carried out in three lemon orchards in Sicily. The three orchards had different farm management and different environmental conditions: A) traditionally farm managed; B) organic farm managed; C) in state of neglect. The aim was to determine the specific composition of the above different types of orchards and to compare their population dynamics in order to obtain information on the influence of the different agricultural practices on the phytoseiid fauna. After two years of weekly samplings it can be assessed that no substancial differences were found in the phytoseiid specific composition among the three types of orchards. On the other hand, differences, sometimes remarkable ones, were found as far as concerns the role of the various species in the three orchards and in the various seasons. Iphiseius degenerans Berlese, Amblyseius andersoni (Chant) and Euseius stipulatus (Athias-Henriot) were present in the three orchards, Typhlodromus cryptus Athias-Henriot was found in A and B orchards, while Cydnodromus californicus (McGregor) was found only in orchard C. In orchard A the dominant species was A. andersoni (48%), followed by I. degenerans (44%) and E. stipulatus (7%). The first and the last species were present esclusively in the winter-spring period, while I. degenerans was the only species present in summer. On the contrary, in orchard B, the dominant species was I. degenerans (69%), present in all seasons, followed by A. andersoni and E. stipulatus (16 and 14% respectively). These latter ones were found exclusively in spring. In orchard C the dominant species was E. stipulatus (58%) mainly present in the hot seasons, followed by I. degenerans (38%) and A. andersoni (3%).