36,063 research outputs found
A Herschel resolved far-infrared dust ring around HD 207129
Context. Dusty debris discs around main sequence stars are thought to be the result of continuous collisional grinding of planetesimals in the system. The majority of these systems are unresolved and analysis of the dust properties is limited by the lack of information regarding the dust location.
Aims. The Herschel DUNES key program is observing 133 nearby, Sun-like stars (<20 pc, FGK spectral type) in a volume limited survey to constrain the absolute incidence of cold dust around these stars by detection of far infrared excess emission at flux levels comparable to the Edgeworth-Kuiper belt (EKB).
Methods. We have observed the Sun-like star HD 207129 with Herschel PACS and SPIRE. In all three PACS bands we resolve a ring-like structure consistent with scattered light observations. Using α Boötis as a reference point spread function (PSF), we deconvolved the images, clearly resolving the inner gap in the disc at both 70 and 100 μm.
Results. We have resolved the dust-producing planetesimal belt of a debris disc at 100 μm for the first time. We measure the radial profile and fractional luminosity of the disc, and compare the values to those of discs around stars of similar age and/or spectral type, placing this disc in context of other resolved discs observed by Herschel/DUNES
Resource Letter: Gravitational Lensing
This Resource Letter provides a guide to a selection of the literature on
gravitational lensing and its applications. Journal articles, books, popular
articles, and websites are cited for the following topics: foundations of
gravitational lensing, foundations of cosmology, history of gravitational
lensing, strong lensing, weak lensing, and microlensing.Comment: Resource Letter, 2012, in press
(http://ajp.dickinson.edu/Readers/resLetters.html); 21 pages, no figures;
diigo version available at
http://groups.diigo.com/group/gravitational-lensin
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Event Processing through naming: Investigating event focus in two people with aphasia
Some people with aphasia may have trouble with verbs because of fundamental difficulties in processing situations in a way that maps readily onto language. This paper describes a novel assessment, the Order of Naming Test, that explores the conceptual processing of events through the order in which people name the entities involved. The performance of non-brain damaged control participants is described. The responses of two people with non-fluent aphasia are then discussed. Both 'Helen' and 'Ron' showed significant difficulty with verbs and sentences. Ron also had trouble on a range of tasks tapping aspects of event processing, despite intact non-verbal cognition. While Helen's performance on the Order of Naming Test was very similar to the controls, Ron's differed in a number of respects, suggesting that he was less focused on the main participant entities. However, certain aspects of his response pointed at covert event processing abilities that might be fruitfully exploited in therapy
Whole body interaction
In this workshop we explore the notation of whole body interaction. We bring together different disciplines to create a new research direction for study of this emerging form of interaction
Listening to John W. Davis
From the Library is a new section in The Journal that will reprint the best that has been written about appellate practice and the appellate process. The first piece features timeless advice about oral argument by John W. Davis. Davis was a country lawyer, law teacher, state legislator and congressman, Solicitor General of the United States, Ambassador to the Court of St. James\u27s, Democratic candidate for President in 1924, and managing partner of a New York City law firm
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