The AIROPA software package - Milestones for testing general relativity in the strong gravity regime with AO

General relativity can be tested in the strong gravity regime by monitoring stars orbiting the supermassive black hole at the Galactic Center with adaptive optics. However, the limiting source of uncertainty is the spatial PSF variability due to atmospheric anisoplanatism and instrumental aberrations. The Galactic Center Group at UCLA has completed a project developing algorithms to predict PSF variability for Keck AO images. We have created a new software package (AIROPA), based on modified versions of StarFinder and Arroyo, that takes atmospheric turbulence profiles, instrumental aberration maps, and images as inputs and delivers improved photometry and astrometry on crowded fields. This software package will be made publicly available soon

The AIROPA software package - Milestones for testing general relativity in the strong gravity regime with AO

General relativity can be tested in the strong gravity regime by monitoring stars orbiting the supermassive black hole at the Galactic Center with adaptive optics. However, the limiting source of uncertainty is the spatial PSF variability due to atmospheric anisoplanatism and instrumental aberrations. The Galactic Center Group at UCLA has completed a project developing algorithms to predict PSF variability for Keck AO images. We have created a new software package (AIROPA), based on modified versions of StarFinder and Arroyo, that takes atmospheric turbulence profiles, instrumental aberration maps, and images as inputs and delivers improved photometry and astrometry on crowded fields. This software package will be made publicly available soon

Urban planning after the Black Death: townscape transformations in later-medieval England (1350-1530)

ABSTRACT:This article offers a reconsideration of planning and development in English towns and cities after the Black Death (1348). Conventional historical accounts have stressed the occurrence of urban ‘decay’ in the later fourteenth and fifteenth centuries. Here, instead, a case is made that after 1350 urban planning continued to influence towns and cities in England through the transformation of their townscapes. Using the conceptual approaches of urban morphologists in particular, the article demonstrates that not only did the foundation of new towns and creation of new suburbs characterize the period 1350–1530, but so too did the redevelopment of existing urban landscapes through civic improvements and public works. These reveal evidence for the particular ‘agents of change’ involved in the planning and development process, such as surveyors, officials, patrons and architects, and also the role played by maps and drawn surveys. In this reappraisal, England's urban experiences can be seen to have been closely connected with those instances of urban planning after the Black Death occurring elsewhere in contemporary continental Europe.</jats:p

Paysage urbain en transition à Coventry : processus de formation et de transformation urbaine dans une cité médiévale anglaise

English historiography on the development of urban spaces during the medieval era is dominated, especially among historians and archaeologists, by the persistence of the organic growth theory, which it is necessary to challenge. The geographer M. R. G. Conzen did much to challenge this model through his technique of analysing town and city maps, whilst at the same time opening up debate on the process of medieval urban formation and transformation that conventional documentary sources often hide. By using the Conzen method, the map of the city of Coventry reveals the medieval history of its morphogenesis. The examination focuses on the stages of urban formation, in particular on the phenomenon of suburbanisation and the different processes of urban transformation.L’historiographie anglaise sur l’évolution de l’espace urbain à l’époque médiévale est dominée, en particulier chez les historiens et les archéologues, par la persistance de la théorie de la croissance organique (organic growth theory) qu’il faut remettre en question. Le géographe M. R. G. Conzen a fait beaucoup pour remettre en question ce modèle par sa technique d’analyse des plans de ville, tandis qu’en même temps il a ouvert la réflexion sur le processus des formation et transformation urbaines médiévales que les sources documentaires conventionnelles cachent souvent. En utilisant la méthode de Conzen, le plan de la ville de Coventry révèle l’histoire médiévale de sa morphogenèse. L’examen porte sur les étapes de la formation urbaine, en particulier le phénomène de suburbanisation et les différents processus de transformation urbaine.La historiografía inglesa acerca de la evolución del espacio urbano en la época medieval está dominada, particularmente entre los historiadores y los arqueólogos, por la persistencia de la teoría del crecimiento orgánico (organic growth theory), la cual hay que cuestionar. El geógrafo M. R. G. Conzen ha contribuido al debate sobre este modelo a través de la técnica del análisis de los planos de la ciudad, mientras que, al mismo tiempo, ha incitado a la reflexión sobre los procesos de formación y de transformación urbanas en la Edad Media, generalmente ausentes en las fuentes documentales convencionales. Utilizando el método de Conzen, el plano de la ciudad de Coventry revela la historia medieval de su morfogénesis. Su examen trata las etapas de la formación urbana, en particular el fenómeno de sub-urbanización y los diferentes procesos de transformación de la ciudad.Lilley Keith D. Paysage urbain en transition à Coventry : processus de formation et de transformation urbaine dans une cité médiévale anglaise. In: Archéologie du Midi médiéval. Tome 34, 2016. pp. 147-161