The Changing Fractions of Type Ia Supernova NUV-Optical Subclasses with Redshift

UV and optical photometry of Type Ia supernovae (SNe Ia) at low redshift have revealed the existence of two distinct color groups, NUV-red and NUV-blue events. The color curves differ primarily by an offset, with the NUV-blue u- color curves bluer than the NUV-red curves by 0.4 mag. For a sample of 23 low-z SNe~Ia observed with Swift, the NUV-red group dominates by a ratio of 2:1. We compare rest-frame UV/optical spectrophotometry of intermediate and high-z SNe Ia with UVOT photometry and HST spectrophotometry of low-z SNe Ia, finding that the same two color groups exist at higher-z, but with the NUV-blue events as the dominant group. Within each red/blue group, we do not detect any offset in color for different redshifts, providing insight into how SN~Ia UV emission evolves with redshift. Through spectral comparisons of SNe~Ia with similar peak widths and phase, we explore the wavelength range that produces the UV/OPT color differences. We show that the ejecta velocity of NUV-red SNe is larger than that of NUV-blue objects by roughly 12% on average. This velocity difference can explain some of the UV/optical color difference, but differences in the strengths of spectral features seen in meanspectra require additional explanation. Because of the different b-v colors for these groups, NUV-red SNe will have their extinction underestimated using common techniques. This, in turn, leads to under-estimation of the optical luminosity of the NUV-blue SNe~Ia, in particular, for the high-redshift cosmological sample. Not accounting for this effect should thus produce a distance bias that increases with redshift and could significantly bias measurements of cosmological parameters.Comment: submitted to Ap

Using Geovisual Analytics to investigate the performance of Geographically Weighted Discriminant Analysis

Geographically Weighted Discriminant Analysis (GWDA) is a method for prediction and analysis of categorical spatial data. It is an extension of Linear Discriminant Analysis (LDA) that allows the relationship between the predictor variables and the categories to vary spatially. This is also referred to spatial non-stationarity. If spatial non-stationarity exists, GWDA should model the relationship between the categories and predictor variables more accurately, thus resulting in a lower classification uncertainty and ultimately a higher classification accuracy. The GWDA output also requires interpretation to understand which variables are important in driving the classification in different geographical regions. This research uses interactive visualisations from the field of geovisual analytics to investigate the performance of GWDA in terms of classification accuracy, classification uncertainty and spatial non-stationarity. The methodology is demonstrated in a case study that uses GWDA to examine the relationship between county level voting patterns in the 2004 US presidential election and five socio-economic indicators. This research builds on existing techniques to interpret the GWDA output and provides additional insight into the processes driving the classification. It also demonstrates a practical application of geovisual analytic tools

Alien Registration- Foley, Peter (Portland, Cumberland County)

https://digitalmaine.com/alien_docs/23792/thumbnail.jp

Early and Late-Time Observations of SN 2008ha: Additional Constraints for the Progenitor and Explosion

We present a new maximum-light optical spectrum of the the extremely low luminosity and exceptionally low energy Type Ia supernova (SN Ia) 2008ha, obtained one week before the earliest published spectrum. Previous observations of SN 2008ha were unable to distinguish between a massive star and white dwarf origin for the SN. The new maximum-light spectrum, obtained one week before the earliest previously published spectrum, unambiguously shows features corresponding to intermediate mass elements, including silicon, sulfur, and carbon. Although strong silicon features are seen in some core-collapse SNe, sulfur features, which are a signature of carbon/oxygen burning, have always been observed to be weak in such events. It is therefore likely that SN 2008ha was the result of a thermonuclear explosion of a carbon-oxygen white dwarf. Carbon features at maximum light show that unburned material is present to significant depths in the SN ejecta, strengthening the case that SN 2008ha was a failed deflagration. We also present late-time imaging and spectroscopy that are consistent with this scenario.Comment: ApJL, accepted. 5 pages, 3 figure

Moving NRQCD for B Form Factors at High Recoil

We derive the continuum and lattice tree-level moving NRQCD (mNRQCD) through order 1/m^2. mNRQCD is a generalization of NRQCD for dealing with hadrons with nonzero velocity u_mu. The quark's total momentum is written as P^mu=Mu^mu+k^mu where k^mu << Mu^mu is discretized and Mu^mu is treated exactly. Radiative corrections to couplings on the lattice are discussed. mNRQCD is particularly useful for calculating B->pi and B->D form factors since errors are similar at low and high recoil.Comment: 3 pages, 1 figure, Lattice2002(heavyquark

The Paula principle: How and why women work below their level of competence

Book review of The Paula Principle: How and why Women Work Below Their Level of Competence by Tom Schuller.Annai, 42, from Melbourne, believes a lack of self-confidence stopped her from being promoted in the media and advertising worlds. "I used to watch this guy at work," she says. "He wasn't competent but he was the most extraordinary self-promoter I've ever seen. It made me realise how I needed to put myself forward more." This familiar story from the The Sydney Morning Herald in June 2017 appears in a discussion of why women, successfully educated and competent in every way, so frequently end up in a job that doesn’t reflect their ability. It’s one of the questions Tom Schuller asks in The Paula Principle: How and why Women Work Below Their Level of Competence2. The stories Schuller uncovers about women’s experience of the workplace is underpinned by a wealth of data from OECD countries in which it is clear that women have overtaken men educationally at every level and yet somehow this isn’t matched by success in employment. For example, Schuller reminds us that women have overtaken men, at school leaving certificate level at top of course in the High School Certificate in Australia at university entrance level at attendance in full-time further and higher education at highest level in university finals in medical school exams…Published versio

CLOSING THE TECHNOLOGY GAP: PARTNER FORCE DIGITAL TOOLS FOR INFORMATION ADVANTAGE, PROJECT I-SHARE–INFORMATION SHARING, AND HOSTING ADVANCED REMOTE ECOSYSTEM ASSESSMENTS

Includes Supplementary MaterialProject ISHARE validated the theory that partner force data-sharing platforms require early iteration with foreign partners to ensure suitable design and create long-term adoption. Strategic competition requires reassessing how U.S. SOF cultivates operational relationships and shares critical data and information between partners. The operational relationships developed by SOF teams must modernize through secure digital tools to merge physical and digital personas for persistent engagement and information sharing. The project assessed two emerging platforms with partners in the Philippines. Survey results indicate that both platforms could be effective for operational use but lack sustainable connectivity for remote areas. The results highlighted that 55% of partner force respondents use unsecured apps to share data with U.S. SOF. Additionally, 66% of respondents agreed that the Civil Knowledge Integration-Tactical Assault Kit (CKI-TAK) or Field Information Support Tool (FIST) would reduce their dependence on unsecured platforms. Survey results, including respondents from over 25 nations, confirmed that partner nations do not provide their forces with the necessary digital tools for COP development and secure data sharing. The in-country assessments inform recommendations to develop next-generation secure partner force data-sharing platforms at the edge for both Mil-Mil and Civ-Mil coordination and use such platforms as a deterrence mechanism in Taiwan.Outstanding ThesisMajor, United States ArmyMajor, United States ArmyApproved for public release. Distribution is unlimited

DCU collaborative video search system

This paper describes the Dublin City University collaborative video search system. The system is a development on our previous year's VideOlympics submission which will explore the notion of division of labour and sharing of knowledge across collaborating users engaged in a shared search. Division of labour and sharing of knowledge across collaborating searchers is realised through system-mediated coordination of the search