Information Gains from Cosmic Microwave Background Experiments

To shed light on the fundamental problems posed by Dark Energy and Dark Matter, a large number of experiments have been performed and combined to constrain cosmological models. We propose a novel way of quantifying the information gained by updates on the parameter constraints from a series of experiments which can either complement earlier measurements or replace them. For this purpose, we use the Kullback-Leibler divergence or relative entropy from information theory to measure differences in the posterior distributions in model parameter space from a pair of experiments. We apply this formalism to a historical series of Cosmic Microwave Background experiments ranging from Boomerang to WMAP, SPT, and Planck. Considering different combinations of these experiments, we thus estimate the information gain in units of bits and distinguish contributions from the reduction of statistical errors and the `surprise' corresponding to a significant shift of the parameters' central values. For this experiment series, we find individual relative entropy gains ranging from about 1 to 30 bits. In some cases, e.g. when comparing WMAP and Planck results, we find that the gains are dominated by the surprise rather than by improvements in statistical precision. We discuss how this technique provides a useful tool for both quantifying the constraining power of data from cosmological probes and detecting the tensions between experiments.Comment: Published version. 14 pages, 4 figures, 1 tabl

Simulating the Large-Scale Structure of HI Intensity Maps

Intensity mapping of neutral hydrogen (HI) is a promising observational probe of cosmology and large-scale structure. We present wide field simulations of HI intensity maps based on N-body simulations of a $2.6\, {\rm Gpc / h}$ box with $2048^3$ particles (particle mass $1.6 \times 10^{11}\, {\rm M_\odot / h}$). Using a conditional mass function to populate the simulated dark matter density field with halos below the mass resolution of the simulation ($10^{8}\, {\rm M_\odot / h} < M_{\rm halo} < 10^{13}\, {\rm M_\odot / h}$), we assign HI to those halos according to a phenomenological halo to HI mass relation. The simulations span a redshift range of 0.35 < z < 0.9 in redshift bins of width $\Delta z \approx 0.05$ and cover a quarter of the sky at an angular resolution of about 7'. We use the simulated intensity maps to study the impact of non-linear effects and redshift space distortions on the angular clustering of HI. Focusing on the autocorrelations of the maps, we apply and compare several estimators for the angular power spectrum and its covariance. We verify that these estimators agree with analytic predictions on large scales and study the validity of approximations based on Gaussian random fields, particularly in the context of the covariance. We discuss how our results and the simulated maps can be useful for planning and interpreting future HI intensity mapping surveys.Comment: 35 pages, 19 Figures. Accepted for publication in JCA

An Integrated System at the Bleien Observatory for Mapping the Galaxy

We describe the design and performance of the hardware system at the Bleien Observatory. The system is designed to deliver a map of the Galaxy for studying the foreground contamination of low-redshift (z=0.13--0.43) H$_{\rm I}$ intensity mapping experiments as well as other astronomical Galactic studies. This hardware system is composed of a 7m parabolic dish, a dual-polarization corrugated horn feed, a pseudo correlation receiver, a Fast Fourier Transform spectrometer, and an integrated control system that controls and monitors the progress of the data collection. The main innovative designs in the hardware are (1) the pseudo correlation receiver and the cold reference source within (2) the high dynamic range, high frequency resolution spectrometer and (3) the phase-switch implementation of the system. This is the first time these technologies are used together for a L-band radio telescope to achieve an electronically stable system, which is an essential first step for wide-field cosmological measurements. This work demonstrates the prospects and challenges for future H$_{\rm I}$ intensity mapping experiments.Comment: 11 pages, 12 figures, 1 table, Submitted to MNRA

Accelerated Modeling of Near and Far-Field Diffraction for Coronagraphic Optical Systems

Accurately predicting the performance of coronagraphs and tolerancing optical surfaces for high-contrast imaging requires a detailed accounting of diffraction effects. Unlike simple Fraunhofer diffraction modeling, near and far-field diffraction effects, such as the Talbot effect, are captured by plane-to-plane propagation using Fresnel and angular spectrum propagation. This approach requires a sequence of computationally intensive Fourier transforms and quadratic phase functions, which limit the design and aberration sensitivity parameter space which can be explored at high-fidelity in the course of coronagraph design. This study presents the results of optimizing the multi-surface propagation module of the open source Physical Optics Propagation in PYthon (POPPY) package. This optimization was performed by implementing and benchmarking Fourier transforms and array operations on graphics processing units, as well as optimizing multithreaded numerical calculations using the NumExpr python library where appropriate, to speed the end-to-end simulation of observatory and coronagraph optical systems. Using realistic systems, this study demonstrates a greater than five-fold decrease in wall-clock runtime over POPPY's previous implementation and describes opportunities for further improvements in diffraction modeling performance.Comment: Presented at SPIE ASTI 2018, Austin Texas. 11 pages, 6 figure

Investigation of metal flow in bridge die extrusion of Alloy 6063 and subsequent effect on surface quality and weld seam integrity

This paper describes a detailed study of tube extrusion by simulation using finite element method (FEM). The finite element model used one-sixth of symmetry. The extrusion load, emperature evolution and metal flow were predicted. Innovative methods, combining both grid and surface tools, were used to define in detail the flow of material. These showed clearly the inner and outer surface formation mechanisms of the tube extrusion. The seam weld, an important quality indicator, was also evaluated by selecting an appropriate criterion

Vor den Toren von Vindonissa. Wohnen und Arbeiten in einem Handwerkerquartier in den canabae des Legionslagers (Windisch Zivilsiedlung West 2006 – 2008)

Erstmals erlaubt die Teilauswertung einer grossflächigen Ausgrabung einen vertieften Einblick in Entwicklung und Struktur der canabae legionis von Vindonissa. Im Westen des Lagers wurde um 30/40 n. Chr. ein römisches Gräberfeld aufgehoben, das Gelände wird neu parzelliert und zügig überbaut. Ein Grossbrand um 70 n. Chr zerstört das gesamte Quartier. Die Gebäude werden kurz nach 106 n. Chr. verlassen – annähernd gleichzeitig mit der Ankunft der XI. Legion in ihrem neuen Lager in Durostorum. Die Bewohner sind Handwerker – etwa Schmiede und Gerber. Sie dürften vorwiegend für das Lager produziert haben. Die von Legionsstandorten sonst bekannte Siedlungsdualität mit canabae legionis und vicus scheint für Vindonissa nicht zu existieren – die Zivilsiedlung ist insgesamt als canabae anzusprechen

Safer nightlife labels and charters: good practice standards.

Licences’ laws exist and have increased the quality of events and clubs during the last decade in most European countries. However, even for countries with a comprehensive licence law, a label is a complementary and sustainable solution adapted to the local realities. Because these labels and charters are developing participative and integrated approaches with all the nightlife stakeholders, promoting community empowerment and setting up actions for a responsible party’s culture, Labels and charters give a framework: >>To improve nightlife settings “in a healthiest way”; >>To raise awareness of partygoers on risk behaviours and how to reduce risks; >>To promote a positive and responsible party culture; >>To work together with nightlife scenes, partygoers, health NGO’s and administrations in a way of cooperation; >>To empower the nightlife community; >>To strengthen mediation and reduce public nuisance and violence around clubs. What are quality Labels and Charters? Safer nightlife Labels and Charters are global health promotion tools ensuring a high quality standard within the nightlife scene: A safer nightlife Label is developed to reward a club complying with official standards of quality and to indicate to consumers the quality of the service provided. A Label is a formal engagement to ensure the permanent availability of services in venues with strict criteria. A safer nightlife Charter is an official document signed by clubs, party organizers, cities and NGOs recognizing common objectives and specifying commitments to im¬prove health and security in clubs and parties. A Charter is an approach defining more orientations instead of criteria. It may be imperfectly applied due to reasons beyond the signatory’s control

CosmoSIS: Modular cosmological parameter estimation

Cosmological parameter estimation is entering a new era. Large collaborations need to coordinate high-stakes analyses using multiple methods; furthermore such analyses have grown in complexity due to sophisticated models of cosmology and systematic uncertainties. In this paper we argue that modularity is the key to addressing these challenges: calculations should be broken up into interchangeable modular units with inputs and outputs clearly defined. We present a new framework for cosmological parameter estimation, CosmoSIS, designed to connect together, share, and advance development of inference tools across the community. We describe the modules already available in CosmoSIS, including CAMB, Planck, cosmic shear calculations, and a suite of samplers. We illustrate it using demonstration code that you can run out-of-the-box with the installer available at http://bitbucket.org/joezuntz/cosmosisComment: Finally got around to updating to refereed version. 31 pages, 8 figure

„stercus ex latrinis" - Die unappetitliche Nachnutzung von Schacht MR6/MR 32 in der Region 17C der Unterstadt von Augusta Raurica

Im vorliegenden Aufsatz werden die Ergebnisse der interdisziplinären Auswertung der Verfüllung von Schacht MR 6/MR 32 vorgestellt, der anlässlich der Lehrgrabung «Kaiseraugst-Auf der Wacht» (2011–2013. 001) in der westlichen Unterstadt von Augusta Raurica (Region 17C) entdeckt wurde. Der rund 4,2 m tiefe, trocken gemauerte Schacht MR 6/MR 32, dessen primäre Verwendung (cella promptuaria? fossa nivalis?) nicht hinreichend geklärt ist, wurde wahrscheinlich in flavischer Zeit errichtet und bereits zu Beginn des 2. Jahrhunderts wieder aufgegeben und verfüllt (vgl. Schneider/Schwarz 2017 [in diesem Band]). Die archäologischen und mikromorphologischen Analysen haben gezeigt, dass es sich bei den unteren Füllschichten (Schichtpaket A) unter anderem um stercus, also um Fäkalien handelt, die wahrscheinlich in kurzem zeitlichem Abstand nacheinander eingebracht worden sind. Die Latrinensedimente sind nicht in situ entstanden, sondern stam-men aus ausgeschöpften Latrinengruben, die sich vermutlich in der näheren Umgebung von Schacht MR 6/MR 32 befanden. Zu einem geringeren Teil fanden sich in Schichtpaket A auch gewöhnliche Haus-haltabfälle, wobei ungeklärt bleibt, ob sich darin separate Entsorgungsvorgänge widerspiegeln oder ob diese zusammen mit den Latrinensedimenten in den Schacht gelangt sind. Das Fundmaterial aus den unteren Füllschichten (Ensemble A) datiert nach Aussage der Keramik, der Kleinfunde sowie der Fundmünzen in die Zeit zwischen 70/80 und 120/140 n. Chr. Ensemble A um-fasst folglich Fundmaterial, das während der ersten (ältesten) zivilen Siedlungsphase der Unterstadt von Augusta Raurica in der Region 17C in den Boden gekommen ist. Wichtigstes Ergebnis ist die Feststellung, dass sich die von der älteren Forschung vertretene Unterscheidung in eine «reiche» Oberstadtund eine «arme» Unterstadt im archäo(bio)logischen Fundmaterial aus Schacht MR 6/MR 32 nicht widerspiegelt. Im Gegenteil: Die Analyse des keramischen Fundmaterials, der Klein- und Grosstierknochen sowie der botanischen Makroreste hat gezeigt, dass die in der Umgebung von Schacht MR 6/MR 32 lebende Bevölkerung weitgehend romanisiert war und sich auch relativ vielseitig ernährt hat. Für eine gehobene Ernährung sprechen unter anderem die hohen Anteile von Schwein und Huhn bzw. von Jungtieren sowie die nachgewiesenen Fischarten und die botanischen Makroreste. Unter letztgenannten fanden sich zahlreiche in Augusta Raurica auch sonst belegte Gemüse-, Obst- und Gewürzarten. Besonders hervorzuheben sind im vorliegenden Fall die eher seltenen Nachweise von Gurke, Gartenkresse und Schwarzkümmel. Dass zwei «klassische Luxusindikatoren» – Austern und Mittelmeermakrelen – in Ensemble A fehlen, ist zwar erstaunlich, spricht aber nicht gegen eine Interpretation der Latrinensedimente als Relikte einer sozial gut gestellten Bevölkerung. Konkrete und weiterführende Hinweise zum Gesundheitszustand der in der Region 17C lebenden Bevölkerung lieferte eine aus Schichtpaket A entnommene Sedimentprobe. Darin fanden sich zahlreiche Eier sowohl des Peitschen- als auch des Spulwurms; diese Würmer verursachen unter anderem chronische Durchfallerkrankungen, die in der römischen Epoche weit verbreitet waren, und zwar – wie das vorliegende Beispiel zeigt – offensichtlich auch bei sozial besser gestellten Bevölkerungsschichten

The anatomy of neuroepithelial tumours

Many neurological conditions conceal specific anatomical patterns. Their study contributes to the understanding of disease biology and to tailored diagnostics and therapy. Neuroepithelial tumours exhibit distinct anatomical phenotypes and spatiotemporal dynamics that differ from those of other brain tumours. Brain metastases display a preference for the cortico-subcortical boundaries of watershed areas and have a predominantly spherical growth. Primary CNS lymphomas localize to the white matter and generally invade along fibre tracts. In neuroepithelial tumours, topographic probability mapping and unsupervised topological clustering have identified an inherent radial anatomy and adherence to ventriculopial configurations of specific hierarchical orders. Spatiotemporal probability and multivariate survival analyses have identified a temporal and prognostic sequence underlying the anatomical phenotypes of neuroepithelial tumours. Gradual neuroepithelial de-differentiation and declining prognosis follow (i) an expansion into higher order radial units; (ii) a subventricular spread; and (iii) the presence of mesenchymal patterns (expansion along white matter tracts, leptomeningeal or perivascular invasion, CSF spread). While different pathophysiological hypotheses have been proposed, the cellular and molecular mechanisms dictating this anatomical behaviour remain largely unknown. Here we adopt an ontogenetic approach towards the understanding of neuroepithelial tumour anatomy. Contemporary perception of histo- and morphogenetic processes during neurodevelopment permit us to conceptualize the architecture of the brain into hierarchically organized radial units. The anatomical phenotypes in neuroepithelial tumours and their temporal and prognostic sequences share remarkable similarities with the ontogenetic organization of the brain and the anatomical specifications that occur during neurodevelopment. This macroscopic coherence is reinforced by cellular and molecular observations that the initiation of various neuroepithelial tumours, their intratumoural hierarchy and tumour progression are associated with the aberrant reactivation of surprisingly normal ontogenetic programs. Generalizable topological phenotypes could provide the basis for an anatomical refinement of the current classification of neuroepithelial tumours. In addition, we have proposed a staging system for adult-type diffuse gliomas that is based on the prognostically critical steps along the sequence of anatomical tumour progression. Considering the parallels in anatomical behaviour between different neuroepithelial tumours, analogous staging systems may be implemented for other neuroepithelial tumour types and subtypes. Both the anatomical stage of a neuroepithelial tumour and the spatial configuration of its hosting radial unit harbour the potential to stratify treatment decisions at diagnosis and during follow-up. More data on specific neuroepithelial tumour types and subtypes are needed to increase the anatomical granularity in their classification and to determine the clinical impact of stage-adapted and anatomically tailored therapy and surveillance