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Nearly 4 % of the world’s forests are plantations, established to provide a variety of ecosystem services, principally timber and other wood products. In addition to such services, plantation forests provide direct and indirect benefits to biodiversity via the provision of forest habitat for a wide range of species, and by reducing negative impacts on(More)
The University of Maryland Electron Ring (UMER) group is currently exploring the physics of space-charge dominated beams. Seventeen Beam Position Monitors (BPMs) will be used to determine the beam centroid for steering correction purposes to within 0.5 mm. Since the pulse length is relatively long (100 ns), the BPMs can also be used for temporal beam(More)
In this paper we calculate the particle creation as seen by a stationary observer in an anisotropic universe. By using an observer and geometry dependent time to quantise a massive scalar field we show that a discrete energy spectrum shift occurs. The length scale associated with the geometry provides the energy scale by which the spectrum is shifted. The(More)
The amount and nature of dark energy (DE) can be tightly constrained by measuring the spatial correlation features and evolution of a sample of ∼ 100, 000 galaxy clusters over the redshift range 0 < z < ∼ 1.5. Such an X-ray survey will discover all collapsed structures with mass above 3.5 × 10 14 h −1 M ⊙ at redshifts z < 2 (i.e. the full range where such(More)
Initial experimental results are presented for measurements of the emittance of an electron beam in the University of Maryland Electron Ring (UMER). Two independent sets of slit-collector systems are used to measure the emittance in the vertical and horizontal directions respectively. Results are then compared to the time integrated emittance measurements(More)
Alignment of experimental components is critical to operation of The University of Maryland Electron Ring (UMER). Procedures and equipment used to align components of the electron ring are presented. The compact nature of UMER (ring diameter ≈ 4 m) presents unique challenges and advantages associated with the placement of vacuum components, confinement and(More)
In this paper we calculate the massive particle creation as seen by a stationary observer in a 1 + 1 dimensional spacetime compact in space. The Bogolubov transformation relating the annihilation and creation operators between two spacelike surfaces is calculated. The particle creation, as observed by a stationary observer who moves from the first spacelike(More)
The elastic electroproduction of mesons is studied at HERA with the H1 detector for photon virtualities ½ É ¾ ½½ Î ¾ and hadronic centre of mass energies ¼ Ï ½¿¼ GeV. The É ¾ and Ø dependences of the cross section are extracted (Ø being the square of the four-momentum transfer to the target proton). When plotted as function of (É ¾ + Å ¾ Î) and scaled by(More)
To investigate the variation in post-cure palatal discrepancy of dentures, 20 complete maxillary replica dentures were prepared on models with high and low palates and processed by conventional compression moulding and injection moulding. Measurements were made by travelling microscope of the sagittal midline discrepancies between palate and model on three(More)