Neutrinoless double-beta decay matrix elements in large shell-model spaces with the generator-coordinate method

We use the generator-coordinate method with realistic shell-model interactions to closely approximate full shell-model calculations of the matrix elements for the neutrinoless double-beta decay of $^{48}$Ca, $^{76}$Ge, and $^{82}$Se. We work in one major shell for the first isotope, in the $f_{5/2}pg_{9/2}$ space for the second and third, and finally in two major shells for all three. Our coordinates include not only the usual axial deformation parameter $\beta$, but also the triaxiality angle $\gamma$ and neutron-proton pairing amplitudes. In the smaller model spaces our matrix elements agree well with those of full shell-model diagonalization, suggesting that our Hamiltonian-based GCM captures most of the important valence-space correlations. In two major shells, where exact diagonalization is not currently possible, our matrix elements are only slightly different from those in a single shell.Comment: 8 pages, 7 figure

Highly extinguished emission line outflows in the young radio source PKS 1345+12

(Abridged) We present new, intermediate resolution spectra (~4A) of the compact radio source PKS 1345+12. Our spectra clearly show extended line emission (~20kpc) consistent with the asymmetric halo of diffuse emission observed in optical and infra-red images. In the nucleus we observe complex emission line profiles requiring 3 Gaussian components (narrow, intermediate and broad). The broadest component (FWHM ~2000 km/s) is blue shifted by ~2000 km/s with respect to the galaxy halo and HI absorption. We interpret this as material in outflow. We find evidence for high reddening and measure E(B-V)>0.92 for the broadest component. From [S II]6716,6731 we estimate electron densities of n_e5300 cm^{-3} and n_{e}>4200 cm^{-3} for the regions emitting the narrow, intermediate and broad components respectively. We calculate a total mass of line emitting gas of M_{gas}<10^6 solar masses. Not all emission line profiles can be reproduced by the same model: [O I]6300,6363 and [S II] require separate, unique models. We argue that PKS 1345+12 is a young radio source whose nuclear regions are enshrouded in a dense cocoon of gas and dust. The radio jets are expanding, sweeping material out of the nuclear regions. Emission originates from three kinematically distinct regions though gradients (e.g. density, ionisation potential, acceleration) must exist across the regions responsible for the emission of the intermediate and broad components.Comment: Accepted for publication in MNRAS, 13 pages, 8 postscript figure

Abundance and distribution of larval fishes and shrimps in the Laguna Madre, Texas : a hypersaline lagoon

To Texas Water Development BoardContract nos. IAC (88-89)1636 and (90-91)0751October 1990Tidal inlets connecting the Gulf of Mexico with estuarine waters are widely spaced and relatively narrow along the Texas coast. These inlets provide the sole route for ingress of larvae to the estuary for estuarine-dependent marine species and the egress of juveniles and sub-adults of these species back to the ocean. This study was an investigation of the abundance and distribution of ichthyoplankton of selected fishes and shrimps in an area where the opening and maintenance of a new tidal pass has been proposed in the Laguna Madre, a sub-tropical, hypersaline lagoon along the southern Texas coast. Surface and bottom ichthyoplankton samples were taken bimonthly in four zones in the Laguna Madre in areas which were directly influenced by tidal inlets from the Gulf of Mexico and areas isolated from such connections. Seasonal composition of the ichthyoplankton was similar to that reported from other Gulf of Mexico and southeastern United States estuaries with winter catches dominated by offshore spawners and summer catches dominated by inshore and estuarine spawners. The pelagic larvae of three species of estuarine spawners, bay anchovy (Anchoa mitchilli), spotted seatrout (Cynoscion nebulosus), and black drum (Pogonias cromis), were common throughout the Laguna Madre at salinities up to 50°/00. Pelagic larvae of offshore spawners were abundant only in the area near the tidal inlet and only a few individuals were found dispersed throughout the lagoon. The majority of these species are distributed throughout the Laguna Madre as juveniles but the dispersion or advection of these species to areas not closely associated with tidal inlets occurs at development stages older than the pelagic larval stage. These data suggest that opening and maintaining a tidal inlet in the upper Laguna Madre would increase the opportunity for recruitment of larvae of offshore spawners into an area currently unoccupied by these life-history stages.Marine Scienc

The impact of the warm outflow in the young (GPS) radio source & ULIRG PKS 1345+12 (4C 12.50)

(Abridged) We present new deep VLT/FORS optical spectra with intermediate resolution and large wavelength coverage of the GPS radio source and ULIRG PKS1345+12 (4C12.50; z=0.122), taken with the aim of investigating the impact of the nuclear activity on the circumnuclear ISM. PKS1345+12 is a powerful quasar and is also the best studied case of an emission line outflow in a ULIRG. Using the density sensitive transauroral emission lines [S II]4068,4076 and [O II]7318,7319,7330,7331, we pilot a new technique to accurately model the electron density for cases in which it is not possible to use the traditional diagnostic [S II]6716/6731, namely sources with highly broadened complex emission line profiles and/or high (Ne > 10^4 cm^-3) electron densities. We measure electron densities of Ne=2.94x10^3 cm^-3, Ne=1.47x10^4 cm^-3 and Ne=3.16x10^5 cm^-3 for the regions emitting the narrow, broad and very broad components respectively. We calculate a total mass outflow rate of 8 M_sun yr^-1. We estimate the total mass in the warm gas outflow is 8x10^5 M_sun. The total kinetic power in the warm outflow is 3.4x10^42 erg s^-1. We find that only a small fraction (0.13% of Lbol) of the available accretion power is driving the warm outflow, significantly less than currently required by the majority of quasar feedback models (~5-10\% of Lbol), but similar to recent findings by Hopkins et al. (2010) for a two-stage feedback model. The models also predict that AGN outflows will eventually remove the gas from the bulge of the host galaxy. The visible warm outflow in PKS1345+12 is not currently capable of doing so. However, it is entirely possible that much of the outflow is either obscured by a dense and dusty natal cocoon and/or in cooler or hotter phases of the ISM. This result is important not just for studies of young (GPS/CSS) radio sources, but for AGN in general.Comment: Accepted for publication in MNRAS. 11 pages, 4 figure

Gas outflows in radio galaxies

We present a summary of our recent results on gas outflows in radio galaxies. Fast outflows (up to 2000 km/s) have been detected both in ionized and neutral gas. The latter is particularly surprising as it shows that, despite the extremely energetic phenomena occurring near an AGN, some of the outflowing gas remains, or becomes again, neutral. These results are giving new and important insights on the physical conditions of the gaseous medium around an AGN.Comment: To appear in the proceedings of the IAU Symposium #217, Recycling Intergalactic and Interstellar Matter, eds. P.-A. Duc, J. Braine, and E. Brinks, 6 pages. The full paper with high resolution images can be downloaded from http://www.astron.nl/~morganti/Papers/outflows.ps.g

Electronic packaging - A bibliography

Annotated bibliography of literature on electronic packaging for use in designing electronic equipmen