48 research outputs found
Symmetry restoration at high-temperature in two-color and two-flavor lattice gauge theories
We consider the SU(2) gauge theory with Nf=2 flavors of Dirac fundamental fermions. We study the high-temperature behavior of the spectra of mesons, discretizing the theory on anisotropic lattices, and measuring the two-point correlation functions in the temporal direction as well as screening masses in various channels. We identify the (pseudo-)critical temperature as the temperature at which the susceptibility associated with the Polyakov loop has a maximum. At high temperature both the spin-1 and spin-0 sectors of the light meson spectra exhibit enhanced symmetry properties, indicating the restoration of both the global SU(4) and the axial U(1)A symmetries of the model
Probing strongly interacting W's at the ILC with polarized beams
We study the possibility of fingerprinting a strongly interacting boson
sector which is consistent with present day LHC searches at the ILC with
longitudinal as well as transversely polarized electron and positron beams. We
account for the final state interaction using a suitable Omn\`es formalism in
terms of a plausible resonance description, and carry out thorough analyses of
cross sections, asymmetries and angular distributions of the . We carry
out a comparison with other extensions of the Standard Model, where heavy
additional bosons arise naturally. We also consider the effect of the
strong final state interaction on a correlation that depends on
, where the are the azimuthal angles of decay
leptons, and find that it is a useful discriminant.Comment: 25 pages latex using JHEP style files, 14 figures; v2 is a slightly
expanded version of v1, reference added, discussions improved, some figures
have been changed; corresponds to version accepted for publication in JHE
Functional Dicer Is Necessary for Appropriate Specification of Radial Glia during Early Development of Mouse Telencephalon
Early telencephalic development involves transformation of neuroepithelial stem cells into radial glia, which are themselves neuronal progenitors, around the time when the tissue begins to generate postmitotic neurons. To achieve this transformation, radial precursors express a specific combination of proteins. We investigate the hypothesis that micro RNAs regulate the ability of the early telencephalic progenitors to establish radial glia. We ablate functional Dicer, which is required for the generation of mature micro RNAs, by conditionally mutating the Dicer1 gene in the early embryonic telencephalon and analyse the molecular specification of radial glia as well as their progeny, namely postmitotic neurons and basal progenitors. Conditional mutation of Dicer1 from the telencephalon at around embryonic day 8 does not prevent morphological development of radial glia, but their expression of Nestin, Sox9, and ErbB2 is abnormally low. The population of basal progenitors, which are generated by the radial glia, is disorganised and expanded in Dicer1-/- dorsal telencephalon. While the proportion of cells expressing markers of postmitotic neurons is unchanged, their laminar organisation in the telencephalic wall is disrupted suggesting a defect in radial glial guided migration. We found that the laminar disruption could not be accounted for by a reduction of the population of Cajal Retzius neurons. Together, our data suggest novel roles for micro RNAs during early development of progenitor cells in the embryonic telencephalon
QCD and strongly coupled gauge theories : challenges and perspectives
We highlight the progress, current status, and open challenges of QCD-driven physics, in theory and in experiment. We discuss how the strong interaction is intimately connected to a broad sweep of physical problems, in settings ranging from astrophysics and cosmology to strongly coupled, complex systems in particle and condensed-matter physics, as well as to searches for physics beyond the Standard Model. We also discuss how success in describing the strong interaction impacts other fields, and, in turn, how such subjects can impact studies of the strong interaction. In the course of the work we offer a perspective on the many research streams which flow into and out of QCD, as well as a vision for future developments.Peer reviewe