76 resultados para The near-poor

em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast


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We present the results of the one-year long observational campaign of the type 11 plateau SN 2005cs, which exploded in the nearby spiral galaxy M51 (the Whirlpool galaxy). This extensive data set makes SN 2005cs the best observed low-luminosity, Ni-56-poor type II plateau event so far and one of the best core-collapse supernovae ever. The optical and near-infrared spectra show narrow P-Cygni lines characteristic of this SN family, which are indicative of a very low expansion velocity (about 1000 km s(-1)) of the ejected material. The optical light curves cover both the plateau phase and the late-time radioactive tail, until about 380 d after core-collapse. Numerous unfiltered observations obtained by amateur astronomers give us the rare opportunity to monitor the fast rise to maximum light, lasting about 2 cl. In addition to optical observations, we also present near-infrared light curves that (together with already published ultraviolet observations) allow us to construct for the first time a reliable bolometric light Curve for an object of this class. Finally. comparing the observed data withthose derived front it semi-analytic model, we infer for SN 2005cs a Ni-56 mass of about 3 x 10(-3) M-circle dot a total ejected mass of 8-13 M-circle dot and an explosion energy of about 3 x 10(50) erg.

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Arguments are given that lead to a formalism for calculating near K-edge structure in electron energy loss spectroscopy (EELS). This is essentially a one electron picture, while many body effects may be introduced at different levels, such as the local density approximation to density functional theory or the GW approximation to the electron self-energy. Calculations are made within the all electron LMTO scheme in crystals with complex atomic and electronic structures, and these are compared with experiment. (c) 2004 Elsevier B.V. All rights reserved.

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We investigate the ability of the local density approximation (LDA) in density functional theory to predict the near-edge structure in electron energy-loss spectroscopy in the dipole approximation. We include screening of the core hole within the LDA using Slater's transition state theory. We find that anion K-edge threshold energies are systematically overestimated by 4.22 +/- 0.44 eV in twelve transition metal carbides and nitrides in the rock-salt (B1) structure. When we apply this 'universal' many-electron correction to energy-loss spectra calculated within the transition state approximation to LDA, we find quantitative agreement with experiment to within one or two eV for TiC, TiN and VN. We compare our calculations to a simpler approach using a projected Mulliken density which honours the dipole selection rule, in place of the dipole matrix element itself. We find remarkably close agreement between these two approaches. Finally, we show an anomaly in the near-edge structure in CrN to be due to magnetic structure. In particular, we find that the N K edge in fact probes the magnetic moments and alignments of ther sublattice.

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A recent improved version of the semiclassical-quantal approach has been applied to the e(-)-H near-threshold ionization for theta (12) = 180 degrees geometry. It is found, that unlike other sophisticated theoretical methods such as distorted wave theory or convergent close-coupling calculation, the present relatively simpler approach produces correct behavior and numerical values for the triple-differential cross sections. We compare our results with recent absolute measurements and accurate numerical calculations at 2 eV and 4 eV above the threshold at constant theta (12) geometry.

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A new type of near-infrared emitting rare-earth complex has been synthesised, consisting of three bis(perfluoroalkylsulfonyl)imide ligands and one 1,10-phenanthroline molecule. The chelate rings formed by the rare-earth ion and the bidentate ligands do not contain any carbon atoms and can hence be considered as 'inorganic' chelate rings. The absence of C-H stretching vibration modes in the first coordination sphere of the rare-earth ion and the presence of a light-harvesting moiety (1,10-phenanthroline) bound to the rare-earth ion result in a complex that can be efficiently excited and exhibits intense near-infrared luminescence. (C) 2004 Elsevier B.V. All rights reserved.

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This examines the workings of the Irish Poor Law in the town of Ballymoney, Co. Antrim, during the period between the end of the Great Famine and Partition. It focuses both on those who administered and those who used the poor law and argues that for the former it provided an important route into local politics and for the latter it represented a crucial strand in the limited strategies for survival open to them. It also demonstrates the impact that local political outlook had on both the administration and the experience of poor relief.

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We present nine near-infrared (NIR) spectra of supernova (SN) 2005cf at epochs from -10 to +42d with respect to B-band maximum, complementing the existing excellent data sets available for this prototypical Type Ia SN at other wavelengths. The spectra show a time evolution and spectral features characteristic of normal Type Ia SNe, as illustrated by a comparison with SNe 1999ee, 2002bo and 2003du. The broad-band spectral energy distribution (SED) of SN 2005cf is studied in combined ultraviolet (UV), optical and NIR spectra at five epochs between ~8d before and ~10d after maximum light. We also present synthetic spectra of the hydrodynamic explosion model W7, which reproduce the key properties of SN 2005cf not only at UV-optical as previously reported, but also at NIR wavelengths. From the radiative-transfer calculations we infer that fluorescence is the driving mechanism that shapes the SED of SNe Ia. In particular, the NIR part of the spectrum is almost devoid of absorption features, and instead dominated by fluorescent emission of both iron-group material and intermediate-mass elements at pre-maximum epochs, and pure iron-group material after maximum light. A single P-Cygni feature of Mgii at early epochs and a series of relatively unblended Coii lines at late phases allow us to constrain the regions of the ejecta in which the respective elements are abundant. © 2012 The Authors Monthly Notices of the Royal Astronomical Society © 2012 RAS.

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We present here a detailed study of the complex relationship between the electromagnetic near-field and far-field responses of "real" nanostructured metallic surfaces. The near-field and far-field responses are specified in terms of (spectra of) the surface-enhanced Raman-scattering enhancement factor (SERS EF) and optical extinction, respectively. First, it is shown that gold nanorod- and nanotube-array substrates exhibit three distinct localized surface plasmon resonances (LSPRs): a longitudinal, a transverse, and a cavity mode. The cavity mode simultaneously has the largest impact on the near-field behavior (as observed through the SERS EF) and the weakest optical interaction: It has a "near-field-type" character. The transverse and longitudinal modes have a significant impact on the far-field behavior but very little impact on SERS: They have a "far-field-type" character. We confirm the presence of the cavity mode using a combination of SERS EF spectra, electron microscopy, and electromagnetic modeling and thus clearly illustrate and explain the (lack of) correlation between the SERS EF spectra and the optical response in terms of the contrasting character of the three LSPRs. In doing so, we experimentally demonstrate that, for a surface that supports multiple LSPRs, the near-field and far-field properties can in fact be tuned almost independently. It is further demonstrated that small changes in geometrical parameters that tune the spectral location of the LPSRs can also drastically influence the character of these modes, resulting in certain unusual behavior, such as the far-field resonance redshift as the near-field resonance blueshifts. DOI: 10.1103/PhysRevX.3.011001

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This book explores welfare provision in Ireland from the revolutionary period to the 1940s, This work is a significant addition to the growing historiography of twentieth-century Ireland which moves beyond political history. It demonstrates that concepts of respectability, deservingness, and social class where central dynamics in Irish society and welfare practices. This book provides the first major study of local welfare practices, policies, and attitudes towards poverty and the poor in this era.

This book’s exploration of the poor law during revolutionary and independent Ireland provides fresh and original insights into this critical juncture in Irish history. It charts the transformation of the former workhouse system into a network of local authority welfare and healthcare institutions including county homes, county and hospital hospitals, and mother and baby homes. This book provides historical context to current day debates and controversies relating to the institutionalisation of unwed mothers and child welfare policies.

This book undertakes two cases studies on county Kerry and Cork city; also, Irish experiences are placed against the backdrop of wider transnational trends.

This work has multiple audiences and will appeal to those interested in Irish social, culture, economic and political history. This book will also appeal to historians of welfare, the poor law, and the social history of medicine. It also informs modern-day social affairs.