Absolute rigidity spectrum of protons and helium nuclei above 10 GV/c

Proton and helium nuclei differential spectra were gathered with a balloon borne magnet spectrometer. The data were fitted to the assumption that the differential flux can be represented by a power law in rigidity. In the rigidity range 10 to 25 GV/c the spectral indices were found to be -(2.74 plus or minus 0.04) for protons and -(2.71 plus or minus 0.05) for helium nuclei. A brief discussion is given by systematic errors

Symmetrically H-Bridged Dimer of 2-Carboxylatobenzenediazonium. The 1:1 Complex between 2-Carboxybenzenediazonium Chloride and Benzenediazonium-2-carboxylate

The two zwitterions in the H-bridged dimer of 2-carboxylatobenzenediazonim (1) are linked by a crystallographically symmetric O⋯Hctdot;O hydrogen bond with an O⋯O distance of 2.436 (3) Å. Comparison of the (1) with the other benzenediazonium salts shows that the phenyl ring distortions in (1) are determined primarily by the diazonium substituent with only modest additional effects by the carboxylato group. Intramolecular neighboring goup interactions between the N2 group and the orthoCOO(H) group are indicated and are discussed. The terminal N atom of the diazonium group is bent away from the neighboring carboxylato group. The N2 and the carboxylato group are on the opposite sides of the best plane of the aromatic ring. Importantly, the carboxylato group is not fully conjugated with the aromatic ring but instead is rotated 6.5 (2)° around the C-CO2 axis in a fashion that suggest minimization of intramolecular repulsion between Nα and the proximate O atom and optimization of the inter-molecular hydrogen bonding

The Effect of Various Pasture-based Systems of Milk Production on Animal Performance in the Northeast Region of Ireland

End of Project ReportThe potential of Irish soils to grow grass throughout the year and success in utilizing grass are key factors affecting output and profitability of dairy production systems (Shalloo et al., 2004). In the Northeast region of Ireland, the potential grazing season is shortened due to impeded land drainage, topography, high rainfall and northerly aspect. The main focus of the Ballyhaise research programme is to develop more sustainable production systems suitable to the limitations of the region with a specific focus on grass growth and utilization. Progress in these technologies will improve the competitiveness of dairying in the Northeast region. We are also now faced with a new economic environment with market forecasts predicting a steady decline in dairy product prices for Irish dairy farmers while input prices continue to increase. It has been shown from previous studies that dairy farmers need to expand and/or increase the efficiency of their dairy operation to maintain their real farm incomes over the coming years (Breen and Hennessey, 2003). It is likely that land purchase price will continue to be high in future years. Firstly, dairy farmers can continue at their current level of production and efficiency, and suffer a decline in farm profit as milk price falls. It is likely that greater amounts of milk quota will become available in the coming years; therefore many dairy farmers will have the option to increase production. Expansion opportunities will be limited by the key constraints such as labour supply and cost, capital cost, milk quota availability and price and availability of land around the milking parlour. Labour efficient work practices will have to be adopted on farms to allow one operator to manage a greater number of cows. The objective of this experiment was to examine the effect of two divergent pasture-based systems of milk production on animal performance over a two-year period and to subsequently describe the optimum system for dairy farmers in the Northeast region both now and into the future

Observation of cosmic ray positrons from 5 to 25 GeV

The positron data gathered in conjunction with electron data published elsewhere is reported. The basic recognition scheme was to look for low mass positive particles that cause a cascade in a 7 radiation length shower counter. The mass criteria is imposed by selecting particles that were accompanied by Cherenkov light but whose rigidity was below the proton Cherenkov threshold. Thus the proton Cherenkov threshold represents an upper limit to the range of the experiment

Three Corner Sat Constellation - New Mexico State University: Communications, LEO Telecommunications Services, Intersatellite Communications, and Ground Stations and Network

The Three Corner Satellite Constellation is part of the AFOSRlDARP A University Nanosatellite program. This project is a joint effort among Arizona State University (ASU), University of Colorado at Boulder (CU), and New Mexico State University (NMSU). The constellation will consist of three identical nanosatellites, that will demonstrate stereo imaging, innovative command and data handling, and formation flying with RF communications and a possibility of cellular phone communications through LEO telecommunications satellites. To achieve mission objectives, the satellites in the constellation and the ground communications network will need to be designed as a cooperative communications and control network that will allow the satellites in the constellation to form a virtual formation. In this paper, we will present the necessary communications and control architecture for the space segment and the ground segment to form this virtual formation that are NMSU\u27s responsibility in the program. Companion papers describe the respective areas of responsibility of the other partners: ASU -Project Management; Electrical Power System; Structures, Mechanisms, Thermal, and Radiation; Attitude/Orbit Determination and Control; Micropropulsion experiment; and • Integration; CU -- Command & Data Handling, Distributed Operations, Stereoscopic Imaging, Science Operations, and Spacecraft Operations

The Gamma Ray Burst section of the White Paper on the Status and Future of Very High Energy Gamma Ray Astronomy: A Brief Preliminary Report

Original paper can be found at: http://proceedings.aip.org/proceedings/ Copyright American Institute of Physics DOI: 10.1063/1.2943545otherPeer reviewe

Mrk 421, Mrk 501, and 1ES 1426+428 at 100 GeV with the CELESTE Cherenkov Telescope

We have measured the gamma-ray fluxes of the blazars Mrk 421 and Mrk 501 in the energy range between 50 and 350 GeV (1.2 to 8.3 x 10^25 Hz). The detector, called CELESTE, used first 40, then 53 heliostats of the former solar facility "Themis" in the French Pyrenees to collect Cherenkov light generated in atmospheric particle cascades. The signal from Mrk 421 is often strong. We compare its flux with previously published multi-wavelength studies and infer that we are straddling the high energy peak of the spectral energy distribution. The signal from Mrk 501 in 2000 was weak (3.4 sigma). We obtain an upper limit on the flux from 1ES 1426+428 of less than half that of the Crab flux near 100 GeV. The data analysis and understanding of systematic biases have improved compared to previous work, increasing the detector's sensitivity.Comment: 15 pages, 14 figures, accepted to A&A (July 2006) August 19 -- corrected error in author lis

Unravelling the controls on the molybdenum isotope ratios of river waters

The molybdenum (Mo) isotope ratios (δ98/95Mo) of river waters control the δ98/95Mo values of seawater and impact on the use of Mo isotope ratios as a proxy of past redox conditions. The δ98/95Mo values of river waters vary by more than 2 ‰, yet the relative roles of lithology versus fractionation during weathering remain contested. Here, we combine measurements from river waters (δ98/95Modiss), river bed materials (δ98/95MoBM) and soils from locations with contrasting lithology. The δ98/95Mo values of river bed materials (δ98/95MoBM), set by rock type, vary by ~1 ‰ between rivers in New Zealand, the Mackenzie Basin, and Iceland. However, the difference between dissolved and solid phase Mo isotopes (Δ98/95Modiss-BM) varies from +0.3 ‰ to +1.0 ‰. We estimate Mo removal from solution using the mobile trace element rhenium and find that it correlates with Δ98/95Modiss-BM across the sample set. The adsorption of Mo to Fe-Mn-(oxyhydr)oxides can explain the observed fractionation. Together, the amount of Mo released through dissolution and taken up by (oxyhydr)oxide formation on land may cause changes in the δ98/95Mo values of rivers, driving long term changes in the Mo isotope ratios of seawater