Graham A Shields

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We examine the black hole mass-galaxy bulge relationship in high-redshift QSOs. Black hole masses are derived from the broad emission lines, and the host galaxy stellar velocity dispersion σ * is estimated from the widths of the radio CO emission lines. At redshifts z > 3, the CO line widths are narrower than expected for the black hole mass, indicating(More)
Effective use of cerium anomalies as a redox proxy in carbonate-dominated marine settingsEffective use of cerium anomalies as a redox proxy in carbonate-dominated marine settings' Chemical Geology, vol 438, pp. 146-General rights Copyright for the publications made accessible via the Edinburgh Research Explorer is retained by the author(s) and / or other(More)
Recent simulations of merging black holes with spin give recoil velocities from gravitational radiation up to several thousand km s −1. A recoiling supermassive black hole can retain the inner part of its accretion disk, providing fuel for a continuing QSO phase lasting millions of years as the hole moves away from the galactic nucleus. One possible(More)
We present measurements of the gas-phase C/O abundance ratio in six H II regions in the spiral galaxies M101 and NGC 2403, based on ultraviolet spectroscopy using the Faint Object Spectrograph on the Hubble Space Telescope. The C/O ratios increase systematically with O/H in both galaxies, from log C/O ≈ −0.8 at log O/H = −4.0 to log C/O ≈ −0.1 at log O/H =(More)
The strontium isotope composition of seawater is strongly influenced on geological time scales by changes in the rates of continental weathering relative to ocean crust alteration. However, the potential of the seawater 87 Sr/ 86 Sr curve to trace globally integrated chemical weathering rates has not been fully realised because ocean 87 Sr/ 86 Sr is also(More)
The quasar SDSS J105041.35+345631.3 (z = 0.272) has broad emission lines blueshifted by 3500 km s −1 relative to the narrow lines and the host galaxy. Such an object may be a candidate for a recoiling supermassive black hole, a binary black hole, a superposition of two objects, or an unusual geometry for the broad emission-line region (BLR). The absence of(More)
The long-term, steady-state marine carbon isotope record reflects changes to the proportional burial rate of organic carbon relative to total carbon on a global scale. For this reason, times of high δ13C are conventionally interpreted to be oxygenation events caused by excess organic burial. Here we show that the carbon isotope mass balance is also(More)
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