57,075 research outputs found

    Singlet Model Interference Effects with High Scale UV Physics

    Get PDF
    One of the simplest extensions of the Standard Model (SM) is the addition of a scalar gauge singlet, S. If S is not forbidden by a symmetry from mixing with the Standard Model Higgs boson, the mixing will generate non-SM rates for Higgs production and decays. In general, there could also be unknown high energy physics that generates additional effective low energy interactions. We show that interference effects between the scalar resonance of the singlet model and the effective field theory (EFT) operators can have significant effects in the Higgs sector. We examine a non-Z2Z_2 symmetric scalar singlet model and demonstrate that a fit to the 125 GeV Higgs boson couplings and to limits on high mass resonances, S, exhibit an interesting structure and possible large cancellations of effects between the resonance contribution and the new EFT interactions, that invalidate conclusions based on the renormalizable singlet model alone.Comment: 18 pages, 7 figures; revised to emphasize the points of general interest for heavy resonance searches at the LH

    A Proactive Approach to Womens Concerns: Womens Longevity Groups and Funds

    Get PDF
    With the exception of ten countries in the world, according to the World Health Organization's 2005 report, women outlive men. In the United States, women outlive men by 5.3 years. Although long life is an advantage, there are major consequences that must be understood and dealt with, especially in these transitional times in the lives of women. Women are still underpaid for comparable positions, uncompensated for their caregiving and kin-keeping activities, including, notably, the rearing of children. Moreover, as is characteristic of both men and women, there is the tendency to defer, if not deny, the issues that confront one as one grows older

    The integral cohomology rings of some p-groups

    Full text link
    We determine the integral cohomology rings of an infinite family of p-groups, for odd primes p, with cyclic derived subgroups. Our method involves embedding the groups in a compact Lie group of dimension one, and was suggested by P H Kropholler and J Huebschmann

    Top Partners and Higgs Boson Production

    Get PDF
    The Higgs boson is produced at the LHC through gluon fusion at roughly the Standard Model rate. New colored fermions, which can contribute to gghgg\rightarrow h, must have vector-like interactions in order not to be in conflict with the experimentally measured rate. We examine the size of the corrections to single and double Higgs production from heavy vector-like fermions in SU(2)LSU(2)_L singlets and doublets and search for regions of parameter space where double Higgs production is enhanced relative to the Standard Model prediction. We compare production rates and distributions for double Higgs production from gluon fusion using an exact calculation, the low energy theorem (LET), where the top quark and the heavy vector-like fermions are taken to be infinitely massive, and an effective theory (EFT) where top mass effects are included exactly and the effects of the heavy fermions are included to O(1/MX2){\cal O}(1/M^2_X). Unlike the LET, the EFT gives an extremely accurate description of the kinematic distributions for double Higgs production.Comment: 37 pages, 11 figures. Minor changes to Figs. 8-1

    T Tauri variability in the context of the beat-frequency model

    Get PDF
    We examine the implications of a beat frequency modulated model of T Tauri accretion. In particular we show that measurements of the variability of accretion generated lines can be used in conjunction with existing photometry to obtain a measurement of the underlying photospheric and disc flux. This provides an independent way of checking spectral energy distribution modelling. In addition, we show how spectroscopy of T Tauri stars can reveal the inclination angle between the magnetic axis and the plane of the disc.Comment: uuencoded compressed postscript. The preprint is also available at http://www.ast.cam.ac.uk/preprint/PrePrint.htm

    Flight parameters and vehicle performance for project fire flight 1, launched april 14, 1964

    Get PDF
    Flight parameters and spacecraft performance for Fire project flight

    Comparison of a grid-based CFD method and vortex dynamics predictions of low Reynolds number cylinder flow

    Get PDF
    Computational fluid dynamics models range from the finite difference type grid-based method to the Lagrangian style vortex cloud simulation technique for solving the Navier-Stokes equations. This paper undertakes a comparison of these two methods for the classical datum bluff body case of flow past a stationary circular cylinder at low Reynolds numbers in the range 10 to 220. Comparisons include time-history, time-mean and root-mean-square values of oscillating drag and lift coefficients, frequency of vortex shedding and related vortex street wake flow patterns. Particularly close agreement was obtained for Strouhal number versus Reynolds number, and good agreement for time-mean value of drag coefficients; comparison was also made with experimental results. Attempts are also made to calculate the skin friction and surface pressure components of the cylinder drag, revealing the significance of skin friction drag within this range and its relative insignificance above a Reynolds number of 220

    Constructing an understanding of mind : the development of children's social understanding within social interaction

    Get PDF
    Theories of children's developing understanding of mind tend to emphasize either individualistic processes of theory formation, maturation, or introspection, or the process of enculturation. However, such theories must be able to account for the accumulating evidence of the role of social interaction in the development of social understanding. We propose an alternative account, according to which the development of children's social understanding occurs within triadic interaction involving the child's experience of the world as well as communicative interaction with others about their experience and beliefs (Chapman 1991; 1999). It is through such triadic interaction that children gradually construct knowledge of the world as well as knowledge of other people. We contend that the extent and nature of the social interaction children experience will influence the development of children's social understanding. Increased opportunity to engage in cooperative social interaction and exposure to talk about mental states should facilitate the development of social understanding. We review evidence suggesting that children's understanding of mind develops gradually in the context of social interaction. Therefore, we need a theory of development in this area that accords a fundamental role to social interaction, yet does not assume that children simply adopt socially available knowledge but rather that children construct an understanding of mind within social interaction
    corecore