An Integral Field Study of Abundance Gradients in Nearby LIRGs

We present for the first time metallicity maps generated using data from the Wide Field Spectrograph (WiFeS) on the ANU 2.3m of 9 Luminous Infrared Galaxies (LIRGs) and discuss the abundance gradients and distribution of metals in these systems. We have carried out optical integral field spectroscopy (IFS) of several several LIRGs in various merger phases to investigate the merger process. In a major merger of two spiral galaxies with preexisting disk abundance gradients, the changing distribution of metals can be used as a tracer of gas flows in the merging system as low metallicity gas is transported from the outskirts of each galaxy to their nuclei. We employ this fact to probe merger properties by using the emission lines in our IFS data to calculate the gas-phase metallicity in each system. We create abundance maps and subsequently derive a metallicity gradient from each map. We compare our measured gradients to merger stage as well as several possible tracers of merger progress and observed nuclear abundances. We discuss our work in the context of previous abundance gradient observations and compare our results to new galaxy merger models which trace metallicity gradient. Our results agree with the observed flattening of metallicity gradients as a merger progresses. We compare our results with new theoretical predictions that include chemical enrichment. Our data show remarkable agreement with these simulations.Comment: Accepted for publication in ApJ. 26 pages, 18 figure

Austere Location Wind Turbine Energy System Analysis

One promising technology to combat an energy shortage in austere locations is wind energy. In combination with battery storage and generator backup, we explore the feasibility of using a hybrid energy system to reduce the volume of diesel fuel required. Modeling the energy demands in austere locations will enable missions in remote settings to optimize their energy costs, increased their energy resiliency and assure their supply. For a modeled time-series energy requirement that varied between 2.4 MW and 5.1 MW, the optimal wind system size was 9.9 MW of installed wind power paired with a 741 kWh battery. Assuming an elevated price of fuel, the cost of operating the base with only fuel was greater than $55 million dollars. The total component and operational cost of the optimized wind, generator and battery system was cost-effective within one year and totaled$48 million dollars

36% Reduction in Fuel Resupply Using a Hybrid Generator & Battery System for an Austere Location

The DOD energy policy is to increase energy security resiliency, and mitigate costs in the use and management of energy[1] Forward operating bases (FOBs) are remote, austere base camps that support an operationally defined mission with a limited or no ability to draw from an energy grid and have historically relied on diesel-powered generators for the primary production of energy.[2] Generators are sized to meet a theoretical peak demand, but steady state loads are far below this peak, resulting in under-loaded generators.[3] Under-loaded diesel generators decrease efficiency and increase the need for maintenance, affecting the lifespan of the systems[4,5] This article analyzes the coupling of current power generation technology with energy storage. The addition of optimized energy storage to current diesel generators reduces fuel consumption by 36 percent and reduces energy system costs by 24 percent. Decreased fuel requirements at outlying FOBs equates to fewer resupply convoys, reducing operational fuel use, time spent outside the wire by service members and associated combat casualties. Abstract © Marine Corps Association

Dimethyl sulphide in some Australian red wines

DMS levels in Cabernet Sauvignon wine from the Coonawarra area of southeast South Australia were shown to vary from 42 to 910 μg l-1. Results indicate that the levels are not dependent on age but rather vary from vintage to vintage. This study does not discount the development of DMS with bottle age as it is an 'historical' survey but suggests that the levels of DMS are vintage related and may depend on viticultural practices and vinification techniques. The odour threshold for DMS in Cabernet Sauvignon was 0.07 μl l-1 (60μg l -1)

Photovoltaic System Optimization for an Austere Location Using Time Series Data

In this work we test experimental photovoltaic, storage and generator technologies and investigate their potential to meet austere location energy needs. After defining the energy requirements and insolation of a 1,100-person base, we develop a microgrid model and simulation. Cost optimizations were then performed using hourly time-series data to explore the cost and performance trade-space of a PV-battery-generator system. The work highlights the cost of resiliency and the dependencies of optimum system component sizes on duration and the fully burdened cost of fuel

Ex. 277-US-415

The 2004 annual report on riverine movements of adult Lost River, shortnose, and Klamath largescale suckers in the Williamson and Sprague rivers, Orego

Ex. 277-US-415

The 2004 annual report on riverine movements of adult Lost River, shortnose, and Klamath largescale suckers in the Williamson and Sprague rivers, Orego

Hot Gaseous Coronae around Spiral Galaxies: Probing the Illustris Simulation

The presence of hot gaseous coronae around present-day massive spiral galaxies is a fundamental prediction of galaxy formation models. However, our observational knowledge remains scarce, since to date only four gaseous coronae were detected around spirals with massive stellar bodies ($\gtrsim2\times10^{11} \ \rm{M_{\odot}}$). To explore the hot coronae around lower mass spiral galaxies, we utilized Chandra X-ray observations of a sample of eight normal spiral galaxies with stellar masses of $(0.7-2.0)\times10^{11} \ \rm{M_{\odot}}$. Although statistically significant diffuse X-ray emission is not detected beyond the optical radii ($\sim20$ kpc) of the galaxies, we derive $3\sigma$ limits on the characteristics of the coronae. These limits, complemented with previous detections of NGC 1961 and NGC 6753, are used to probe the Illustris Simulation. The observed $3\sigma$ upper limits on the X-ray luminosities and gas masses exceed or are at the upper end of the model predictions. For NGC 1961 and NGC 6753 the observed gas temperatures, metal abundances, and electron density profiles broadly agree with those predicted by Illustris. These results hint that the physics modules of Illustris are broadly consistent with the observed properties of hot coronae around spiral galaxies. However, a shortcoming of Illustris is that massive black holes, mostly residing in giant ellipticals, give rise to powerful radio-mode AGN feedback, which results in under luminous coronae for ellipticals.Comment: 12 pages, 6 figures, accepted for publication in Ap

Chemical pre-processing of cluster galaxies over the past 10 billion years in the IllustrisTNG simulations

We use the IllustrisTNG simulations to investigate the evolution of the mass-metallicity relation (MZR) for star-forming cluster galaxies as a function of the formation history of their cluster host. The simulations predict an enhancement in the gas-phase metallicities of star-forming cluster galaxies (10^9< M_star<10^10 M_sun) at z<1.0 in comparisons to field galaxies. This is qualitatively consistent with observations. We find that the metallicity enhancement of cluster galaxies appears prior to their infall into the central cluster potential, indicating for the first time a systematic "chemical pre-processing" signature for {\it infalling} cluster galaxies. Namely, galaxies which will fall into a cluster by z=0 show a ~0.05 dex enhancement in the MZR compared to field galaxies at z<0.5. Based on the inflow rate of gas into cluster galaxies and its metallicity, we identify that the accretion of pre-enriched gas is the key driver of the chemical evolution of such galaxies, particularly in the stellar mass range (10^9< M_star<10^10 M_sun). We see signatures of an environmental dependence of the ambient/inflowing gas metallicity which extends well outside the nominal virial radius of clusters. Our results motivate future observations looking for pre-enrichment signatures in dense environments.Comment: 5 pages, 4 figures, accepted for publication in MNRAS Letter