3,101 research outputs found

    Radiative decay Z_H-> \gamma A_H in the little Higgs model with T-parity

    Full text link
    In the little Higgs model with T-parity (LHTM), the only tree-level kinematically allowed two-body decay of the Z_H boson is Z_H-> A_H H and thus one-loop induced two-body decays may have a significant rate. We study the Z_H-> \gamma A_H decay, which is induced at the one-loop level by a fermion triangle and is interesting as it depends on the mechanism of anomaly cancellation of the model. All the relevant two- and three-body decays of the Z_H gauge boson arising at the tree-level are also calculated. We consider a small region of the parameter space where the scale of the symmetry breaking f is still allowed to be as low as 500 GeV by electroweak precision data. We first analyze the scenario of a Higgs boson with a mass of 120 GeV. We found that the Z_H->\gamma A_H branching ratio can be of the order of a tree-level three-body decay and may be at the reach of detection at the LHC for f close to 500 GeV, but it may be difficult to detect for f=1 TeV. There is also an scenario where the Higgs boson has an intermediate mass such that the Z_H-> A_H H decay is closed, the Z_H-> \gamma A_H gets considerably enhanced and the chances of detection get a large boost.Comment: 19 pages, 9 figures, 2 table

    Magnetization of ferrofluids with dipolar interactions - a Born--Mayer expansion

    Full text link
    For ferrofluids that are described by a system of hard spheres interacting via dipolar forces we evaluate the magnetization as a function of the internal magnetic field with a Born--Mayer technique and an expansion in the dipolar coupling strength. Two different approximations are presented for the magnetization considering different contributions to a series expansion in terms of the volume fraction of the particles and the dipolar coupling strength.Comment: 19 pages, 11 figures submitted to PR

    Development of Coleomegilla maculata De Geer (Coleoptera: coccinellidae) with prey and artificial diet.

    Get PDF
    Coleomegilla maculata De Geer (Coleoptera: Coccinellidae) is an important predator and has the potential to be used as a biological control agent of insect pests of maize (Zea mays L.) and sorghum [Sorghum bicolor (L.) Moench]. This study aimed to evaluate the development of C. maculata larvae fed eggs Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) alone or associated with artificial diet, eggs of Spodoptera frugiperda (J. E. Smith) (Lepidoptera: Noctuidae) and nymphs of Schizaphis graminum (Rondani) (Hemiptera: Aphididae). The experiment was conducted in a complete randomized design with four replications, each with 10 larvae of C. maculata in an acclimatized room (25 ± 1 ÂșC, 70 ± 10% RH and 12 hours photophase). The duration of the stages of C. maculata was similar in all treatments, except for one that used nymphs of S. graminum, resulting in a shorter period for the larval stage. The viability of larval, prepupal and pupal stages and larval to adult C. maculata was high and similar in all treatments. No effect of diets on the weight of C. maculata adults occurred, except for the heavier insects fed on eggs of A. kuehniella, whose males and females weighed 9.8 ± 0.3 mg and 13.3 ± 0.5 mg, respectively

    Validity of self-reported weight: a study of urban brazilian adults

    Get PDF
    Para avaliar a validade do peso auto-referido em inquĂ©ritos de prevalĂȘncia de obesidade, o mesmo foi comparado com o peso medido de 659 adultos, residentes em Porto Alegre, RS, Brasil, em 1986-87. Ambos os pesos foram obtidos por entrevistador, na casa do participante, na mesma ocasiĂŁo. A mĂ©dia das diferenças entre peso auto-referido e peso medido foi pequena (-0,06 +/-3,16 kg; mĂ©dia +/- desvio padrĂŁo) e a correlação entre eles alta (r=0,97). Sessenta e dois por cento dos participantes referiram seu peso com erro < 2 kg, 87% com erro menor do que 4 kg e 95% com erro < 6 kg. IndivĂ­duos de baixo peso hiperestimaram seu peso, o oposto ocorrendo com indivĂ­duos obesos (p; 30) por peso referido, foi de 10% e a por peso medido, de 11%. Concluindo, a validade do peso auto-referido Ă© aceitĂĄvel para inquĂ©ritos de prevalĂȘncia realizados em contextos similares.In order to evaluate the validity of self-reported weight for use in obesity prevalence surveys, self-reported weight was compared to measured weight for 659 adults living in the Porto Alegre county, RS Brazil in 1986-87, both weights being obtained by a technician in the individual's home on the same visit. The mean difference between self-reported and measured weight was small (-0.06 +/- 3.16 kg; mean +/- standard deviation), and the correlation between reported and measured weight was high (r=0.97). Sixty-two percent of participants reported their weight with an error of < 2 kg, 87% with an error of < 4 kg, and 95% with an error of < 6 kg. Underweight individuals overestimated their weight, while obese individuals underestimated theirs (p; 30) by reported weight was 10%, by measured weight 11%. Thus, the validity of reported weight is acceptable for surveys of the prevalence of ponderosity in similar settings
    • 

    corecore