Addendum to: Search for anomalous top-gluon couplings at LHC revisited

In our latest paper "Search for anomalous top-gluon couplings at LHC revisited" in Eur. Phys. J. C65 (2010), 127-135 (arXiv:0910.3049 [hep-ph]), we studied possible effects of nonstandard top-gluon couplings through the chromoelectric and chromomagnetic moments of the top quark using the total cross section of ppbar/pp --> ttbar X at Tevatron/LHC. There we pointed out that LHC data could give a stronger constraint on those two parameters, which would be hard to obtain from Tevatron data alone. We show here the first CMS measurement of this cross section actually makes it possible.Comment: 5 pages, 1 figure, LaTeX2e, Final version (to appear in Eur. Phys. C

Resultados y complicaciones en alargamientos óseos con alargadores uniplanares

Se realizaron 186 procedimientos en 167 pacientes con discrepancia en la longitud de las extremidades, realizando osteotomías metafisarias y metadiafisiarias proximales o distales. El ritmo de distracción fue 1 mm por día, iniciando al décimo día postoperatorio, con 114 fémures y 69 tibias, 1 húmero, 1 cúbito y 1 peroné. El promedio de alargamiento de 54,4 mm y un porcentaje de alargamiento del 15,9%. El índice de consolidación fue de 42,8 días/cm para fémur y 50,3 días/cm para tibia. La etiología se dividió en grupos que comprendieron: secuelas de poliomielitis, 33,4%; congénitos, 22,5%; infecciosos, 11,4%; estatura corta, 10,5%; secuelas postraumáticas, 7%; displasias óseas, 7%; displasia del desarrollo de la cadera, 6,1%, y metabólicas, 2,6%. Las complicaciones se dividieron en 4 grupos, encontrando que los grupos que mayores complicaciones presentaron fueron el de pacientes con secuelas de poliomielitis y el de problemas congénitos. En nuestro estudio la complicación más frecuente encontrada fue la de contractura, seguida de infecciones del trayecto de los clavos.We performed 186 procedures in 167 patients with leg length discrepancy. Proximal and distal methaphyseal corticotomy was utilized. The rate of distraction was 1 mm per day. The distraction started 10 days postop. We treated 114 femora and 69 tibiae, one humerus, one ulna and one fibula. The average of lengthening was 54.4 mm and 15.9 percent of lengthening for the bone. The healing index was 46.5 days/cm with 42.8 days/cm for femur and 50.3 days/cm for tibiae. The etiology was divided in groups: poliomyelitis sequelae, 33.4%; congenital, 22.5%; infections, 11.4%; short stature, 10.5%; trauma, 7%; dysplasias, 7%; development dysplasia of the hip, 6.1%; metabolic, 2.6%. The complication was divided in four groups and we found that the major complication was present in the group with poliomyelitis sequelae and congenital problems. In our study, we found that contractures and pin tract infections were the most common complication

Dusty Cometary Globules in W5

We report the discovery of four dusty cometary tails around low mass stars in two young clusters belonging to the W5 star forming region. Fits to the observed emission profiles from 24 micron observations with the Spitzer Space Telescope give tail lifetimes < 30 Myr, but more likely < 5 Myr. This result suggests that the cometary phase is a short lived phenomenon, occurring after photoevaporation by a nearby O star has removed gas from the outer disk of a young low mass star (see also Balog et al. 2006; Balog et al. 2008).Comment: 11 pages, 3 figures. Accepted for publication to ApJ Letter

Lepton distribution as a probe of new physics in production and decay of the t quark and its polarization

We investigate the possibilities of studying new physics in various processes of t-quark production using kinematical distributions of the secondary lepton coming from decay of t quarks. We show that the angular distributions of the secondary lepton are insensitive to the anomalous tbW vertex and hence are pure probes of new physics in a generic process of t-quark production. The energy distribution of the lepton is distinctly affected by anomalous tbW couplings and can be used to analyze them independent of the production process of t quarks. The effects of t polarization on the distributions of the decay lepton are demonstrated for top-pair production process at a gamma-gamma collider mediated by a heavy Higgs boson.Comment: 15 pages, 7 figures, uses axodraw.sty (included), references added. v3 to appear in Journal of High Energy Physics. Incorporates minor changes in the discussion on radiative corrections which do not affect the results. Typo in reference correcte

Collider-independent top quark forward-backward asymmetries: Standard model predictions

We compute, for top quark pair production at the Tevatron and the Large Hadron Collider, the collider-independent forward-backward asymmetries defined by [Aguilar-Saavedra and Juste, Phys. Rev. Lett. 109, 211804 (2012).] in the standard model at next-to-leading order in QCD, including also electromagnetic and weak corrections.The work of J.A.A.S. has been supported by MICINN by projects FPA2006-05294 and FPA2010-17915, Junta de Andalucía (FQM 101, FQM 03048 and FQM 6552) and Fundação para a Ciência e Tecnologia (FCT) project CERN/FP/123619/2011. The work of W.B. was supported by DFG, SFB TR9 and that of Z.G. Si by NSFC and by Natural Science Foundation of Shandong Province

Faddeev-Merkuriev equations for resonances in three-body Coulombic systems

We reconsider the homogeneous Faddeev-Merkuriev integral equations for three-body Coulombic systems with attractive Coulomb interactions and point out that the resonant solutions are contaminated with spurious resonances. The spurious solutions are related to the splitting of the attractive Coulomb potential into short- and long-range parts, which is inherent in the approach, but arbitrary to some extent. By varying the parameters of the splitting the spurious solutions can easily be ruled out. We solve the integral equations by using the Coulomb-Sturmian separable expansion approach. This solution method provides an exact description of the threshold phenomena. We have found several new S-wave resonances in the e- e+ e- system in the vicinity of thresholds.Comment: LaTeX with elsart.sty 13 pages, 5 figure

Top-quark FCNC Productions at LHC in Topcolor-assisted Technicolor Model

We evaluate the top-quark FCNC productions induced by the topcolor assisted technicolor (TC2) model at the LHC. These productions proceed respectively through the parton-level processes g g -> t c_bar, c g->t, c g -> t g, c g -> t Z and c g -> t \gamma. We show the dependence of the production rates on the relevant TC2 parameters and compare the results with the predictions in the minimal supersymmetric model. We find that for each channel the TC2 model predicts a much larger production rate than the supersymmetric model. All these rare productions in the TC2 model can be enhanced above the 3-sigma sensitivity of the LHC. Since in the minimal supersymmetric model only c g -> t is slightly larger than the corresponding LHC sensitivity, the observation of these processes will favor the TC2 model over the supersymmetric model. In case of unobservation, the LHC can set meaningful constraints on the TC2 parameters.Comment: 5 pages, 4 fig

Probing the CP nature of the Higgs boson at linear colliders with tau spin correlations; the case of mixed scalar--pseudoscalar couplings

The prospects for the measurement of the pseudoscalar admixture in the h-tau-tau coupling to a Standard Model Higgs boson of 120 GeV mass are discussed in a quantitative manner e+ e- collisions of 350 GeV centre-of-mass energy. Specific angular distributions in the h --> tau tau; tau --> rho nu decay chain can be used to probe mixing angles of scalar--pseudoscalar h-tau-tau couplings. In the discussion of the feasibility of the method, assumptions on the properties of a future detector for an e+ e- linear collider such as TESLA are used. The Standard Model Higgsstrahlung production process is taken as an example. For the expected performance of a typical Linear Collider set-up, the sensitivity of a measurement of the scalar--pseudoscalar mixing angle turned out to be 6 degree. It will be straightforward to apply our results to estimate the sensitivity of a measurement, in cases another scenario of the Higgs boson sector (Standard Model or not) is chosen by nature. The experimental error of the method is expected to be limited by the statistics.Comment: 10 pages, 7 figures, LaTeX. Corrections of published version include

The Inverse Scattering Method, Lie-Backlund Transformations and Solitons for Low-energy Effective Field Equations of 5D String Theory

In the framework of the 5D low-energy effective field theory of the heterotic string with no vector fields excited, we combine two non-linear methods in order to construct a solitonic field configuration. We first apply the inverse scattering method on a trivial vacuum solution and obtain an stationary axisymmetric two-soliton configuration consisting of a massless gravitational field coupled to a non-trivial chargeless dilaton and to an axion field endowed with charge. The implementation of this method was done following a scheme previously proposed by Yurova. We also show that within this scheme, is not possible to get massive gravitational solitons at all. We then apply a non-linear Lie-Backlund matrix transformation of Ehlers type on this massless solution and get a massive rotating axisymmetric gravitational soliton coupled to axion and dilaton fields endowed with charges. We study as well some physical properties of the constructed massless and massive solitons and discuss on the effect of the generalized solution generating technique on the seed solution and its further generalizations.Comment: 17 pages in latex, changed title, improved text, added reference

Is the Cabibbo-Kobayashi-Maskawa Matrix Symmetric at the GUT Scale?

By use of the one-loop renormalization group equations and current experimental data, we study the off-diagonal asymmetries of the Cabibbo-Kobayashi-Maskawa (CKM) matrix at the GUT scale in the framework of the standard model as well as its two Higgs and supersymmetric extensions. It is concluded that the possibility of a symmetric CKM matrix at the GUT scale has almost been ruled out.Comment: Latex 6 pages plus PS 2 pages. This tiny work would not have been put into this archive if I had not noticed an interesting work by P. Kielanowski et al (hep-ph/9703292), whose conclusion seems to be opposite to mine. (Accepted for publication in J. Phys. G