Longitudinal WW scattering in light of the 'Higgs boson' discovery

WW scattering is dominated at high energies by their longitudinal components, which are the most sensitive to the nature of the electroweak symmetry breaking. Prior to the discovery at the LHC of a Higgs-like particle, unitarization tools were extensively used to show that, in the absence of a light Higgs boson, new resonances resulting from the would-be strongly interacting electroweak sector would appear, and furthermore these techniques would approximately predict their masses, widths, and signal strengths. With the discovery of a Higgs-like particle now firmly established, we reinvestigate these techniques assuming this particle couples exactly as in the standard model (SM), but still being open to the possibility of an extended symmetry breaking sector. While the SM itself is free from problems with perturbative unitarity in the electroweak sector, "anomalous" self-couplings of the vector bosons low-energy remnants of such higher-energy symmetry breaking sectors are easily shown to reintroduce them. We demonstrate how new resonances should still appear in the scattering of electroweak vector bosons after imposing constraints from unitarity, and we discuss their ability to be probed with current and future LHC data

Radiative corrections to WL WL scattering in composite Higgs models

The scattering of longitudinally polarized electroweak bosons is likely to play an important role in the elucidation of the fundamental nature of the electroweak symmetry breaking sector and in determining the Higgs interactions with this sector. In this paper, by making use of the equivalence theorem, we determine the renormalization properties of the electroweak effective theory parameters in a model with generic Higgs couplings to the W and Z bosons. When the couplings between the Higgs and the electroweak gauge bosons deviate from their Standard Model values, additional counterterms of O(p4) in the usual chiral counting are required. We also determine in the same approximation the full radiative corrections to the WLWL→ZLZL process in this type of model. Assuming custodial invariance, all the related processes can be easily derived from this amplitude

Identification of simple sequence repeat markers for sweetpotato weevil resistance

The development of sweetpotato [Ipomoea batatas (L.) Lam] germplasm with resistance to sweetpotato weevil (SPW) requires an understanding of the biochemical and genetic mechanisms of resistance to optimize crop resistance. The African sweetpotato landrace, ‘New Kawogo’, was reported to be moderately resistant to two species of SPW, Cylas puncticollis and Cylas brunneus. Resistance has been associated with the presence of hydroxycinnamic acids esters (HCAs), but the underlying genetic basis remains unknown. To determine the genetic basis of this resistance, a bi-parental sweetpotato population from a cross between the moderately resistant, white-fleshed ‘New Kawogo’ and the highly susceptible, orange-fleshed North American variety ‘Beauregard’ was evaluated for SPW resistance and genotyped with simple sequence repeat (SSR) markers to identify weevil resistance loci. SPW resistance was measured on the basis of field storage root SPW damage severity and total HCA ester concentrations. Moderate broad sense heritability (H2 = 0.49) was observed for weevil resistance in the population. Mean genotype SPW severity scores ranged from 1.0 to 9.0 and 25 progeny exhibited transgressive segregation for SPW resistance. Mean genotype total HCA ester concentrations were significantly different (P < 0.0001). A weak but significant correlation (r = 0.103, P = 0.015) was observed between total HCA ester concentration and SPW severity. A total of five and seven SSR markers were associated with field SPW severity and total HCA ester concentration, respectively. Markers IBS11, IbE5 and IbJ544b showed significant association with both field and HCA-based resistance, representing potential markers for the development of SPW resistant sweetpotato cultivars

Marcadores SNPs associados à resistência a nematoides-das-galhas em população de batata-doce da Embrapa-DF

Este estudo teve como objetivo validar o uso de SNPs para a seleção de caracteres de resistência aos nematoides M. incognita e M. enterolobii em uma população de batata-doce da Embrapa Hortaliças. Amostras foliares de 376 plantas jovens de uma população da Embrapa-DF foram coletadas e enviadas para a empresa Intertek (Suíça), para a realização de genotipagem.SIGM. International Symposium on Genetics and Breeding

The First Decade of Science with Chandra and XMM-Newton

NASA's Chandra X-ray Observatory and ESA's XMM-Newton made their first observations one decade ago. The unprecedented and complementary capabilities of these observatories to detect, image, and measure the energy of cosmic X-rays, achieved less than 50 years after the first detection of an extra-solar X-ray source, represent an increase in sensitivity comparable in going from naked-eye observations to the most powerful optical telescopes over the past 400 years! In this review, we highlight some of the many discoveries made by Chandra and XMM-Newton that have transformed 21st century astronomy and briefly discuss prospects for future research.Comment: 8 pages, 10 figures, published in Natur

Longitudinal WW scattering in light of the 'Higgs boson' discovery

WW scattering is dominated at high energies by their longitudinal components, which are the most sensitive to the nature of the electroweak symmetry breaking. Prior to the discovery at the LHC of a Higgs-like particle, unitarization tools were extensively used to show that, in the absence of a light Higgs boson, new resonances resulting from the would-be strongly interacting electroweak sector would appear, and furthermore these techniques would approximately predict their masses, widths, and signal strengths. With the discovery of a Higgs-like particle now firmly established, we reinvestigate these techniques assuming this particle couples exactly as in the standard model (SM), but still being open to the possibility of an extended symmetry breaking sector. While the SM itself is free from problems with perturbative unitarity in the electroweak sector, "anomalous" self-couplings of the vector bosons low-energy remnants of such higher-energy symmetry breaking sectors are easily shown to reintroduce them. We demonstrate how new resonances should still appear in the scattering of electroweak vector bosons after imposing constraints from unitarity, and we discuss their ability to be probed with current and future LHC data