University of Portsmouth

About: University of Portsmouth is a education organization based out in Portsmouth, Portsmouth, United Kingdom. It is known for research contribution in the topics: Population & Galaxy. The organization has 5452 authors who have published 14256 publications receiving 424346 citations. The organization is also known as: Portsmouth and Gosport School of Science and Art & Portsmouth and Gosport School of Science and the Arts.

The Intermediate-Scale Clustering of Luminous Red Galaxies

Abstract: We report the intermediate-scale (0.3-40 h-1 Mpc) clustering of 35,000 luminous early-type galaxies at redshifts 0.16-0.44 from the Sloan Digital Sky Survey. We present the redshift space two-point correlation function ξ(s), the projected correlation function wp(rp), and the deprojected real space correlation function ξ(r), for approximately volume-limited samples. As expected, the galaxies are highly clustered, with the correlation length varying from 9.8 ± 0.2 to 11.2 ± 0.2 h-1 Mpc, dependent on the specific luminosity range. For the -23.2 < Mg < -21.2 sample, the inferred bias relative to that of L* galaxies is 1.84 ± 0.11 for 1 h-1 Mpc < rp 10 h-1 Mpc, with yet stronger clustering on smaller scales. We detect luminosity-dependent bias within the sample but see no evidence for redshift evolution between z = 0.2 and z = 0.4. We find a clear indication for deviations from a power-law in the real space correlation function, with a dip at ~2 h-1 Mpc scales and an upturn on smaller scales. The precision measurements of these clustering trends offer new avenues for the study of the formation and evolution of these massive galaxies.

Historical GIS: structuring, mapping and analysing geographies of the past

Abstract: The last 10 years have seen a sudden rise in interest in the use of Geographical Information Systems (GIS) in historical research. This has led to a field that has become known as `historical GIS'. This development started in the more quantitative ends of the discipline but has spread to encompass qualitative research as well. Interest in historical GIS is not restricted to researchers who would previously have regarded themselves as historical geographers, but has in fact led to an increased awareness of the importance of geography from across the discipline of history. This paper introduces historical GIS and critically evaluates how it is affecting the practice of historical geography.

When no means no

Abstract: Cultural discourses of femininity and women's social role have historically and traditionally been constructed around motherhood. However, recent studies into women's childbearing intentions have revealed an increasing number of women in Western Europe and the United States choosing to remain childless. Thus, a distinction has emerged between cultural discourses on femininity and the experiences of an increasing number of women. This article considers the questions that emerge from this. In particular, to what extent and in what ways might cultural discourses of motherhood and femininity have declined and transformed as women's lives have changed. What might be the implications of this for constructions of femininity and identity in women. Drawing on an empirical study into voluntary childlessness amongst women, this article argues that pronatalist discourses and those that denigrate voluntary childlessness persist despite the considerable changes and increased autonomy experienced by women during the second half of the 20th century. However, through rejecting and resisting discourses that conflate femininity with motherhood, childless women create new discourses that can subvert and transform constructions of femininity. The article concludes that the advent of these new and alternative discourses signify the emergence of a radical feminine identity, distinct and unshackled from motherhood.

The sdss-iii baryon oscillation spectroscopic survey: the quasar luminosity function from data release nine

Abstract: We present a new measurement of the optical quasar luminosity function (QLF), using data from the Sloan Digital Sky Survey-III: Baryon Oscillation Spectroscopic Survey (SDSS-III: BOSS). From the SDSS-III Data Release Nine, a uniform sample of 22,301 i {approx}< 21.8 quasars are selected over an area of 2236 deg{sup 2}, with confirmed spectroscopic redshifts between 2.2 < z < 3.5, filling in a key part of the luminosity-redshift plane for optical quasar studies. The completeness of the survey is derived through simulated quasar photometry, and this completeness estimate is checked using a sample of quasars selected by their photometric variability within the BOSS footprint. We investigate the level of systematics associated with our quasar sample using the simulations, in the process generating color-redshift relations and a new quasar K-correction. We probe the faint end of the QLF to M{sub i} (z = 2.2) Almost-Equal-To -24.5 and see a clear break in the QLF at all redshifts up to z = 3.5. A log-linear relation (in log {Phi}* - M*) for a luminosity evolution and density evolution model is found to adequately describe our data within the range 2.2 < z < 3.5; across this interval the break luminosity increases bymore » a factor of {approx}2.6 while {Phi}* declines by a factor of {approx}8. At z {approx}< 2.2 our data are reasonably well fit by a pure luminosity evolution model, and only a weak signature of ''AGN downsizing'' is seen, in line with recent studies of the hard X-ray luminosity function. We compare our measured QLF to a number of theoretical models and find that models making a variety of assumptions about quasar triggering and halo occupation can fit our data over a wide range of redshifts and luminosities.« less

Mathematical modeling and physical reality in noncovalent interactions

Abstract: The Hellmann-Feynman theorem provides a straightforward interpretation of noncovalent bonding in terms of Coulombic interactions, which encompass polarization (and accordingly include dispersion) Exchange, Pauli repulsion, orbitals, etc, are part of the mathematics of obtaining the system’s wave function and subsequently its electronic density They do not correspond to physical forces Charge transfer, in the context of noncovalent interactions, is equivalent to polarization The key point is that mathematical models must not be confused with physical reality