Torque control system

System stabilizes aximuth of gondolas which are carried by high-altitude balloons as platforms for tracking telescopes. When telescopes must be constantly aimed at specific targets, control system stabilizes gondola to within 5 arc-seconds

Asymmetries of Heavy Elements in the Young Supernova Remnant Cassiopeia A

Supernova remnants (SNRs) offer the means to study supernovae (SNe) long after the original explosion and can provide a unique insight into the mechanism that governs these energetic events. In this work, we examine the morphologies of X-ray emission from different elements found in the youngest known core-collapse (CC) SNR in the Milky Way, Cassiopeia A. The heaviest elements exhibit the highest levels of asymmetry, which we relate to the burning process that created the elements and their proximity to the center of explosion. Our findings support recent model predictions that the material closest to the source of explosion will reflect the asymmetries inherent to the SN mechanism. Additionally, we find that the heaviest elements are moving more directly opposed to the neutron star (NS) than the lighter elements. This result is consistent with NS kicks arising from ejecta asymmetries.Comment: 12 pages, 4 figures, 2 tables Updated to include an analysis of Emission Measure Maps (vs the, still-included, continuum-subtracted flux maps), used as another proxy for mass maps. The results have not changed; the emission measure maps also show increasing asymmetry with ejecta mass. (Now matches the version published in ApJ. Vol 889 Issue 2 (2020) 144

Application of numerical methods to planetary radiowave scattering

Existing numerical techniques for the solution of scattering problems were investigated to determine those which might be applicable to planetary surface studies, with the goal of improving the interpretation of radar data from Venus, Mars, the Moon, and icy satellites. The general characteristics of the models are described along with computational concerns. In particular, the Numerical Electrogmatics Code (NEC) developed at the Lawrence Livermore Laboratory is discussed. Though not developed for random rough surfaces, the NEC contains elements which may be generalized and which could be valuable in the study of scattering by planetary surfaces

Eye movement desensitisation and reprocessing for offence-related trauma in a mentally disordered sexual offender

Research demonstrates a high incidence of offence-related trauma in mentally disordered offenders convicted of violent and sexual offences. The adaptive information processing (AIP) model offers a theoretical framework for understanding the hypothesised relationship between offence-related trauma and reoffending. Evidence suggests that for a sub-population of offenders presenting with offence-related trauma: (1) therapy may retraumatise them, and (2) unresolved trauma severely blocks the positive benefits of talking therapies. Thus, it is postulated that traumatised violent and sexual offenders may be released into the community when they are still at risk of reoffending. A single case study is presented, which describes the application of eye movement desensitisation and reprocessing (EMDR) for a sexual offender presenting with offence-related trauma, whose offences occurred in the context of serious mental disorder. The identification of offence-related trauma and subsequent resolution of trauma symptomatology are discussed in regard to effective offender rehabilitation. Furthermore, the idiosyncratic nature of offence-related trauma and the application of the standard EMDR protocol for a single traumatic event are considered

Subcentimeter-size particle distribution functions in planetary rings from Voyager radio and photopolarimeter occultation data

Analysis of measurements of the scattered and direct components of Voyager 1 radio occultation signals at 3.5 and 13 cm wavelengths yield estimates of the distribution functions of supracentimeter-size particles and thickness of relatively broad regions in Saturn's rings. If mearurements of signal amplitude at a shorter wavelength are combined with the previously analyzed data, the shape of the distribution functions characterizing the smaller particles can be constrained. If size distributions of arbitrary form were considered, many solutions are found that are consistent with the three available observations of signal amplitude. The best-fit power law was calculated to the three observations at three wavelengths for several of the embedded Saturn ringlets. Mie scattering theory predicts that the measured phase of the radio occultation signal is highly sensitive to particles ranging from 0.1 to 1.0 wavelengths in size, thus additional constraints on the subcentimeter-size distribution functions for both the Saturn and Uranus rings can in principle be derived from radio phase measurements

Evaluation of cover crops in high tunnel vegetable rotation

Organic vegetable production within high tunnels allows for an extended growing season, crop protection, and environmental control. The USDA National Organic Program (NOP) standards mandate evidence that the soil has been maintained and improved over the course of production. Previous studies have indicated the potential of cover crops for reducing competitive vegetation, and improving soil quality, thus resulting in greater plant growth, nutrient uptake, and yield. However, there has been limited work in the confines of high tunnels as part of a tunnel-system rotation. Ten nitrogen-fixing and ten non-legume cover crops were established under a high tunnel and evaluated for their effects on the yield of ‘De Cicco’ broccoli (Brassica oleracea L. var. italica) and ‘Champion’ collards (Brassica oleracea L. var. acephala), aboveground biomass, and plant C and N contents. All treatments received recommended levels of appropriate certified organic fertilizers, water status was maintained, and vegetables received standard organic maintenance for insects and disease. The cover crops hairy indigo (Indigofera hirsuta L.), Catjang cowpea (Viana unguicalata L.), and Sunn hemp (Crotalaria juncea L.) consistently produced higher yields than Tifleaf III hybrid pearl millet (Pennisetum glaucum L.), Dairymaster brown midrib (BMR) hybrid grain sorghum (Sorghum spp.), and Wild Game Food sorghum (Sorghum bicolor L.). Nitrogenfixing legumes produced horticulturally significantly higher yields than the non-nitrogen-fixing grass species. This experiment demonstrated that not all cover crops are equal; they created variation in response. Cover crops provide a viable option for organic producers to maintain or improve soil quality over the course of production

The Age Evolution of the Radio Morphology of Supernova Remnants

Recent hydrodynamical models of supernova remnants (SNRs) demonstrate that their evolution depends heavily on the inhomogeneities of the surrounding medium. As SNRs expand, their morphologies are influenced by the non-uniform and turbulent structure of their environments, as reflected in their radio continuum emission. In this paper, we measure the asymmetries of 96 SNRs in radio continuum images from three surveys of the Galactic plane and compare these results to the SNRs' radii, which we use as a proxy for their age. We find that larger (older) SNRs are more elliptical/elongated and more mirror asymmetric than smaller (younger) SNRs, though the latter vary in their degrees of asymmetry. This result suggests that SNR shells become more asymmetric as they sweep up the interstellar medium (ISM), as predicted in hydrodynamical models of SNRs expanding in a multi-phase or turbulent ISM.Comment: 16 pages, 5 figures, accepted by ApJ; sample expanded from 22 to 96 source