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We present observations of SN 2015bn (= PS15ae = CSS141223-113342+004332 = MLS150211-113342+004333), a Type I superluminous supernova (SLSN) at redshift z = 0.1136. As well as being one of the closest SLSNe I yet discovered, it is intrinsically brighter (M U ≈ −23.1) and in a fainter galaxy (M B ≈ −16.0) than other SLSNe at z ∼ 0.1. We used this opportunity to collect the most extensive dataset for any SLSN I to date, including densely-sampled spectroscopy and photometry, from the UV to the NIR, spanning −50 to +250 days from optical maximum. SN 2015bn fades slowly, but exhibits surprising undulations in the light curve on a timescale of 30-50 days, especially in the UV. The spectrum shows extraordinarily slow evolution except for a rapid transformation between +7 and +20-30 days. No narrow emission lines from slow-moving material are observed at any phase. We derive physical properties including the bolometric luminosity, and find slow velocity evolution and non-monotonic temperature and radial evolution. A deep radio limit rules out a healthy off-axis gamma-ray burst, and places constraints on the pre-explosion mass loss. The data can be consistently explained by a 10 M stripped progenitor exploding with ∼ 10 51 erg kinetic energy, forming a magnetar with arXiv:1603.04748v3 [astro-ph.SR] 22 Jul 2016 a spin-down timescale of ∼ 20 d (thus avoiding a gamma-ray burst) that reheats the ejecta and drives ionization fronts. The most likely alternative scenario -interaction with ∼ 20 M of dense, inhomogeneous circumstellar material -can be tested with continuing radio follow-up.

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People’s life expectancy is increasing throughout the world as a result of improved living standards and medical advances. The natural ageing process is accompanied by physiological changes which can have significant consequences for mobility. As a consequence, older people tend to make fewer journeys than other adults and may change their transport mode. Access to public transport can help older people to avail themselves of goods, services, employment and other activities. With the current generation of older people being more active than previous generations of equivalent age, public transport will play a crucial role in maintaining their active life style even when they are unable to drive. Hence, public transport is important to older people’s quality of life, their sense of freedom and independence. Within the European Commission funded GOAL (Growing Older and staying mobile) project, the requirements of older people using public transport were studied in terms of four main issues: Affordability, availability, accessibility and acceptability. These requirements were then analysed in terms of five different profiles of older people defined within the GOAL project – ‘Fit as a Fiddle’, ‘Hole in the Heart’, ‘Happily Connected’, An ‘Oldie but a Goodie’ and ‘Care-Full’. On the basis of the analysis the paper brings out some areas of knowledge gaps and research needed to make public transport much more attractive and used by older people in the 21st century.

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We study the galaxy populations in 74 Sunyaev Zeldovich Effect (SZE) selected clusters from the South Pole Telescope (SPT) survey that have been imaged in the science verification phase of the Dark Energy Survey (DES). The sample extends up to z ∼ 1.1 with 4 × 10 14 M ≤ M 200 ≤ 3 × 10 15 M . Using the band containing the 4000 Å break and its redward neighbor, we study the color-magnitude distributions of cluster galaxies to ∼ m * + 2, finding: (1) the intrinsic rest frame g − r color width of the red sequence (RS) population is ∼0.03 out to z ∼ 0.85 with a preference for an increase to ∼ 0.07 at z = 1 and (2) the prominence of the RS declines beyond z ∼ 0.6. The spatial distribution of cluster galaxies is well described by the NFW profile out to 4R 200 with a concentration of c g = 3.59 +0.20 −0.18 , 5.37 +0.27 −0.24 and 1.38 +0.21 −0.19 for the full, the RS and the blue non-RS populations, respectively, but with ∼ 40% to 55% cluster to cluster variation and no statistically significant redshift or mass trends. The number of galaxies within the virial region N 200 exhibits a mass trend indicating that the number of galaxies per unit total mass is lower in the most massive clusters, and shows no significant redshift trend. The red sequence (RS) fraction within R 200 is (68 ± 3)% at z = 0.46, varies from ∼55% at z = 1 to ∼80% at z = 0.1, and exhibits intrinsic variation among clusters of ∼ 14%. We discuss a model that suggests the observed redshift trend in RS fraction favors a transformation timescale for infalling field galaxies to become RS galaxies of 2 to 3 Gyr.

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