215 research outputs found
Hard Photodisintegration of a Proton Pair
We present a study of high energy photodisintegration of proton-pairs through
the gamma + 3He -> p+p+n channel. Photon energies from 0.8 to 4.7 GeV were used
in kinematics corresponding to a proton pair with high relative momentum and a
neutron nearly at rest. The s-11 scaling of the cross section, as predicted by
the constituent counting rule for two nucleon photodisintegration, was observed
for the first time. The onset of the scaling is at a higher energy and the
cross section is significantly lower than for deuteron (pn pair)
photodisintegration. For photon energies below the scaling region, the scaled
cross section was found to present a strong energy-dependent structure not
observed in deuteron photodisintegration.Comment: 7 pages, 3 figures, for submission to Phys. Lett.
Tune in to your emotions: a robust personalized affective music player
The emotional power of music is exploited in a personalized affective music player (AMP) that selects music for mood enhancement. A biosignal approach is used to measure listeners’ personal emotional reactions to their own music as input for affective user models. Regression and kernel density estimation are applied to model the physiological changes the music elicits. Using these models, personalized music selections based on an affective goal state can be made. The AMP was validated in real-world trials over the course of several weeks. Results show that our models can cope with noisy situations and handle large inter-individual differences in the music domain. The AMP augments music listening where its techniques enable automated affect guidance. Our approach provides valuable insights for affective computing and user modeling, for which the AMP is a suitable carrier application
Rethinking the fall of the planter class
This issue of Atlantic Studies began life as a one-day conference held at Chawton House Library in Hampshire, UK, and funded by the University of Southampton. The conference aimed, like this issue, to bring together scholars currently working on the history of the British West Indian planter class in the eighteenth and nineteenth centuries and to discuss how, when, and why the fortunes of the planters went into decline. As this introduction notes, the difficulties faced by the planter class in the British West Indies from the 1780s onwards were an early episode in a wider drama of decline for New World plantation economies. The American historian Lowell Ragatz published the first detailed historical account of their fall. His work helped to inform the influential arguments of Eric Williams, which were later challenged by Seymour Drescher. Recent research has begun to offer fresh perspectives on the debate about the decline of the planters, and this collection brings together articles taking a variety of new approaches to the topic, encompassing economic, political, cultural, and social histor
Paleobiology of titanosaurs: reproduction, development, histology, pneumaticity, locomotion and neuroanatomy from the South American fossil record
Fil: García, Rodolfo A.. Instituto de Investigación en Paleobiología y Geología. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Salgado, Leonardo. Instituto de Investigación en Paleobiología y Geología. General Roca. Río Negro; ArgentinaFil: Fernández, Mariela. Inibioma-Centro Regional Universitario Bariloche. Bariloche. Río Negro; ArgentinaFil: Cerda, Ignacio A.. Instituto de Investigación en Paleobiología y Geología. Museo Provincial Carlos Ameghino. Cipolletti; ArgentinaFil: Carabajal, Ariana Paulina. Museo Carmen Funes. Plaza Huincul. Neuquén; ArgentinaFil: Otero, Alejandro. Museo de La Plata. Universidad Nacional de La Plata; ArgentinaFil: Coria, Rodolfo A.. Instituto de Paleobiología y Geología. Universidad Nacional de Río Negro. Neuquén; ArgentinaFil: Fiorelli, Lucas E.. Centro Regional de Investigaciones Científicas y Transferencia Tecnológica. Anillaco. La Rioja; Argentin
An Observational Overview of Solar Flares
We present an overview of solar flares and associated phenomena, drawing upon
a wide range of observational data primarily from the RHESSI era. Following an
introductory discussion and overview of the status of observational
capabilities, the article is split into topical sections which deal with
different areas of flare phenomena (footpoints and ribbons, coronal sources,
relationship to coronal mass ejections) and their interconnections. We also
discuss flare soft X-ray spectroscopy and the energetics of the process. The
emphasis is to describe the observations from multiple points of view, while
bearing in mind the models that link them to each other and to theory. The
present theoretical and observational understanding of solar flares is far from
complete, so we conclude with a brief discussion of models, and a list of
missing but important observations.Comment: This is an article for a monograph on the physics of solar flares,
inspired by RHESSI observations. The individual articles are to appear in
Space Science Reviews (2011
The polarized image of a synchrotron-emitting ring of gas orbiting a black hole
High Energy Astrophysic
Constraints on black-hole charges with the 2017 EHT observations of M87*
InstrumentationHigh Energy Astrophysic
- …