3,111 research outputs found

    Informal learning as a catalyst for social justice in music

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    This chapter considers social justice in relation to the incorporation of a set of informal learning practices within the secondary school music classroom and teacher education. We interpret Nancy Fraser’s view of social justice as “parity of participation” in order to suggest that the dialogical approach of informal music learning practices can potentially promote such participatory parity. We then examine Paulo Freire’s concept of critical pedagogy, which emphasizes the need for teachers and students to participate together in the learning process so as to enhance critical consciousness. Through an application of Green’s theory of musical meaning we suggest that critical consciousness in music can be aided through a deeper understanding of music’s sonic materials and their inter-relations. Informal learning in the music classroom may promote both parity of participation and critical consciousness, with the potential to lead to a liberating musical experience

    Adaptation to climate change and climate variability: Do it now or wait and see?

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    As growing attention is paid to climate change adaptation as an actual policy issue, the significant meaning of climate variability in adaptation decisions is beginning to be recognized. By using a real option framework, we shed light on how climate change and climate variability affect individuals' (farmers') investment decisions with regard to adaptation. As a plausible case in which the delay carries policy implications, we investigate farmers' choices when adaptation involves the use of an open-access resource (water). The results show that uncoordinated farmers with a high risk aversion may under-adapt while farmers with a low risk aversion would over-adapt under the same conditions. Private adaptation should be supported or discouraged accordingly if farmers are not convinced about the possibilities of collective resource management in the long run

    A hard X-ray polarimeter designed for transient astrophysical sources

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    — This paper discusses the latest progress in the development of GRAPE (Gamma-Ray Polarimeter Experiment), a hard X-ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X-rays in the 50-300 keV energy range. We are particularly interested in X-rays that are emitted from solar flares and gamma-ray bursts (GRBs). Accurately measuring the polarization of the emitted radiation from these sources will lead, to a better understating of both the emission mechanisms and source geometries. The GRAPE design consists of an array of plastic scintillators surrounding a central high-Z crystal scintillator. We can monitor individual Compton scatters that occur in the plastics and determine whether the photon is photo absorbed by the high-Z crystal or not. A Compton scattered photon that is immediately photo absorbed by the high-Z crystal constitutes a valid event. These valid events provide us with the interaction locations of each incident photon and ultimately produces a modulation pattern for the Compton scattering of the polarized radiation. Comparing with Monte Carlo simulations of a 100% polarized beam, the level of polarization of the measured beam can then be determined. The complete array is mounted on a flat-panel multi-anode photomultiplier tube (MAPMT) that can measure the deposited energies resulting from the photon interactions. The design of the detector allows for a large field-ofview (\u3e π steradian), at the same time offering the ability to be close-packed with multiple modules in order to reduce deadspace. We plan to present in this paper the latest laboratory results obtained from GRAPE using partially polarized radiation sources

    The Prograde Orbit of Exoplanet TrES-2b

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    We monitored the Doppler shift of the G0V star TrES-2 throughout a transit of its giant planet. The anomalous Doppler shift due to stellar rotation (the Rossiter-McLaughlin effect) is discernible in the data, with a signal-to-noise ratio of 2.9, even though the star is a slow rotator. By modeling this effect we find that the planet's trajectory across the face of the star is tilted by -9 +/- 12 degrees relative to the projected stellar equator. With 98% confidence, the orbit is prograde.Comment: ApJ, in press [15 pages

    Prospects for GRB Polarimetry with GRAPE

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    This paper discusses the latest progress in the development of GRAPE (Gamma‐Ray Polarimeter Experiment), a hard X‐ray Compton Polarimeter. The purpose of GRAPE is to measure the polarization of hard X‐rays in the 50–300 keV energy range. We are particularly interested in X‐rays that are emitted from solar flares and gamma‐ray bursts (GRBs). Accurately measuring the polarization of the emitted radiation from these sources will lead to a better understating of both the emission mechanisms and source geometries. The GRAPE design consists of an array of plastic scintillators surrounding a central high‐Z crystal scintillator. We can monitor individual Compton scatters that occur in the plastics and determine whether the photon is photo absorbed by the high‐Z crystal or not. A Compton scattered photon that is immediately photo absorbed by the high‐Z crystal constitutes a valid event. These valid events provide us with the interaction locations of each incident photon and ultimately produces a modulation pattern for the Compton scattering of the polarized radiation. Comparing with Monte Carlo simulations of a 100% polarized beam, the level of polarization of the measured beam can then be determined. The complete array is mounted on a flat‐panel multi‐anode photomultiplier tube (MAPMT) that can measure the deposited energies resulting from the photon interactions. The design of the detector allows for a large field‐of‐view (\u3e π steradian), at the same time offering the ability to be close‐packed with multiple modules in order to reduce deadspace. We present in this paper the latest laboratory results obtained from GRAPE using partially polarized radiation sources along with a brief description of our future plans for the GRAPE design

    CdZnTe background measurement at balloon altitudes with an active BGO shield

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    We report results of an experiment conducted in May 1997 to measure CdZnTe background and background reduction schemes in space flight conditions similar to those of proposed hard x-ray astrophysics missions. A 1 cm^2 CdZnTe detector was placed adjacent to a thick BGO anticoincidence shield and flown piggy backed onto the EXITE2 scientific balloon payload. The planar shield was designed to veto background counts produced by local gamma-ray production in passive material and neutron interactions in the detector. The CdZnTe and BGO were partially surrounded by a Pb-Sn-Cu shield to approximate the grammage of an x-ray collimator, although the field of view was still approximately 2 π sr. At an altitude of 127000 feet we find a reduction in background by a factor of 6 at 100 keV. The non-vetoed background is 9 X 10^(-4) cts cm^(-2) s^(-1) at 100 keV, about a factor of 2 higher than that of the collimated (4.5° FWHM) EXITE2 phoswich detector. We compare our recorded spectrum with that expected from simulations using GEANT and find agreement within a factor of 2 between 30 and 300 keV. We also compare our results with those of previous experiments using passive lead and active NaI shields, and discus possible active shielding schemes in future astronomy mission employing large arrays of CdZnTe detectors
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