How the minuscule can contribute to the big picture: the neutron electric dipole moment project at TRIUMF

A permanent electric dipole moment (EDM) of a fundamental particle violates both parity (P) and time (T) reversal symmetry and combined charge and parity (CP) reversal symmetry if the combined reversal of charge, parity \textit{and} time (CPT) is preserved. It is a very promising place to search for physics beyond the Standard Model. Ultracold neutrons (UCN) are the ideal tool to study the neutron electric dipole moment since they can be observed for hundreds of seconds. This article summarizes the current searches for the neutron EDM using UCN and introduces the project to measure the neutron electric dipole moment at TRIUMF using its unique accelerator driven spallation neutron and liquid helium UCN source. The aim is to reach a sensitivity for the neutron EDM of around $10^{-27} \,e \cdot$cm.Comment: 12 pages, 6 figures, MENU 2016 Conference, Kyoto, Japa

Prognostic variables and scores identifying the last year of life in COPD: a systematic review protocol

Introduction People living with advanced chronic obstructive pulmonary disease (COPD) suffer from significant morbidity, reduced quality of life and high mortality, and are likely to benefit from many aspects of a palliative care approach. Prognostic estimates are a meaningful part of decision-making and better evidence for such estimates would facilitate advance care planning. We aim to provide quality evidence on known prognostic variables and scores which predict a prognosis in COPD of <12 months for use in the community. Methods and analysis We will conduct a systematic review of randomised or quasi-randomised controlled trials, prospective and retrospective longitudinal cohort and case–control studies on prognostic variables, multivariate scores or models for COPD. The search will cover the period up to April 2016. Study selection will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, with data extraction using fields from the Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies (CHARMS) checklist for multivariate models, and study quality will be assessed using a modified version of the Quality In Prognosis Studies (QUIPS) tool. Ethics and dissemination The results will be disseminated through peer-reviewed publications and national and international conference presentations

GRB990123: The Case for Saturated Comptonization

The recent simultaneous detection of optical, X-ray and gamma-ray photons from GRB990123 during the burst provides the first broadband multi-wavelength characterization of the burst spectrum and evolution. Here we show that a direct correlation exists between the time-varying gamma-ray spectral shape and the prompt optical emission. This combined with the unique signatures of the time-resolved spectra of GRB990123 convincingly supports earlier predictions of the saturated Comptonization model. Contrary to other suggestions, we find that the entire continuum from optical to gamma-rays can be generated from a single source of leptons (electrons and pairs). The optical flux only appears to lag the gamma-ray flux due to the high initial Thomson depth of the plasma. Once the plasma has completely thinned out, the late time afterglow behavior of our model is the same as in standard models based on the Blandford-McKee (1976) solution.Comment: 10 pages, including 3 figures and 1 table, submitted to The Astrophysical Journal Letter

NGC1333/IRAS4: A multiple star formation laboratory

We present SCUBA observations of the protomultiple system NGC1333/IRAS4 at 450um and 850um. The 850um map shows significant extended emission which is most probably a remnant of the initial cloud core. At 450um, the component 4A is seen to have an elongated shape suggestive of a disk. Also we confirm that in addition to the 4A and 4B system, there exists another component 4C, which appears to lie out of the plane of the system and of the extended emission. Deconvolution of the beam reveals a binary companion to IRAS4B. Simple considerations of binary dynamics suggest that this triple 4A-4BI-4BII system is unstable and will probably not survive in its current form. Thus IRAS4 provides evidence that systems can evolve from higher to lower multiplicity as they move towards the main sequence. We construct a map of spectral index from the two wavelengths, and comment on the implications of this for dust evolution and temperature differences across the map. There is evidence that in the region of component 4A the dust has evolved, probably by coagulating into larger or more complex grains. Furthermore, there is evidence from the spectral index maps that dust from this object is being entrained in its associated outflow.Comment: 10 pages, 10 figures. To appear in MNRAS. Uses mn.sty. Also available at http://www.astro.phys.ethz.ch/papers/smith/smith_p_m.htm

A Possible Formation Scenario for Dwarf Spheroidal Galaxies - II: A Parameter Study

Dwarf spheroidal (dSph) galaxies are considered the basic building blocks of the galaxy formation process in the LCDM (Lambda Cold Dark Matter) hierarchical cosmological model. These galaxies are believed to be the most dark matter (DM) dominated systems known, have the lowest stellar content, and are poor in gas. Many theories attempt to explain the formation of dSph galaxies resorting to the fact that these galaxies are mainly found orbiting large galaxies or invoking other mechanisms of interactions. Here we show the full set of simulation as an extension of our fiducial model, where we study the formation of classical dSph galaxies in isolation by dissolving star clusters within the DM halo of the dwarf galaxy. In our parameter survey we adopt cored and cusped DM halo profiles and consider different numbers of dissolving star clusters. We investigate the dependency of observable quantities with different masses and scale-lengths of the DM halo and different star formation efficiencies (SFE). We find that our proposed scenario explains many features of the classical dSph galaxies of the Milky Way, like their morphology and their dynamics. We see trends how the surface brightness and the scale-length of the luminous component vary with the parameters of our simulations. We also identify how irregularities in their shape, i.e. clumpiness and ellipticity vary in our simulations. In velocity space, we identify the parameters leading to flat velocity dispersions curves. We recognize kinematically cold substructures in velocity space, named fossil remnants and stemming from our unique initial conditions, which alter the expected results. These streaming motions are considered as a key feature for future observation with high resolution to validate our scenario.Comment: 23 pages, 9 figures, 4 Tables, accepted for publication in MNRA