168 research outputs found
Hobson’s choice? Constraints on accessing spaces of creative production
Successful creative production is often documented to occur in urban areas that are more likely to be diverse, a source of human capital and the site of dense interactions. These accounts chart how, historically, creative industries have clustered in areas where space was once cheap in the city centre fringe and inner city areas, often leading to the development of a creative milieu, and thereby stimulating further creative production. Historical accounts of the development of creative areas demonstrate the crucial role of accessible low-cost business premises. This article reports on the findings of a case study that investigated the location decisions of firms in selected creative industry sectors in Greater Manchester. The study found that, while creative activity remains highly concentrated in the city centre, creative space there is being squeezed and some creative production is decentralizing in order to access cheaper premises. The article argues that the location choices of creative industry firms are being constrained by the extensive city centre regeneration, with the most vulnerable firms, notably the smallest and youngest, facing a Hobson’s choice of being able to access low-cost premises only in the periphery. This disrupts the delicate balance needed to sustain production and begs the broader question as to how the creative economy fits into the existing urban fabric, alongside the competing demands placed on space within a transforming industrial conurbation
Euclid: Early Release Observations -- Overview of the Perseus cluster and analysis of its luminosity and stellar mass functions
The Euclid ERO programme targeted the Perseus cluster of galaxies, gathering
deep data in the central region of the cluster over 0.7 square degree,
corresponding to approximately 0.25 r_200. The data set reaches a point-source
depth of IE=28.0 (YE, JE, HE = 25.3) AB magnitudes at 5 sigma with a 0.16" and
0.48" FWHM, and a surface brightness limit of 30.1 (29.2) mag per square
arcsec. The exceptional depth and spatial resolution of this wide-field
multi-band data enable the simultaneous detection and characterisation of both
bright and low surface brightness galaxies, along with their globular cluster
systems, from the optical to the NIR. This study advances beyond previous
analyses of the cluster and enables a range of scientific investigations
summarised here. We derive the luminosity and stellar mass functions (LF and
SMF) of the Perseus cluster in the Euclid IE band, thanks to supplementary
u,g,r,i,z and Halpha data from the CFHT. We adopt a catalogue of 1100 dwarf
galaxies, detailed in the corresponding ERO paper. We identify all other
sources in the Euclid images and obtain accurate photometric measurements using
AutoProf or AstroPhot for 138 bright cluster galaxies, and SourceExtractor for
half a million compact sources. Cluster membership for the bright sample is
determined by calculating photometric redshifts with Phosphoros. Our LF and SMF
are the deepest recorded for the Perseus cluster, highlighting the
groundbreaking capabilities of the Euclid telescope. Both the LF and SMF fit a
Schechter plus Gaussian model. The LF features a dip at M(IE)=-19 and a
faint-end slope of alpha_S = -1.2 to -1.3. The SMF displays a low-mass-end
slope of alpha_S = -1.2 to -1.35. These observed slopes are flatter than those
predicted for dark matter halos in cosmological simulations, offering
significant insights for models of galaxy formation and evolution.Comment: Submitted to A&A, 44 pages, 35 figures, Part of the A&A special issue
`Euclid on Sky', which contains Euclid key reference papers and first results
from the Euclid Early Release Observation
Euclid: Early Release Observations -- Programme overview and pipeline for compact- and diffuse-emission photometry
The Euclid ERO showcase Euclid's capabilities in advance of its main mission,
targeting 17 astronomical objects, from galaxy clusters, nearby galaxies,
globular clusters, to star-forming regions. A total of 24 hours observing time
was allocated in the early months of operation, engaging the scientific
community through an early public data release. We describe the development of
the ERO pipeline to create visually compelling images while simultaneously
meeting the scientific demands within months of launch, leveraging a pragmatic,
data-driven development strategy. The pipeline's key requirements are to
preserve the image quality and to provide flux calibration and photometry for
compact and extended sources. The pipeline's five pillars are: removal of
instrumental signatures; astrometric calibration; photometric calibration;
image stacking; and the production of science-ready catalogues for both the VIS
and NISP instruments. We report a PSF with a full width at half maximum of
0.16" in the optical and 0.49" in the three NIR bands. Our VIS mean absolute
flux calibration is accurate to about 1%, and 10% for NISP due to a limited
calibration set; both instruments have considerable colour terms. The median
depth is 25.3 and 23.2 AB mag with a SNR of 10 for galaxies, and 27.1 and 24.5
AB mag at an SNR of 5 for point sources for VIS and NISP, respectively.
Euclid's ability to observe diffuse emission is exceptional due to its extended
PSF nearly matching a pure diffraction halo, the best ever achieved by a
wide-field, high-resolution imaging telescope. Euclid offers unparalleled
capabilities for exploring the LSB Universe across all scales, also opening a
new observational window in the NIR. Median surface-brightness levels of 29.9
and 28.3 AB mag per square arcsec are achieved for VIS and NISP, respectively,
for detecting a 10 arcsec x 10 arcsec extended feature at the 1 sigma level.Comment: Submitted to A&A, 44 pages, 36 figures - Part of the A&A special
issue `Euclid on Sky', which contains Euclid key reference papers and first
results from the Euclid Early Release Observation
Recommended from our members
<i>Euclid</i>: Early Release Observations – Overview of the Perseus cluster and analysis of its luminosity and stellar mass functions★
The Euclid Early Release Observations (ERO) programme targeted the Perseus cluster of galaxies, gathering deep data in the central region of the cluster over 0.7 deg2 , including the cluster core up to 0.25 r 200 . The dataset reaches a point-source depth of IE = 28.0 ( YE , JE , HE = 25.3), AB magnitudes at 5 σ with a 0′′.16 (0′′.48) full width at half maximum (FWHM), and a surface brightness limit of 30.1 (29.2) mag arcsec−2 for radially integrated galaxy profiles. The exceptional depth and spatial resolution of this wide-field multi-band data enable simultaneous detection and characterisation of both bright galaxies and low surface brightness ones, along with their globular cluster systems, from the optical to the near-infrared (NIR). Cluster membership was determined using several methods in order to maximise the completeness and minimise the contamination of foreground and background sources. We adopted a catalogue of 1100 dwarf galaxies, detailed in the corresponding ERO paper, that includes their photometric and structural properties. We identified all other sources in the Euclid images and obtained accurate photometric measurements using AutoProf or AstroPhot for 137 bright cluster galaxies and SourceExtractor for half a million compact sources. This study advances beyond previous analyses of the cluster and enables a range of scientific investigations, which are summarised here. We derived the luminosity and stellar mass functions (LF and SMF) of the Perseus cluster in the Euclid IE band thanks to supplementary u, g, r, i, z , and H α data from the Canada-France-Hawai’i Telescope (CFHT). Our LF and SMF are the deepest recorded for the Perseus cluster, highlighting the groundbreaking capabilities of the Euclid telescope. We fit the LF and SMF with a Schechter plus Gaussian model. The LF features a dip at M ( IE ) ≃ −19 and a faint-end slope of αS ≃ −1.2 to −1.3. The SMF displays a low-mass-end slope of α S ≃ −1.2 to −1.35. These observed slopes are flatter than those predicted for dark matter halos in cosmological simulations, offering significant insights for models of galaxy formation and evolution
Recommended from our members
<i>Euclid</i>: Early Release Observations – Programme overview and pipeline for compact- and diffuse-emission photometry
The Euclid Early Release Observations (ERO) showcase Euclid’s capabilities in advance of its main mission by targeting 17 astronomical objects, including galaxy clusters, nearby galaxies, globular clusters, and star-forming regions. A total of 24 hours of observing time was allocated in the early months of operation, and the scientific community was engaged through an early public data release. We describe the development of the ERO pipeline to create visually compelling images while simultaneously meeting the scientific demands within months of launch by leveraging a pragmatic data-driven development strategy. The pipeline’s key requirements are to preserve the image quality and to provide flux calibration and photometry for compact and extended sources. The pipeline’s five pillars are removal of instrumental signatures, astrometric calibration, photometric calibration, image stacking, and the production of science-ready catalogues for both the VIS and NISP instruments. We report a point spread function (PSF) with a full width at half maximum of 0ʺ.16 in the optical I E -band and 0ʺ.49 in the near-infrared (NIR) bands YE , JE , and HE . Our VIS mean absolute flux calibration is accurate to about 1%, and the accuracy is 10% for NISP due to a limited calibration set; both instruments have considerable colour terms for individual sources. The median depth is 25.3 and 23.2 AB mag with a signal-to-noise ratio (S/N) of ten for galaxies, while it is 27.1 and 24.5 AB mag at an S/N of five for point sources for VIS and NISP, respectively. Euclid’s ability to observe diffuse emission is exceptional due to its extended PSF nearly matching a pure diffraction halo, the best ever achieved by a wide-field high-resolution imaging telescope. Euclid offers unparalleled capabilities for exploring the low-surface brightness (LSB) Universe across all scales, providing high precision within a wide field of view (FoV), and opening a new observational window in the NIR. Median surface-brightness levels of 29.5 and 27.9, AB mag arcsec−2 are achieved for VIS and NISP, respectively, for detecting a 10ʺ × 10ʺ extended feature at the 1 σ level
Euclid: I. Overview of the Euclid mission
The current standard model of cosmology successfully describes a variety of measurements, but the nature of its main ingredients,dark matter and dark energy, remains unknown. Euclid is a medium-class mission in the Cosmic Vision 2015–2025 programme of theEuropean Space Agency (ESA) that will provide high-resolution optical imaging, as well as near-infrared imaging and spectroscopy,over about 14 000 deg² of extragalactic sky. In addition to accurate weak lensing and clustering measurements that probe structureformation over half of the age of the Universe, its primary probes for cosmology, these exquisite data will enable a wide range ofscience. This paper provides a high-level overview of the mission, summarising the survey characteristics, the various data-processingsteps, and data products. We also highlight the main science objectives and expected performance
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Christian Religion and the European Civilizing Process: the views of Norbert Elias and Max Weber compared in the context of the Augustinian and Lucretian traditions.
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