14 resultados para Lagoa Nova quarter
Resumo:
Nova V458 Vul erupted on 2007 August 8 and reached a visual magnitude of 8.1 a few days later. Ha images obtained 6 weeks before the outburst as part of the IPHAS Galactic plane survey reveal an 18th magnitude progenitor surrounded by an extended nebula. Subsequent images and spectroscopy of the nebula reveal an inner nebular knot increasing rapidly in brightness due to flash ionization by the nova event. We derive a distance of 13 kpc based on light travel time considerations, which is supported by two other distance estimation methods. The nebula has an ionized mass of 0.2 Msolar and a low expansion velocity: this rules it out as ejecta from a previous nova eruption, and is consistent with it being a ~14,000 year old planetary nebula, probably the product of a prior common envelope (CE) phase of evolution of the binary system. The large derived distance means that the mass of the erupting WD component of the binary is high. We identify two possible evolutionary scenarios, in at least one of which the system is massive enough to produce a Type Ia supernova upon merging.
Resumo:
This paper investigates the limitations of postcolonial planning practices that aimed to modernise Cairo’s urban spaces during Gamal Abdel Nasser rule (1952–70). Following the Free Officers revolution of 1952, ambition to display urban order through forceful change in the city’s built environment was in action. Nasser’s visions of modernity were explicit in a series of attempts to reshape several prime locations in central Cairo, which included the old traditional waterfront quarter, in Bulaq Abul Ela. An analysis of the Bulaq planning scheme drafted in 1966 reveals insights into how notions of order were spatialised to integrate with Cairo’s complex urban fabric. The official plans to regularise Bulaq also strongly demonstrates how this was a top-down, centralised process in terms of governance, with full utilisation of state resources, namely the military and the media. From a wider perspective, planning practices under Nasser demonstrated an evident break with the past to eliminate memories of colonisation and disorder. Drawing on original resources, archival material, meeting minutes and maps of this historical but dilapidated quarter of Cairo, this paper gives an insight into how Nasser’s government attempted to convey a sense of order in a revolutionary country without, however, having an understanding of order as a coherent, multilayered and sequential process of change.
Resumo:
The POINT-AGAPE (Pixel-lensing Observations with the Isaac Newton Telescope-Andromeda Galaxy Amplified Pixels Experiment) survey is an optical search for gravitational microlensing events towards the Andromeda galaxy (M31). As well as microlensing, the survey is sensitive to many different classes of variable stars and transients. In our first paper of this series, we reported the detection of 20 classical novae (CNe) observed in Sloan r' and i' passbands.
Resumo:
The POINT-AGAPE (Pixel-lensing Observations with the Isaac Newton Telescope-Andromeda Galaxy Amplified Pixels Experiment) survey is an optical search for gravitational microlensing events towards the Andromeda galaxy (M31). As well as microlensing, the survey is sensitive to many different classes of variable stars and transients. Here we describe the automated detection and selection pipeline used to identify M31 classical novae (CNe) and we present the resulting catalogue of 20 CN candidates observed over three seasons. CNe are observed both in the bulge region as well as over a wide area of the M31 disc. Nine of the CNe are caught during the final rise phase and all are well sampled in at least two colours. The excellent light-curve coverage has allowed us to detect and classify CNe over a wide range of speed class, from very fast to very slow. Among the light curves is a moderately fast CN exhibiting entry into a deep transition minimum, followed by its final decline. We have also observed in detail a very slow CN which faded by only 0.01 mag d(-1) over a 150-d period. We detect other interesting variable objects, including one of the longest period and most luminous Mira variables. The CN catalogue constitutes a uniquely well-sampled and objectively-selected data set with which to study the statistical properties of CNe in M31, such as the global nova rate, the reliability of novae as standard-candle distance indicators and the dependence of the nova population on stellar environment. The findings of this statistical study will be reported in a follow-up paper.
Resumo:
This article examines the role of tourism as a motive and mechanism for change in contemporary cities, considering how the theming of space with tourists in mind necessarily involves other kinds of spatial and social transformation, and asking what role actual and hypothetical tourists play in local contests over space and representation. Looking closely at Belfast’s Gaeltacht Quarter provides an insight into how global fashions in place marketing, tourism and minority language promotion intersect with the particularities of areas to which they are applied. This paper argues that the superficially value-neutral, internationally recognisable language of economic
development can be used both as a means of transcending, and a means of
strategically negotiating, intense struggles over space, identity and status.
Resumo:
This paper considers the recent proliferation of Belfast‘s =Quarters‘ as part of global trends towards the theming of city space, and as a response to the particular situation of Belfast at the beginning of the twenty-first century. It focuses on the Gaeltacht Quarter, a site that exemplifies the difficulty of applying the internationally popular model of cultural difference as a resource for the production of tourist revenue to the context of contested cities. The =quartering‘ of Belfast is represented as a response to post-industrial and post-conflict predicaments this city shares with many others. I consider how the urban context is sometimes exploited, as in exhortations to investors and tourists to contribute to Belfast‘s transformation from =a city of two halves‘ to =a city of seven quarters‘, and sometimes obscured, as in the recent re-invention of the Quarters as remnants of the city‘s distant past.
Resumo:
The UV spectra of nova-like variables are dominated by emission from the accretion disk, modified by scattering in a wind emanating from the disk. Here, we model the spectra of RW Tri and UX UMa, the only two eclipsing nova-like variables which have been observed with the Hubble Space Telescope in the far-ultraviolet, in an attempt to constrain the geometry and the ionization structure of their winds. Using our Monte Carlo radiative transfer code, we computed spectra for simply parameterized axisymmetric biconical outflow models and were able to find plausible models for both systems. These reproduce the primary UV resonance lines-N v, Si iv, and C iv-in the observed spectra in and out of eclipse. The distribution of these ions in the wind models is similar in both cases as is the extent of the primary scattering regions in which these lines are formed. The inferred mass-loss rates are 6%-8% of the mass accretion rates for the systems. We discuss the implication of our point models for our understanding of accretion disk winds in cataclysmic variables. © 2010. The American Astronomical Society. All rights reserved.
Resumo:
We present observations of the unusual optical transient SN 2010U, including spectra taken 1.03 days to 15.3 days after maximum light that identify it as a fast and luminous Fe II type nova. Our multi-band light curve traces the fast decline (t 2 = 3.5 ± 0.3 days) from maximum light (MV = -10.2 ± 0.1 mag), placing SN 2010U in the top 0.5% of the most luminous novae ever observed. We find typical ejecta velocities of ≈1100 km s-1 and that SN 2010U shares many spectral and photometric characteristics with two other fast and luminous Fe II type novae, including Nova LMC 1991 and M31N-2007-11d. For the extreme luminosity of this nova, the maximum magnitude versus rate of decline relationship indicates a massive white dwarf (WD) progenitor with a low pre-outburst accretion rate. However, this prediction is in conflict with emerging theories of nova populations, which predict that luminous novae from massive WDs should preferentially exhibit an alternate spectral type (He/N) near maximum light.
Resumo:
This paper examines a place-making project in post-conflict Belfast, analyzing efforts to transform an area which has often been used as a byword for militant Irish nationalism and social deprivation into an inclusive, vibrant tourist destination and cultural hub themed around the Irish language (called the "Gaeltacht Quarter‟). The antagonistic and territorial assumptions about place that characterize divided cities now co-exist with global trends towards the commodification of difference as recreation or spectacle, and longstanding struggles over the representation of contested identities are intertwined with the struggle to compete for international tourism and investment. The proliferation of officially themed quarters in many cities across the world reflects the enthusiasm with which planning authorities have embraced the vision of difference as a benign resource for the creation of tourist revenue. Yet, analysis of „quartering‟ processes reveals that such commodification does not neutralise or evade the political potency of naming, representing and delimiting cultural difference. Indeed, this paper argues that such projects offer a valuable insight into the inseparable roles of physical and representational space as both loci and catalysts of contestation in urban conflicts. Bringing together a wide range of public and private interest groups, projects redefining parts of Belfast as distinctive quarters have been explicitly linked with efforts to deterritorialize the city. The creation of bounded, themed spaces as an attempt to leave behind the ethno-sectarian geographical segregation that parts of Belfast still experience has its particular ironies, but is in many ways typical of contemporary trends in urban planning. The Gaeltacht Quarter exemplifies both the importance and the challenge of representation within cities where culturally distinguishing features have acted as markers of violent division, and where negotiations about how to successfully encompass difference necessarily address multiple local and international audiences simultaneously.
Resumo:
Over time Belfast has been well researched as a site of ethnosectarian conflict, segregation and fear see (Boal et al 1976) and (Gaffiken and Morrisey 2011). The study of socio-spatial patterns of ‘ethnocracy’ is useful, but this article will argue how it is equally important to understand local forms of urban restructuring in terms of global processes that are linked to neoliberalism. To better understand the neoliberal urbanisation of Belfast this article is organised into two parts. The first part will demonstrate how the Northern Ireland State has sought legitimacy in the free market as ‘therapy’ for the production of neutral socio-spatial formations such as the Cathedral Quarter. Secondly it will examine this performance of neoliberal urbanism, as it ‘actually exists’ and demonstrate how market-led renewal has been extended through the clustering and non-sectarian interests, ‘soft’ arrangements of urban governance, cultural re-branding strategies, economic development incentives, and the development of various flagship projects. Critically this place-based grounding of neoliberalism is useful, as it also allows for the contestations of neoliberal urbanism to become real rather than just theoretical. The second part of the article will draw attention to the responses of local, and sometimes marginal, interests that have looked to challenge, adapt and, at times, divert the extension of market-led renewal. To be clear, this article does not want to overstate the performance of such interests. Nor does it want to claim that they significantly impact or obstruct the wider neoliberal urbanisation of Belfast. Instead it is interested in their behaviours and their different methods of working to explore what may be constituted as ‘alternative’, at least in the locality of the Cathedral Quarter. By studying how and why these interests have responded to the extension of neoliberal urbanism over time, it may just be possible to provide a better platform to articulate what more progressive forms of urban resistance might look like.