8,713 research outputs found

    Opioid Multidistrict Litigation Secrecy

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    The XRF080109-SN2008D and a decade of GRB-Jet-SN connection

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    Last and nearest GRB-XRF 080109 has been an exceptional lesson on GRB nature. After a decade (since 25 April 08) we know that Supernovae may often contain a Jet. Its persistent activity may shine on axis as a GRBs. Such a persistent, thin beamed gamma jet may be powered by either a BH (Black Holes) or Pulsars. Late stages of these jets may loose the SN traces and appear as a short GRB or a long orphan GRB (depending on jet angular velocity and view angle). XRF are peripherical viewing of the jets. These precessing and spinning gamma jet are originated by Inverse Compton and-or Synchrotron Radiation at pulsars or micro-quasars sources, by ultra-relativistic electrons. These Jets are most powerful at Supernova birth, blazing, once on axis, to us and flashing GRB detector. The trembling of the thin jet explains naturally the observed erratic multi-explosive structure of different GRBs. The jets are precessing (by binary companion or inner disk asymmetry) and decaying by power on time scales of few hours, but they keep staying inside the observer cone view only a few seconds duration times (GRB); the jet is thinner in gamma and wider in X band. This explain the wider and longer X GRB afterglow duration and the rare presence of X-ray precursors.Comment: 11 pages, 12 figure

    Vacuum solutions with nontrivial boundaries for the Einstein-Gauss-Bonnet theory

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    The classification of certain class of static solutions for the Einstein-Gauss-Bonnet theory in vacuum is presented. The spacelike section of the class of metrics under consideration is a warped product of the real line with a nontrivial base manifold. For arbitrary values of the Gauss-Bonnet coupling, the base manifold must be Einstein with an additional scalar restriction. The geometry of the boundary can be relaxed only when the Gauss-Bonnet coupling is related with the cosmological and Newton constants, so that the theory admits a unique maximally symmetric solution. This additional freedom in the boundary metric allows the existence of three main branches of geometries in the bulk, containing new black holes and wormholes in vacuum.Comment: Prepared for the proceedings of the 7th Alexander Friedmann International Seminar on Gravitation and Cosmology, July 2008, Joao Pessoa, Brasil. 4 pages, References adde

    The connection between the peaks in velocity dispersion and star-forming clumps of turbulent galaxies

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    We present Keck/OSIRIS adaptive optics observations with 150-400 pc spatial sampling of 7 turbulent, clumpy disc galaxies from the DYNAMO sample (0.07<z<0.20.07<z<0.2). DYNAMO galaxies have previously been shown to be well matched in properties to main sequence galaxies at z1.5z\sim1.5. Integral field spectroscopy observations using adaptive optics are subject to a number of systematics including a variable PSF and spatial sampling, which we account for in our analysis. We present gas velocity dispersion maps corrected for these effects, and confirm that DYNAMO galaxies do have high gas velocity dispersion (σ=4080\sigma=40-80\kms), even at high spatial sampling. We find statistically significant structure in 6 out of 7 galaxies. The most common distance between the peaks in velocity dispersion and emission line peaks is 0.5\sim0.5~kpc, we note this is very similar to the average size of a clump measured with HST Hα\alpha maps. This could suggest that the peaks in velocity dispersion in clumpy galaxies likely arise due to some interaction between the clump and the surrounding ISM of the galaxy, though our observations cannot distinguish between outflows, inflows or velocity shear. Observations covering a wider area of the galaxies will be needed to confirm this result.Comment: Accepted for publication in MNRA

    Exact Hairy Black Holes and their Modification to the Universal Law of Gravitation

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    In this paper two things are done. First, it is pointed out the existence of exact asymptotically flat, spherically symmetric black holes when a self interacting, minimally coupled scalar field is the source of the energy momentum of the Einstein equations in four dimensions. The scalar field potential is the recently found to be compatible with the hairy generalization of the Plebanski-Demianski solution of general relativity. This paper describes the spherically symmetric solutions that smoothly connect the Schwarzschild black hole with its hairy counterpart. The geometry and scalar field are everywhere regular except at the usual Schwarzschild like singularity inside the black hole. The scalar field energy momentum tensor satisfies the null energy condition in the static region of the spacetime. The first law holds when the parameters of the scalar field potential are fixed under thermodynamical variation. Secondly, it is shown that an extra, dimensionless parameter, present in the hairy solution, allows to modify the gravitational field of a spherically symmetric black hole in a remarkable way. When the dimensionless parameter is increased, the scalar field generates a flat gravitational potential, that however asymptotically matches the Schwarzschild gravitational field. Finally, it is shown that a positive cosmological constant can render the scalar field potential convex if the parameters are within a specific rank.Comment: Two new references, 10 pages, 2 figure

    UHECR narrow clustering correlating IceCube through-going muons

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    The recent UHECR events by AUGER and the Telescope Array (TA) suggested that wide clusterings as the North and South, named Hot Spot, are related to near AGNs such as the one in M82 and Cen A. In the same frame since 2008 we assumed that the UHECR are made by light and lightest nuclei to explain the otherwise embarrassing absence of the huge nearby Virgo cluster, absence due to the fragility and the opacity of lightest nuclei by photo-dissociation from Virgo distances. Moreover UHECR map exhibits a few narrow clustering, some near the galactic plane, as toward SS 433 and on the opposite side of the plane at celestial horizons: we tagged them in 2014 suggesting possible near source active also as a UHE neutrino. Indeed since last year, 2015, highest IceCube trough-going muons, UHE up-going neutrino events at hundreds TeV energy, did show (by two cases over three tagged in North sky) the expected overlapping of UHE neutrinos signals with narrow crowding UHECR. New data with higher energy threshold somehow re-confirmed our preliminary proposal; new possible sources appear by a additional correlated UHE-neutrino versus UHE-neutrino and-or with narrow UHECR clustering events. A possible role of relic neutrino mass scattering by ZeV neutrino arised.Comment: 6 pages, 5 figure
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