DISSPLA plotting routines for the G-189A EC/LS computer program

Data from a G-189A execution is formatted and plotted. The plotting may be done at the time of execution of the program. DISSPLA plot packages are used. The user has the choice of FR80 or TEKTRONIX output

Cooper pair correlations and energetic knock-out reactions

Two-nucleon removal (or knock-out) reactions at intermediate energies are a developing tool for both nuclear spectroscopy and for the study of certain nucleon correlations in very exotic and some stable nuclei. We present an overview of these reactions with specific emphasis on the nature of the two-nucleon correlations that can be probed. We outline future possibilities and tests needed to fully establish these sensitivities.Comment: 12 pages, 3 figures: Contribution to the Volume 50 years of Nuclear BCS edited by World Scientifi

Catching the head, tail, and everything in between: a streaming algorithm for the degree distribution

The degree distribution is one of the most fundamental graph properties of interest for real-world graphs. It has been widely observed in numerous domains that graphs typically have a tailed or scale-free degree distribution. While the average degree is usually quite small, the variance is quite high and there are vertices with degrees at all scales. We focus on the problem of approximating the degree distribution of a large streaming graph, with small storage. We design an algorithm headtail, whose main novelty is a new estimator of infrequent degrees using truncated geometric random variables. We give a mathematical analysis of headtail and show that it has excellent behavior in practice. We can process streams will millions of edges with storage less than 1% and get extremely accurate approximations for all scales in the degree distribution. We also introduce a new notion of Relative Hausdorff distance between tailed histograms. Existing notions of distances between distributions are not suitable, since they ignore infrequent degrees in the tail. The Relative Hausdorff distance measures deviations at all scales, and is a more suitable distance for comparing degree distributions. By tracking this new measure, we are able to give strong empirical evidence of the convergence of headtail

Near-infrared and X-ray obscuration to the nucleus of the Seyfert 2 galaxy NGC 3281

We present the results of a near-infrared and X-ray study of the Seyfert 2 galaxy NGC 3281. Emission from the Seyfert nucleus is detected in both regions of the electromagnetic spectrum, allowing us to infer both the equivalent line of sight hydrogen column density, N_H = 71.0(+11.3,-12.3)e26/m^2 and the extinction due to dust, A_V = 22+/-11 magnitudes (90% confidence intervals). We infer a ratio of N_H/A_V which is an order of magnitude larger than that determined along lines of sight in the Milky Way and discuss possible interpretations. We consider the most plausible explanation to be a dense cloud in the foreground of both the X-ray and infrared emitting regions which obscures the entire X-ray source but only a fraction of the much larger infrared source.Comment: 23 pages including 9 figure

Luminescence Dating of Sediments from Ancient Irrigation Features, and Associated with Occupation of the Hinterland around Anuradhapura, Sri Lanka

This study supports a new investigation into the development and decline of irrigation and associated human activity in the Anuradhapura Hinterland, Sri Lanka (section 2). Optically stimulated luminescence (OSL) age determinations have been made for a variety of sediments from bund and tank systems, irrigation channels, palaeosols and ceramic scatter horizons in the Anuradhapura hinterland (section 3). The geomorphological and archaeological significance of the age determinations has been reviewed in the light of the luminescence results and the samples’ depositional contexts, to constrain the deposition/formation dates of the sampled sediments integrate the OSL results with independent archaeological and historical expectations (section 6). A total of 26 age determinations were made (section 5.3). Dose rate determinations were made using thick source beta counting, high-resolution gamma spectrometry, field gamma spectrometry, measured water contents and calculated cosmic dose rates (sections 4.2.1, 5.1). Equivalent dose determinations were made (sections 4.2.2, 5.2) using the OSL signals from sand sized grains of quartz separated from each sample. Dose rates ranged from 1.1 to 5.0 mGy/a, equivalent dose values ranged from 0.29 to 33 Gy. Age estimates for these samples ranged from 0.14 to 13 ka, the average being 2.9 ka ± 3.1 (section 5.3). Uncertainties on the age estimates were commonly 7% at one standard error. The OSL age estimates from the largest bund and some ceramic scatter sites were greater than 2000 BC. This is older than expected on archaeological grounds and further investigation of these sites may be warranted. The OSL results from the other samples in the present study date bund construction during the initial urbanisation of Anuradhapura c. 400BC, coincident with the major Nachchaduwa bund construction c. 300AD, and in the Late Iron Age / Early Mediaeval period c. 600AD. They date abandonment of one irrigation channel to the 8th Century AD and its infill up to the late 10th Century when Anuradhapura was finally sacked. A further 8 age estimates, from silts and colluvium, relate to the collapse of infrastructure in the Anuradhapura hinterland during the 10th century and continued landscape response during the 11th century, followed by the lead-in to restoration of the irrigation system during the colonial era

Luminescence investigations at Quendale (Broo Peninsula, Shetland)

This report is concerned with optically stimulated luminescence (OSL) investigations of sediment samples collected from ongoing University of Southern Maine archaeological excavations at the Links of Quendale, southern Shetland, investigating the early-modern township of Broo. 11 sediment samples were submitted to the luminescence laboratory at SUERC for OSL dating by Ian Simpson. This report summaries the protocols, and laboratory analysis, employed in quartz single aliquot regenerative (SAR) OSL dating, as used to construct an OSL chronology for wind-blown sands in proximity to the Broo excavations, in association with archaeological structures (5 samples), and for sands in the coastal and inland dune systems (6 samples). The chronology established for the inland sands, in contexts associated with the Broo 2 building and enclosure, spans from AD1540 ± 40 (SUTL2441) through to AD1810 ± 25 (SUTL2519), encompassing the archaeological period of interest. The dates obtained for sands within the enclosed and unenclosed areas to the immediate east and southwest of the excavated Broo site, are AD1760 ± 30 - AD1760 ± 25, and AD1810 ± 25 (SUTL2517-2518 and 2519, respectively), are consistent with the expectation that the clean sands which infill these structures, post-date the period in which the Broo township was abandoned. The coastal sand accumulations, as so far dated, yielded luminescence ages of 2380 ± 230 BC (SUTL2526), 1510 ± 270 BC (SUTL2527), AD 1030 ± 80 (SUTL2528), AD 1690 ± 50 (SUTL2529), AD 1720 ± 20 (SUTL2530) and a mixed-age sample with youngest component at AD 1955 ± 15 (SUTL2531), implying periods of sand mobilisation, synchronous with sand deposition in Orkney and northern Scotland, in the late Neolithic, the Early Bronze Age, the Norse period, the early-modern, and modern periods. This work suggests that the present-day physio-geographical setting of the Quendale Links, comprised of the coastal sand barrier, and the inland dune fields, is a product of a prolonged history of sand mobilisation, erosion and deposition from the Neolithic to the present day. Furthermore, the emerging temporal framework, coupled with the spatial distribution of dune forms across the Links, raises questions as to whether Little Ice Age storms were responsible for deposition, or erosive destruction of older dune-forms, and the re-mobilisation of this sediment. To test these ideas, profiling methods, both field- and laboratory- based, could be employed to obtain a more complete temporal and spatial characterisation of the dune systems and excavated sequences. Further OSL sampling and dating would be needed to define the vertical and lateral chronostratigraphies of the environmental features in the landscape and their relationships to archaeological structures

Technological learning: towards an integrated model

The acquisition and growth of technological knowledge is fundamental to competitive advantage in the emerging knowledge economy. This article explores the notion of technological learning as a means of developing the capabilities that underpin long term sustainable innovation. The research project was designed to identify new ways of understanding learning in the context of technology-driven SMEs, so the methods employed were essentially inductive in nature. This has resulted in the development of a comprehensive framework comprising four inter-related knowledge categories (Identity, Direction, Capability, and Relationship), each of which has an associated learning process (learning by reflecting, learning by strategising, learning by doing, and learning by interacting). We argue that it is the interaction between these knowledge categories that generates the new insights that are essential to technological learning