181 research outputs found

    Nova light curves from the Solar Mass Ejection Imager (SMEI) - II. The extended catalogue

    Get PDF
    We present the results from observing nine Galactic novae in eruption with the Solar Mass Ejection Imager (SMEI) between 2004 and 2009. While many of these novae reached peak magnitudes that were either at or approaching the detection limits of SMEI, we were still able to produce light curves that in many cases contained more data at and around the initial rise, peak, and decline than those found in other variable star catalogs. For each nova, we obtained a peak time, maximum magnitude, and for several an estimate of the decline time (t2). Interestingly, although of lower quality than those found in Hounsell et al. (2010a), two of the light curves may indicate the presence of a pre-maximum halt. In addition the high cadence of the SMEI instrument has allowed the detection of low amplitude variations in at least one of the nova light curves

    The expanding dusty bipolar nebula around the nova V1280 Sco

    Get PDF
    V1280 Sco is one of the slowest dust-forming nova ever historically observed. We performed multi-epoch high-spatial resolution observations of the circumstellar dusty environment of V1280 Sco to investigate the level of asymmetry of the ejecta We observed V1280 Sco in 2009, 2010 and 2011 using unprecedented high angular resolution techniques. We used the NACO/VLT adaptive optics system in the J, H and K bands, together with contemporaneous VISIR/VLT mid-IR imaging that resolved the dust envelope of V1280 Sco, and SINFONI/VLT observations secured in 2011. We report the discovery of a dusty hourglass-shaped bipolar nebula. The apparent size of the nebula increased from 0.30" x 0.17" in July 2009 to 0.64" x 0.42" in July 2011. The aspect ratio suggests that the source is seen at high inclination. The central source shines efficiently in the K band and represents more than 56+/-5% of the total flux in 2009, and 87+/-6% in 2011. A mean expansion rate of 0.39+/-0.03 mas per day is inferred from the VISIR observations in the direction of the major axis, which represents a projected upper limit. Assuming that the dust shell expands in that direction as fast as the low-excitation slow ejecta detected in spectroscopy, this yields a lower limit distance to V1280 Sco of 1kpc; however, the systematic errors remain large due to the complex shape and velocity field of the dusty ejecta. The dust seems to reside essentially in the polar caps and no infrared flux is detected in the equatorial regions in the latest dataset. This may imply that the mass-loss was dominantly polar

    The Moral Resilience of Young People Who Care

    Get PDF
    This paper draws on findings from a qualitative study of the social wellbeing of young people caring for a close family member. The research makes a novel contribution to the international literature by examining the moral resilience of young adult carers. Focus groups or individual, semi-structured interviews were undertaken with fifteen young people in South-East England during 2018–2019. The paper explores whether young people with a seriously ill or disabled family member define and conduct themselves in moral terms and how they respond to the moral challenges of a caring life. It was found that the participants saw moral value in their caring role and their actions reflected a desire to provide compassionate care. Previous research into young adult carers had indicated that the caring role stimulated their political consciousness, but this study suggests that the role also strengthens their moral consciousness. However, designating girls as carers in early life shifts the moral responsibility to females and compounds gender inequity in caring. Hence, there is a need to address social and gender inequalities in care. In addition, healthcare professionals should recognise when statutory input is necessary to facilitate young people’s broader lifeplans

    High school boys' and girls' writing conceptions and writing self-efficacy beliefs : what is their role in writing performance?

    Get PDF
    ABSTRACT: This study investigated the conceptions about writing and writing self-efficacy beliefs held by high school students in relation to the students’ gender as well as their associations with writing achievement. The results show that female students have more sophisticated writing conceptions than their male counterparts but no gender differences were found in writing self-efficacy beliefs. In addition, results reveal that writing self-efficacy beliefs and gender play an important role in predicting writing performance and that writing performance is moderated by students’ writing conceptions. Educational implications and further research are discussed

    Informed design of educational technology for teaching and learning? Towards an evidence-informed model of good practice

    Get PDF
    The aim of this paper is to model evidence-informed design based on a selective critical analysis of research articles. We draw upon findings from an investigation into practitioners’ use of educational technologies to synthesise and model what informs their designs. We found that practitioners’ designs were often driven by implicit assumptions about learning. These shaped both the design of interventions and the methods sought to derive evaluations and interpret the findings. We argue that interventions need to be grounded in better and explicit conceptualisations of what constitutes learning in order to have well-informed designs that focus on improving the quality of student learning
    • …
    corecore