HI and OH absorption in the lensing galaxy of MG J0414+0534

We report the detection of \HI 21-cm absorption in the $z=0.96$ early-type lensing galaxy towards MG J0414+0534 with the Green Bank Telescope. The absorption, with total $N_{\rm HI}=1.6 \times 10^{18} (T_{\rm s}/f) {\rm cm}^{-2}$, is resolved into two strong components, probably due to the two strongest lens components, which are separated by 0.4\arcsec. Unlike the other three lenses which have been detected in \HI, J0414+0534 does not exhibit strong OH absorption, giving a OH/\HI column density ratio of N_{\rm OH}/N_{\rm HI}\lapp10^{-6} (for $T_{\rm s}=100$ K, $T_{\rm x}=10$ K and $f_{\rm HI}=f_{\rm OH}=1$). This underabundance of molecular gas may indicate that the extreme optical--near-IR colour ($V-K=10.26$) along the line-of-sight is not due to the lens. We therefore suggest that despite the strong upper limits on molecular absorption at the quasar redshift, as traced by millimetre lines, the extinction occurs primarily in the quasar host galaxy.Comment: Accepted by MNRAS Letters, 5 (and a bit) pages, 5 figure

ALMA Observations of Circumnuclear Disks in Early Type Galaxies: 12CO(2-1) and Continuum Properties

We present results from an Atacama Large Millimeter/submillimeter Array (ALMA) Cycle 2 program to map CO(2-1) emission in nearby early-type galaxies (ETGs) that host circumnuclear gas disks. We obtained $\sim0.3''-$resolution Band 6 observations of seven ETGs selected on the basis of dust disks in Hubble Space Telescope images. We detect CO emission in five at high signal-to-noise ratio with the remaining two only faintly detected. All CO emission is coincident with the dust and is in dynamically cold rotation. Four ETGs show evidence of rapid central rotation; these are prime candidates for higher-resolution ALMA observations to measure the black hole masses. In this paper we focus on the molecular gas and continuum properties. Total gas masses and H$_2$ column densities for our five CO-bright galaxies are on average $\sim10^8$ $M_\odot$ and $\sim10^{22.5}$ cm$^{-2}$ over the $\sim$kpc-scale disks, and analysis suggests that these disks are stabilized against gravitational fragmentation. The continuum emission of all seven galaxies is dominated by a central, unresolved source, and in five we also detect a spatially extended component. The $\sim$230 GHz nuclear continua are modeled as power laws ranging from $S_\nu \sim \nu^{-0.4}$ to $\nu^{1.6}$ within the observed frequency band. The extended continuum profiles of the two radio-bright (and CO-faint) galaxies are roughly aligned with their radio jet and suggests resolved synchrotron jets. The extended continua of the CO-bright disks are coincident with optically thick dust absorption and have spectral slopes that are consistent with thermal dust emission.Comment: 20 pages, 10 figures; accepted for publication in Ap

Relaxation at late stages in an entropy barrier model for glassy systems

The ground state dynamics of an entropy barrier model proposed recently for describing relaxation of glassy systems is considered. At stages of evolution the dynamics can be described by a simple variant of the Ehrenfest urn model. Analytical expression for the relaxation times from an arbitrary state to the ground state is derived. Upper and lower bounds for the relaxation times as a function of system size are obtained.Comment: 9 pages no figures. to appear in J.Phys. A: Math. and Ge

High-dimensional quantum dynamics of adsorption and desorption of H2_2 at Cu(111)

We performed high-dimensional quantum dynamical calculations of the dissociative adsorption and associative desorption of hydrogen on Cu(111). The potential energy surface (PES) is obtained from density functional theory calculations. Two regimes of dynamics are found, at low energies sticking is determined by the minimum energy barrier, at high energies by the distribution of barrier heights. Experimental results are well-reproduced qualitatively, but some quantitative discrepancies are identified as well.Comment: 4 two column pages, revtex, 4 figures, to appear in Phys. Rev. Let

Elastic and thermodynamic properties of the shape-memory alloy AuZn

The current work reports on the elastic shear moduli, internal friction, and the specific heat of the B2 cubic ordered alloy AuZn as a function of temperature. Measurements were made on single-crystal and polycrystalline samples using Resonant Ultrasound Spectroscopy (RUS), semi-adiabatic calorimetry and stress-strain measurements. Our results confirm that this alloy exhibits the shape-memory effect and a phase transition at 64.75 K that appears to be continuous (second-order) from the specific heat data. It is argued that the combination of equiatomic composition and a low transformation temperature constrain the chemical potential and its derivatives to exhibit behavior that lies at the borderline between that of a first-order (discontinuous) and a continuous phase transition. The acoustic dissipation does not peak at the transtion temperature as expected, but shows a maximum well into the low-temperature phase. The Debye temeprature value of 219 K, obtained from the low-temperature specific heat data is in favorable agreement with that determined from the acoustic data (207 K) above the transition.Comment: 25 pages, 6 figures, submitted to Phys. Rev.

Australia: PISA Australia—Excellence and Equity?

Australia’s education system reflects its history of federalism. State and territory governments are responsible for administering education within their jurisdiction and across the sector comprising government (public), Catholic systemic and other independent schooling systems. They collaborate on education policy with the federal government. Over the past two decades the federal government has taken a greater role in funding across the education sector, and as a result of this involvement and the priorities of federal governments of the day, Australia now has one of the highest rates of non-government schooling in the OECD. Funding equity across the sectors has become a prominent issue. Concerns have been compounded by evidence of declining student performance since Australia’s initial participation in PISA in 2000, and the increasing gap between our high achievers and low achievers. This chapter explores Australia’s PISA 2018 results and what they reveal about the impact of socioeconomic level on student achievement. It also considers the role of school funding and the need to direct support to those schools that are attempting to educate the greater proportion of an increasingly diverse student population including students facing multiple layers of disadvantage

Aharonov-Bohm-like effect for light propagating in nematics with disclinations

Using a geometric approach for the propagation of light in anisotropic media, we investigate what effect the director field of disclinations may have on the polarization state of light. Parallel transport around the defect, of the spinor describing the polarization, indicates the acquisition of a topological phase, in analogy with the Aharonov-Bohm effect.Comment: 6 pages, to appear in Europhysics Letter

A Search for OH Megamasers at z > 0.1. I. Preliminary Results

We present the preliminary results of a survey for OH megamasers underway at the Arecibo Observatory. The goals of the survey are to calibrate the luminosity function of OH megamasers to the low-redshift galaxy merger rate (0.1 < z < 0.2), and to use the enhanced sample of OH megamasers provided by the survey to study OH megamaser environments, engines, lifetimes, and structure. The survey should double the known OH megamaser sample to roughly 100 objects. Survey results will be presented in installments to facilitate community access to the data. Here we report the discovery of 11 OH megamasers and one OH absorber, and include upper limits on the isotropic 1667 MHz OH line luminosity of 53 other luminous infrared galaxies at z > 0.1. The new megamasers show a wide range of spectral properties, but are consistent with the extant set of 55 previously reported objects, only 8 of which have z > 0.1.Comment: 18 pages, 3 figures, accepted for publication in the Astronomical Journa

Does prior healthcare experience predict success on clinical courses and add value to admissions processes?

AbstractObjectivesThis work sought to assess whether prior clinical experience provided any guide to likely course achievement from three completed cohorts of Physician Associates at the University of Sheffield.MethodsSixty students who entered the PA course at TUoS since it began in 2016 were included in the study. Each students’ original course application was reviewed for healthcare experience and mapped against first sit examination scores. Statistical analysis was undertaken with a two-tailed t-test.ResultsNo correlation was found between previous healthcare experience and performance in examinations. Students with previous healthcare experience performed slightly worse than those without in the OSCE examination but not at a level of statistical significance.ConclusionsThe use of clinical experience as part of the criteria of entry does not predict success on a Physician Associate course. We support the position of the 2010 Ottawa conference that quality assured methodologies along with objective cut offs for previous academic attainment are the most appropriate way to select students for clinical courses.</jats:sec