82 research outputs found

    Transitioning Between Audience and Performer: Co-Designing Interactive Music Performances with Children

    Full text link
    Live interactions have the potential to meaningfully engage audiences during musical performances, and modern technologies promise unique ways to facilitate these interactions. This work presents findings from three co-design sessions with children that investigated how audiences might want to interact with live music performances, including design considerations and opportunities. Findings from these sessions also formed a Spectrum of Audience Interactivity in live musical performances, outlining ways to encourage interactivity in music performances from the child perspective

    Hunger is the worst disease: conceptions of poverty and poverty relief in Buddhist social ethics

    Get PDF
    The present work addresses the notions of poverty and poverty relief in Buddhist social and economic ethics, comparing them to current approaches to conceptualizing poverty used in the development community. Given the Buddhist preoccupation with ceasing suffering and removing its causes, and the key Buddhist principle of Right Livelihood that is found in the Ennobling Eightfold Path to enlightenment taught by the Buddha, economic ethics appear to be central to the Buddhist path and a concern for the suffering caused by extreme poverty therefore ought to be a key point of concern in Buddhist ethics. Buddhist ethics has developed into a field of study all its own over the last few decades, addressing issues in applied ethics from bioethics to human rights and environmental concerns, but little has been written by virtually any standard on the important topic of poverty relief. The present work makes a step toward filling that gap by examining relevant passages in the Pāli Canon as well as popular and influential Mahāyāna sūtras to demonstrate that a concern for deprivation or non-voluntary impoverishment is evident in key Buddhist doctrines and teachings from the earliest recorded history of the Buddhist tradition. The thesis further discusses the duties to relieve poverty outlined in Buddhist social ethics as well as the development of Buddhist economics and its critique of dominant mainstream economics. It also offers a comparison of Buddhist conceptions of poverty with contemporary notions of poverty, such as the capabilities approach to poverty developed by Amartya Sen and currently in use by the UNDP. In both of these cases poverty is portrayed in a comprehensive and multi-dimmensional manner which views income as only one aspect of poverty. Additionally, this dissertation examines the contemporary Socially Engaged Buddhist movement and identifies historical and contemporary examples of Buddhist poverty relief efforts

    Business Decisions In A Cooperative Environment

    Get PDF
    The trend for cooperative consolidation in the grain industry continues to be common throughout the United States.  In the state of Washington, for example, the total number of agribusiness cooperatives has decreased by nearly 40% over the past 3 decades.  Grain cooperatives in eastern Washington have diminished by 30% over this same period, and by 60% over the past 55 years (Monson, 2003).  The bulk of this reduction in numbers may be attributed to mergers and consolidations, but a few liquidations are also evident.  While many factors have contributed towards this long-standing trend, most would argue that a persistence of “economies of size” appears as a dominant force encouraging industry restructuring at almost every level.  The incentive and motivation to lower long-run average total costs by increasing size, capacity and volume is present for both types of grain agribusinesses (cooperatives and private (or publicly) owned businesses) while the implicit objective function for these different business forms is slightly different.  The primary objective for privately owned businesses is to maximize profit, subject to a constraint on technology which may be influenced by the private firm’s access to capital and management expertise.&nbsp

    A comprehensive radial velocity error budget for next generation Doppler spectrometers

    Full text link
    We describe a detailed radial velocity error budget for the NASA-NSF Extreme Precision Doppler Spectrometer instrument concept NEID (NN-explore Exoplanet Investigations with Doppler spectroscopy). Such an instrument performance budget is a necessity for both identifying the variety of noise sources currently limiting Doppler measurements, and estimating the achievable performance of next generation exoplanet hunting Doppler spectrometers. For these instruments, no single source of instrumental error is expected to set the overall measurement floor. Rather, the overall instrumental measurement precision is set by the contribution of many individual error sources. We use a combination of numerical simulations, educated estimates based on published materials, extrapolations of physical models, results from laboratory measurements of spectroscopic subsystems, and informed upper limits for a variety of error sources to identify likely sources of systematic error and construct our global instrument performance error budget. While natively focused on the performance of the NEID instrument, this modular performance budget is immediately adaptable to a number of current and future instruments. Such an approach is an important step in charting a path towards improving Doppler measurement precisions to the levels necessary for discovering Earth-like planets.Comment: 20 pages, 12 figures, published in Proc. of SPIE Astronomical Telescopes + Instrumentation 201

    The Carnegie Hubble Program: The Infrared Leavitt Law in IC 1613

    Get PDF
    We have observed the dwarf galaxy IC 1613, at multiple epochs in the mid-infrared using Spitzer and contemporaneously in the near-infrared using the new FourStar near-infrared camera on Magellan. We have constructed Cepheid period–luminosity relations in the J, H, K_s, [3.6] and [4.5] bands and have used the run of their apparent distance moduli as a function of wavelength to derive the line-of-sight reddening and distance to IC 1613. Using a nine-band fit, we find E(B − V) = 0.05 ± 0.01 mag and an extinction-corrected distance modulus of μ_0 = 24.29 ± 0.03_(statistical) ± 0.03_(systematic) mag. By comparing our multi-band and [3.6] distance moduli to results from the tip of the red giant branch and red clump distance indicators, we find that metallicity has no measurable effect on Cepheid distances at 3.6 μm in the metallicity range −1.0 ≤ [Fe/H] ≤ 0.2, hence derivations of the Hubble constant at this wavelength require no correction for metallicity

    Evidence for He I 10830 \AA~ absorption during the transit of a warm Neptune around the M-dwarf GJ 3470 with the Habitable-zone Planet Finder

    Full text link
    Understanding the dynamics and kinematics of out-flowing atmospheres of hot and warm exoplanets is crucial to understanding the origins and evolutionary history of the exoplanets near the evaporation desert. Recently, ground based measurements of the meta-stable Helium atom's resonant absorption at 10830 \AA~has become a powerful probe of the base environment which is driving the outflow of exoplanet atmospheres. We report evidence for the He I 10830 \AA~in absorption (equivalent width \sim 0.012±0.0020.012 \pm 0.002 \AA) in the exosphere of a warm Neptune orbiting the M-dwarf GJ 3470, during three transits using the Habitable Zone Planet Finder (HPF) near infrared spectrograph. This marks the first reported evidence for He I 10830 \AA\, atmospheric absorption for a planet orbiting an M-dwarf. Our detected absorption is broad and its blueshifted wing extends to -36 km/sec, the largest reported in the literature to date. We modelled the state of Helium atoms in the exosphere of GJ3470b based on assumptions on the UV and X-ray flux of GJ 3470, and found our measurement of flux-weighted column density of meta-stable state Helium (NHe32S=2.4×1010cm2)(N_{He^2_3S} = 2.4 \times 10^{10} \mathrm{cm^{-2}}), derived from our transit observations, to be consistent with model, within its uncertainties. The methodology developed here will be useful to study and constrain the atmospheric outflow models of other exoplanets like GJ 3470b which are near the edge of the evaporation desert.Comment: Accepted in Ap

    Solar Contamination in Extreme-precision Radial-velocity Measurements: Deleterious Effects and Prospects for Mitigation

    Get PDF
    Solar contamination, due to moonlight and atmospheric scattering of sunlight, can cause systematic errors in stellar radial velocity (RV) measurements that significantly detract from the ~10 cm s−1 sensitivity required for the detection and characterization of terrestrial exoplanets in or near habitable zones of Sun-like stars. The addition of low-level spectral contamination at variable effective velocity offsets introduces systematic noise when measuring velocities using classical mask-based or template-based cross-correlation techniques. Here we present simulations estimating the range of RV measurement error induced by uncorrected scattered sunlight contamination. We explore potential correction techniques, using both simultaneous spectrometer sky fibers and broadband imaging via coherent fiber imaging bundles, that could reliably reduce this source of error to below the photon-noise limit of typical stellar observations. We discuss the limitations of these simulations, the underlying assumptions, and mitigation mechanisms. We also present and discuss the components designed and built into the NEID (NN-EXPLORE Exoplanet Investigations with Doppler spectroscopy) precision RV instrument for the WIYN 3.5 m telescope, to serve as an ongoing resource for the community to explore and evaluate correction techniques. We emphasize that while "bright time" has been traditionally adequate for RV science, the goal of 10 cm s−1 precision on the most interesting exoplanetary systems may necessitate access to darker skies for these next-generation instruments

    Persistent starspot signals on M dwarfs: multi-wavelength Doppler observations with the Habitable-zone Planet Finder and Keck/HIRES

    Get PDF
    Young, rapidly-rotating M dwarfs exhibit prominent starspots, which create quasiperiodic signals in their photometric and Doppler spectroscopic measurements. The periodic Doppler signals can mimic radial velocity (RV) changes expected from orbiting exoplanets. Exoplanets can be distinguished from activity-induced false positives by the chromaticity and long-term incoherence of starspot signals, but these qualities are poorly constrained for fully-convective M stars. Coherent photometric starspot signals on M dwarfs may persist for hundreds of rotations, and the wavelength dependence of starspot RV signals may not be consistent between stars due to differences in their magnetic fields and active regions. We obtained precise multi-wavelength RVs of four rapidly-rotating M dwarfs (AD Leo, G 227-22, GJ 1245B, GJ 3959) using the near-infrared (NIR) Habitable-zone Planet Finder, and the optical Keck/HIRES spectrometer. Our RVs are complemented by photometry from Kepler, TESS, and the Las Cumbres Observatory (LCO) network of telescopes. We found that all four stars exhibit large spot-induced Doppler signals at their rotation periods, and investigated the longevity and optical-to-NIR chromaticity for these signals. The phase curves remain coherent much longer than is typical for Sunlike stars. Their chromaticity varies, and one star (GJ 3959) exhibits optical and NIR RV modulation consistent in both phase and amplitude. In general, though, we find that the NIR amplitudes are lower than their optical counterparts. We conclude that starspot modulation for rapidly-rotating M stars frequently remains coherent for hundreds of stellar rotations, and gives rise to Doppler signals that, due to this coherence, may be mistaken for exoplanets.Comment: Accepted for publication in the Astrophysical Journa

    A solar feed for NEID

    Get PDF
    NEID is a radial velocity (RV) instrument including an ultra-stabilized fiber-fed spectrograph, installed in 2019 at the 3.5m WIYN telescope at Kitt Peak National Observatory. Accompanying it is a solar feed system built to supply the spectrograph with disk-integrated sunlight. Observing the Sun “as a star” is essential for developing and validating mitigation strategies for RV variations due to stellar activity and instrument systematics, thus enabling more-effective detections of lower-mass exoplanets. In this paper, we will detail the design of the NEID solar feed system and showcase early results addressing NEID systematics and solar RV variability
    corecore