HI and OH absorption in the lensing galaxy of MG J0414+0534

We report the detection of \HI 21-cm absorption in the $z=0.96$ early-type lensing galaxy towards MG J0414+0534 with the Green Bank Telescope. The absorption, with total $N_{\rm HI}=1.6 \times 10^{18} (T_{\rm s}/f) {\rm cm}^{-2}$, is resolved into two strong components, probably due to the two strongest lens components, which are separated by 0.4\arcsec. Unlike the other three lenses which have been detected in \HI, J0414+0534 does not exhibit strong OH absorption, giving a OH/\HI column density ratio of N_{\rm OH}/N_{\rm HI}\lapp10^{-6} (for $T_{\rm s}=100$ K, $T_{\rm x}=10$ K and $f_{\rm HI}=f_{\rm OH}=1$). This underabundance of molecular gas may indicate that the extreme optical--near-IR colour ($V-K=10.26$) along the line-of-sight is not due to the lens. We therefore suggest that despite the strong upper limits on molecular absorption at the quasar redshift, as traced by millimetre lines, the extinction occurs primarily in the quasar host galaxy.Comment: Accepted by MNRAS Letters, 5 (and a bit) pages, 5 figure

The role of proton precipitation in Jovian aurora: Theory and observation

It was proposed that the Jovian auroral emissions observed by Voyager spacecraft could be explained by energetic protons precipitating into the upper atmosphere of Jupiter. Such precipitation of energetic protons results in Doppler-shifted Lyman alpha emission that can be quantitatively analyzed to determine the energy flux and energy distribution of the incoming particle beam. Modeling of the expected emission from a reasonably chosen Voyager energetic proton spectrum can be used in conjunction with International Ultraviolet Explorer (IUE) observations, which show a relative lack of red-shifted Lyman alpha emission, to set upper limits on the amount of proton precipitation taking place in the Jovian aurora. Such calculations indicate that less than 10 percent of the ultraviolet auroral emissions at Jupiter can be explained by proton precipitation

Electrophysiological correlates of high-level perception during spatial navigation

We studied the electrophysiological basis of object recognition by recording scalp\ud electroencephalograms while participants played a virtual-reality taxi driver game.\ud Participants searched for passengers and stores during virtual navigation in simulated\ud towns. We compared oscillatory brain activity in response to store views that were targets or\ud nontargets (during store search) or neutral (during passenger search). Even though store\ud category was solely defined by task context (rather than by sensory cues), frontal ...\ud \u

GRB Energetics in the Swift Era

We examine the rest frame energetics of 76 gamma-ray bursts (GRBs) with known redshift that were detected by the Swift spacecraft and monitored by the satellite's X-ray Telescope (XRT). Using the bolometric fluence values estimated in Butler et al. 2007b and the last XRT observation for each event, we set a lower limit the their collimation corrected energy Eg and find that a 68% of our sample are at high enough redshift and/or low enough fluence to accommodate a jet break occurring beyond the last XRT observation and still be consistent with the pre-Swift Eg distribution for long GRBs. We find that relatively few of the X-ray light curves for the remaining events show evidence for late-time decay slopes that are consistent with that expected from post jet break emission. The breaks in the X-ray light curves that do exist tend to be shallower and occur earlier than the breaks previously observed in optical light curves, yielding a Eg distribution that is far lower than the pre-Swift distribution. If these early X-ray breaks are not due to jet effects, then a small but significant fraction of our sample have lower limits to their collimation corrected energy that place them well above the pre-Swift Eg distribution. Either scenario would necessitate a much wider post-Swift Eg distribution for long cosmological GRBs compared to the narrow standard energy deduced from pre-Swift observations. We note that almost all of the pre-Swift Eg estimates come from jet breaks detected in the optical whereas our sample is limited entirely to X-ray wavelengths, furthering the suggestion that the assumed achromaticity of jet breaks may not extend to high energies.Comment: 30 pages, 10 figures, Accepted to Ap

Mapping solar irradiance within Schrödinger Basin for future robotic sample return missions

The US National Research Council (NRC) identified eight scientific concepts and thirty-five prioritized investigations to be addressed with continued lunar exploration. These objectives are broadly consistent with those identified throughout the international community. the majority of these objectives require sample return from the Moon. Schrödinger basin has been highlighted as a particularly attractive location to find suitable samples

High velocity clouds in the Galactic All Sky Survey I. Catalogue

We present a catalogue of high-velocity clouds (HVCs) from the Galactic All Sky Survey (GASS) of southern-sky neutral hydrogen, which has 57 mK sensitivity and 1 km/s velocity resolution and was obtained with the Parkes Telescope. Our catalogue has been derived from the stray-radiation corrected second release of GASS. We describe the data and our method of identifying HVCs and analyse the overall properties of the GASS population. We catalogue a total of 1693 HVCs at declinations < 0 deg, including 1111 positive velocity HVCs and 582 negative velocity HVCs. Our catalogue also includes 295 anomalous velocity clouds (AVCs). The cloud line-widths of our HVC population have a median FWHM of ~19 km/s, which is lower than found in previous surveys. The completeness of our catalogue is above 95% based on comparison with the HIPASS catalogue of HVCs, upon which we improve with an order of magnitude in spectral resolution. We find 758 new HVCs and AVCs with no HIPASS counterpart. The GASS catalogue will shed an unprecedented light on the distribution and kinematic structure of southern-sky HVCs, as well as delve further into the cloud populations that make up the anomalous velocity gas of the Milky Way.Comment: 21 pages, 14 figures, accepted for publication in ApJ

Multi-scale analysis and validation of the Envisat MERIS Terrestrial Chlorophyll Index (MTCI) in woodland

Satellite remote sensing can be used to estimate and monitor the chlorophyll content of vegetation canopies which are a key and dynamic component of global terrestrial ecosystems. The red-edge algorithm can be used to estimate chlorophyll content from remotely sensed data but is unsuitable for use with most satellite sensor imagery. To overcome this problem, the new Envisat MERIS Terrestrial Chlorophyll index (MTCI) has been developed. It is the only operational satellite chlorophyll index and MTCI data are available as a Level 2 product from the European Space Agency. However, there is a need to ‘validate’ the MTCI over a wide range of environmental conditions. This paper reports on research that attempts to validate the MTCI using Compact Airborne Spectrographic Imager (CASI) imagery and ground data of chlorophyll content. The study site was predominantly woodland in the south of England (New Forest National Park) and had a wide range of chlorophyll contents. A transfer function derived from CASI data was used to produce a reference map of chlorophyll content, when aggregated it was compared to MERIS MTCI data and used to derive the MTCI – chlorophyll content relationship (R squared = 0.56)

The Probability Distribution of Binary Pulsar Coalescence Rate Estimates. II. Neutron Star-White Dwarf Binaries

We consider the statistics of pulsar binaries with white dwarf companions (NS-WD). Using the statistical analysis method developed by Kim et al. (2003) we calculate the Galactic coalescence rate of NS-WD binaries due to gravitational-wave emission. We find that the most likely values for the total Galactic coalescence rate (R_tot) of NS-WD binaries lie in the range 0.2--10 per Myr depending on different assumed pulsar population models. For our reference model, we obtain R_tot=4.11_(-2.56)^(+5.25) per Myr at a 68% statistical confidence level. These rate estimates are not corrected for pulsar beaming and as such they are found to be about a factor of 20 smaller than the Galactic coalescence rate estimates for double neutron star systems. Based on our rate estimates, we calculate the gravitational-wave background due to coalescing NS-WD binaries out to extragalactic distances within the frequency band of the Laser Interferometer Space Antenna. We find the contribution from NS-WD binaries to the gravitational-wave background to be negligible.Comment: 20 pages, 2 figures, 2 tables, Accepted for publication in Ap

Patient Perspectives on Medication Assisted Therapy in Vermont

Introduction. Medication-Assisted Therapy (MAT) for opioid addiction has dramatically increased in Vermont, supported by a novel statewide system that integrates specialty treatment centers ( Hubs ) with primary care office-based opioid therapy ( Spokes ). In 2010, Vermont had the highest per capita buprenorphine use in the US. Previous studies of patient perspectives of MAT have identified social barriers, rigid program rules, and concerns about withdrawal and relapse as common causes of treatment failure. Our goal was to elicit patient perspectives on barriers and enablers of successful MAT to further inform system refinement. Methods. An interview guide was developed based on previous literature as well as discussions with program leadership, staff and clinicians, and community stakeholders. Responses were organized using thematic content analysis with consensus across seven interviewers and two analysts. The interviews were conducted with 44 patients enrolled in MAT at two Hub sites in Burlington, VT in October 2016. Results. The median age of subjects was 34 years, 34% were employed at least part-time, and 72% were female. Half reported a mental health condition and 20% reported chronic pain. Barriers included transportation (25%), lack of stable housing, and stigma (41%). Enablers included feeling supported (82% felt well-supported; 52% felt supported by healthcare professionals). Subjects expressed high confidence in the treatment system and high self-efficacy for sobriety. Conclusions. Patients in MAT have complex medical, mental health, social, personal, and work lives. A comprehensive system that addresses this wide range of domains is critical to achieving optimal outcomes.https://scholarworks.uvm.edu/comphp_gallery/1245/thumbnail.jp

Information content of ozone retrieval algorithms

The algorithms are characterized that were used for production processing by the major suppliers of ozone data to show quantitatively: how the retrieved profile is related to the actual profile (This characterizes the altitude range and vertical resolution of the data); the nature of systematic errors in the retrieved profiles, including their vertical structure and relation to uncertain instrumental parameters; how trends in the real ozone are reflected in trends in the retrieved ozone profile; and how trends in other quantities (both instrumental and atmospheric) might appear as trends in the ozone profile. No serious deficiencies were found in the algorithms used in generating the major available ozone data sets. As the measurements are all indirect in someway, and the retrieved profiles have different characteristics, data from different instruments are not directly comparable