5,051 research outputs found

    Potential model calculations and predictions for heavy quarkonium

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    We investigate the spectroscopy and decays of the charmonium and upsilon systems in a potential model consisting of a relativistic kinetic energy term, a linear confining term including its scalar and vector relativistic corrections and the complete perturbative one-loop quantum chromodynamic short distance potential. The masses and wave functions of the various states are obtained using a variational technique, which allows us to compare the results for both perturbative and nonperturbative treatments of the potential. As well as comparing the mass spectra, radiative widths and leptonic widths with the available data, we include a discussion of the errors on the parameters contained in the potential, the effect of mixing on the leptonic widths, the Lorentz nature of the confining potential and the possible ccˉc\bar{c} interpretation of recently discovered charmonium-like states.Comment: Physical Review published versio

    Enhancing Perceptual Attributes with Bayesian Style Generation

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    Deep learning has brought an unprecedented progress in computer vision and significant advances have been made in predicting subjective properties inherent to visual data (e.g., memorability, aesthetic quality, evoked emotions, etc.). Recently, some research works have even proposed deep learning approaches to modify images such as to appropriately alter these properties. Following this research line, this paper introduces a novel deep learning framework for synthesizing images in order to enhance a predefined perceptual attribute. Our approach takes as input a natural image and exploits recent models for deep style transfer and generative adversarial networks to change its style in order to modify a specific high-level attribute. Differently from previous works focusing on enhancing a specific property of a visual content, we propose a general framework and demonstrate its effectiveness in two use cases, i.e. increasing image memorability and generating scary pictures. We evaluate the proposed approach on publicly available benchmarks, demonstrating its advantages over state of the art methods.Comment: ACCV-201

    CCAT

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    Star formation, which drives the evolution of baryonic matter in the universe, occurs in the densest regions of the interstellar medium. As a result much of the emergent short wavelength radiation, UV to near IR, is absorbed by intervening dust and reradiated at longer wavelengths, far IR and subillimeter. Indeed the energy density of post primordial extragalactic light is divided equally between these short and long wavelengths, indicating equal amounts of radiation have passed through dusty and optically transparent environments over cosmic time. Comprehensive understanding of the processes of galaxy, star, and planetary formation requires, therefore, high sensitivity and high angular resolution observations, particularly surveys, in the far IR and submillimeter. A consortium led by Cornell and Caltech with JPL is now jointly planning the construction of a 25 m diameter telescope for submillimeter astronomy on a high mountain in northern Chile. This CCAT will combine high sensitivity, a wide field of view, and a broad wavelength range to provide an unprecedented capability for deep, large area, multi-color submillimeter surveys to complement narrow field, high resolution studies with ALMA. CCAT observations will address fundamental themes in contemporary astronomy, notably the formation and evolution of galaxies, the nature of the dark matter and dark energy that comprise most of the content of the universe, the formation of stars and planets, the conditions in circumstellar disks, and the conditions during the early history of the Solar system. The candidate CCAT site, at 5600m in northern Chile, enjoys superb observing conditions. To accommodate large format bolometer cameras, CCAT is designed with a 20 arcmin field of view. CCAT will incorporate closed loop active control of its segmented primary mirror to maintain a half wavefront error of 10 μm rms or less for the entire telescope. Instrumentation under consideration includes both short (650 μm–200 μm) and long (2 mm–750 μm) wavelength bolometer cameras, direct detection spectrometers, and heterodyne receiver arrays. In addition to Cornell and Caltech with JPL, the University of Colorado, the Universities of British Columbia and of Waterloo, the UK Astronomy Technology Centre on behalf of the UK community, and the Universities of Cologne and of Bonn have joined the CCAT consortium. When complete, CCAT will be the largest and most sensitive facility of its class as well as the highest altitude astronomical facility on Earth

    Tranformation of Neurospora pyr-4 with defective donor genes

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    Using the Vollmer/Orbach transformation protocol, transformation frequencies of a pyr-4 (OMP decarboxylase) strain of Neurospora crassa of circa 10(3)/µg are routinely achievable. At these levels of transformation, it is feasible to screen out ectopic integrations and look specifically for homologous integration events. Homologous integrants were sought by transforming a pyr-4 recipient with interrupted or incomplete copies of the cloned pyr-4 gene derived from the pyr+ clone in plasmid pFB6, selecting by complementation of the pyrimidine auxotrophy in the recipien

    Variation of Molecular Line Ratios and Cloud Properties in the Arp 299 Galaxy Merger

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    High resolution observations of 12CO (2.''3), 13CO (3.''9), and HCN (5.''4) J=1--0 in the galaxy merger Arp 299 (IC 694 and NGC 3690) show the line ratios vary dramatically across the system. The 12CO/13CO ratio is unusually large, 60 +- 15, at the IC 694 nucleus, where 12CO emission is very strong, and much smaller, 10 +- 3, in the southern extended disk of that galaxy. Elsewhere, the 12CO/13CO line ratio is 5-20, typical of spiral galaxies. The line ratio variation in the overlap between the two galaxies is smaller, ranging from 10 +- 3 in the east to 20 +- 4 in the west. The 12CO/HCN line ratio also varies across Arp 299, although to a lesser degree. HCN emission is bright towards each galaxy nucleus and in the extranuclear region of active star formation; it was not detected in the IC 694 disk, or the eastern part of the overlap region, leading to lower limits of 25 and 20 respectively. By contrast, at the nuclei of IC 694 and NGC 3690 the ratios are 9 +- 1 and 14 +- 3 respectively. In the western part of the overlap region it is 11 +- 3.Comment: 16 pages, 4 postscript figures, to appear in ApJ Letter

    An evaluation of geomagnetic harmonic series for 1100 kilometers altitude

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    Geomagnetic harmonic series evaluation for 1100 kilometers altitude using satellite observation

    Parent-child interaction in Nigerian families: conversation analysis, context and culture

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    This paper uses a conversation analysis (CA) approach to explore parent child interaction (PCI) within Nigerian families. We illustrate how speech and language therapists (SLTs), by using CA, can tailor recommendations according to the interactional style of each individual family that are consonant with the family’s cultural beliefs. Three parent-child dyads were videoed playing and talking together in their home environments. The analysis uncovered a preference for instructional talk similar to that used in the classroom. Closer examination revealed that this was not inappropriate when considering the context of the activities and their perceived discourse role. Furthermore, this was not necessarily at the expense of responsivity or semantic contingency. The preference for instructional talk appeared to reflect deeply held cultural beliefs about the role of adults and children within the family and it is argued that the cultural paradigm is vitally important to consider when evaluating PCI. Given a potential risk that such young children may be vulnerable in terms of language difficulties, we offer an example of how PCI can be enhanced to encourage language development without disrupting the naturally occurring talk or the underlying purpose of the interaction

    The scaler magnetic intensity at 1100 kilometers in middle and low latitudes

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    Satellite borne magnetometer for measuring scalar magnetic intensities in middle and low latitudes at 1100 km altitud

    Stability of the Submillimeter Brightness of the Atmosphere Above Mauna Kea, Chajnantor and the South Pole

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    The summit of Mauna Kea in Hawaii, the area near Cerro Chajnantor in Chile, and the South Pole are sites of large millimeter or submillimeter wavelength telescopes. We have placed 860 GHz sky brightness monitors at all three sites and present a comparative study of the measured submillimeter brightness due to atmospheric thermal emission. We report the stability of that quantity at each site.Comment: 6 figure
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