Search Results - "Shields, G.A."

The black hole mass–galaxy bulge relationship for QSOs in the SDSS DR3 by Salviander, S., Shields, G.A., Gebhardt, K., Bonning, E.W.

“…We investigate the relationship between black hole mass, MBH, and host galaxy velocity dispersion, σ∗, for QSOs in Data Release 3 of the Sloan Digital Sky…”
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Reassessing classic evidence for warm-based Cryogenian ice on the western Laurentian margin: The “striated pavement” of the Mineral Fork Formation, USA by Vandyk, T.M., Kettler, C., Davies, B.J., Shields, G.A., Candy, I., Le Heron, D.P.

“…•Only uncontested Cryogenian pavement of N. America reinterpreted as non-glacial.•Previously presumed deep glacial incision now as easily explained by fluvial…”
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Temperate glaciation on a Snowball Earth: Glaciological and palaeogeographic insights from the Cryogenian Yuermeinak Formation of NW China by Vandyk, T.M., Wu, G., Davies, B.J., Xiao, Y., Li, M., Shields, G.A., Le Heron, D.P.

“…•Sedimentology, geomorphology, detrital zircon data from Cryogenian of NW Tarim Craton.•Marinoan subglacial striated surface overlain by subglacial and…”
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Termination of Cryogenian ironstone deposition by deep ocean euxinia by Wu, C., Yang, T., Shields, G.A., Bian, X., Gao, B., Ye, H., Li, W.

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Phosphorites as tracers of 2.0Gyr old ocean chemistry and oxygenation by Goldberg, T., Shields, G.A.

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Compilation and time-series analysis of a marine carbonate δ18O, δ13C, 87Sr/86Sr and δ34S database through Earth history by Prokoph, A., Shields, G.A., Veizer, J.

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Compilation and time-series analysis of a marine carbonate δ 18O, δ 13C, 87Sr/ 86Sr and δ 34S database through Earth history by Prokoph, A., Shields, G.A., Veizer, J.

“…The Sr, S, O and C isotope database of marine carbonates contains over 55,000 published isotope values of low-Mg calcite from diagenetically little altered…”
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A major sulphur isotope event at c. 510 Ma: a possible anoxia-extinction-volcanism connection during the Early-Middle Cambrian transition? by Hough, M.L., Shields, G.A., Evins, L.Z., Strauss, H., Henderson, R.A., Mackenzie, S.

“…A new approach to constraining seawater δ34S and sulphate concentration using francolite‐bound sulphate reveals an abrupt increase in δ34S to +50‰ around the…”
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Phosphorites as tracers of 2.0 Gyr old ocean chemistry and oxygenation by Goldberg, T., Shields, G.A.

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Barite-bearing cap dolostones of the Taoudéni Basin, northwest Africa: Sedimentary and isotopic evidence for methane seapage after a Neoproterozoic glaciation by Shields, G.A., Deynoux, M., Strauss, H., Paquet, H., Nahon, D.

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Evolution of the black hole – Bulge relationship in QSOs by Shields, G.A., Salviander, S., Bonning, E.W.

“…QSOs allow study of the evolution of the relationship between black holes in galactic nuclei and their host galaxies. The black hole mass MBH can be derived…”
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High-resolution strontium isotope stratigraphy across the Cambrian-Ordovician transition by Ebneth, S, Shields, G.A, Veizer, J, Miller, J.F, Shergold, J.H

“…We have analyzed 214 fossil apatite samples from nine stratigraphic sections worldwide that cover the lower Cambrian to lower Ordovician for their strontium…”
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MODELS OF H II REGIONS by SHIELDS, GREGORY A.

“…Models of H II regions provide ionization corrections for abundance determinations and estimates of the ionizing star temperature T* and of the nebular…”
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THEORY OF ACTIVE GALACTIC NUCLEI by SHIELDS, GREGORY A.

“…The involvement of accretion disks around supermassive black holes in the theory of active galactic nuclei (AGN) is discussed. The physics of thin and thick…”
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GAS-PHASE ABUNDANCES OF REFRACTORY ELEMENTS IN PLANETARY NEBULAE: A HOT-WIND MODEL by SHIELDS, G. A.

“…Planetary nebulae (PN) characteristically show large gas-phase depletions of some refractory elements, [Fe/H] ≃ [Ca/H] ≃ — 1.5. In contrast, the gas-phase…”
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THE SPECTRAL ENERGY DISTRIBUTION OF NGC 1275 by SHIELDS, G. A., OKE, J. B.

“…An analysis of absolute spectral energy distributions for NGC 1275 (Per A) covering the wavelength interval λλ3300-10,800 is presented. The data are consistent…”
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Line emission from charge transfer with atomic hydrogen at thermal energies by SHIELDS, G. A, DALGARNO, A, STERNBERG, A

“…A list of emission lines of ions of C,N,O, and Ne which are predicted to appear as a result of low-energy charge transfer and which may be useful as diagnostic…”
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21 cm and 18 cm Observations of the Cygnus X-3 Radio Outburst by SHAFFER, D. B, SHIELDS, G. A, SCHUPLER, B

“…WE have observed the outburst of Cyg X-3 using the Owens Valley Radio Observatory (OVRO) interferometer at 21 cm, and (after technical difficulties halted…”
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