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Marine protected areas (MPAs) are increasingly being established to protect and rebuild coastal and marine ecosystems. However, while the high seas are increasingly subject to exploitation, globally few MPAs exist in areas beyond national jurisdiction. In 2010 a substantial step forward was made in the protection of high seas ecosystems with 286,200 km 2 of the North-East Atlantic established as six MPAs. Here a summary is presented of how the world's first network of high seas marine protected areas was created under the OSPAR Convention, the main challenges and a series of key lessons learned, aiming to highlight approaches that also may be effective for similar efforts in the future. It is concluded that the designation of these six MPAs is just the start of the process and to achieve ecological coherence and representativity in the North-East Atlantic, the network will have to be complemented over time by additional MPA sites.

A VLSI implementation of an artificial neural network using a single n-channel MOS (metal-oxide semiconductor) transistor per synapse is investigated. The simplicity of the design is achieved by using pulse width modulation to represent neural activity and by using a novel technique to manipulate negative weights. A simple multilayer perceptron (MLP) network was simulated using the SPICE circuit simulator and the performance of a hardware realization of the same MLP network was measured. Simulations and measurements are shown to agree well. >

A pulsed power supply is being designed to deliver 5 MJ at 1 MA at 1 shot per second to a railgun. The supply stores energy at low current in the primary of a hydrogen-cooled transformer. A switch opens the primary circuit to transfer energy to the secondary, stepping the current up to 1 MA. The relationship between the transformer and switch is being studied to determine how the total power supply mass can be minimized. Vacuum interrupters and gate-turn-off (GTO) thyristors are used in the switch. Switch mass dominates the system, accounting for 85% of the total mass. The switch must absorb the uncoupled energy of the transformer. Low transformer coupling requires large capacitors. Even with high coupling, capacitors account for 75 to 85% of the switch mass. If transformer coupling increases, the uncoupled energy decreases, resulting in lower capacitor mass. At high transformer coupling, switch mass also depends on the turns ratio of the transformer. At lower turns ratio, a lower voltage is placed across the switch capacitors. Lighter capacitors can be used, reducing system mass. The combined transformer and switch (system) mass is minimized when transformer coupling is 0.97 to 0.99 and the turns ratio is as low as possible. >

Two possible switches topologies used to switch the primary of an energy storage transformer are compared. A series-connected semiconductor/vacuum interrupter switch and an all-solid-state switch are sized for a 5 MJ energy storage transformer. Gate-turn-off (GTO) thyristors are used as the semiconductor switches. Total mass estimates, operating characteristics, and applicability to a space-based pulsed power system are discussed. Both designs store the commutation energy in capacitors. The communication energy is then dissipated in resistors after switching has occurred. The capacitor mass is shown to dominate the total switch mass. Therefore, the mass of both switches is approximately equal. The advantages of the all-solid-state switch include high reliability, no moving parts, proven design, and a high probability of future mass reduction with new semiconductor device developments. The all-solid-state switch has a higher on-state power dissipation than the vacuum interpreter switch. it is suggested that the advantages of the all-solid-state switch outweigh the disadvantages of the higher power dissipation. >

An 8 GeV superconducting linear accelerator (SCL) has been proposed [1] as a single stage H- injector into the Main Injector (MI) synchrotron . This would be the highest energy H- multi-turn injection system in the world. The conceptual design of an injection system has been further refined by addressing transverse phase space painting issues, chicane dipole fields and foil location, foil temperature issues, and initial longitudinal phase space painting simulations. We present the current state of design.

An 8 GeV superconducting linear accelerator (SCL) has been proposed as a single stage H- injector into the Main Injector (MI) synchrotron[1]. This would be the highest energy H- multi-turn injection system in the world. An injection absorber is required to absorb a few percent o the incoming beam on a regular pulse by pulse basis. The requirements and conceptual design of an internal absorber, capable of steady state 6.5 kW is discussed.

During the design of the Fermilab Main Injector synchrotron it was recognized that the aperture was limited at the beam transfer and extraction points by the combination of the Lambertson magnets and the reused Main Ring quadrupoles located between the Lambertsons. Increased intensity demands on the Main Injector from antiproton production for the collider program, slow spill to the meson fixed target program, and high intensity beam to the high energy neutrino program have led us to replace the aperture-limiting quadrupoles with newly built magnets that have the same physical length but a larger aperture. The magnets run on the main quadrupole bus, and must therefore have the same excitation profile as the magnets they replaced. We present here the design of the magnets, their magnetic performance, and the accelerator performance.

Upon the termination of the Fermilab Collider program, the current Recycler anti-proton storage ring will be converted to a proton pre-injector for the Main Injector synchrotron. This is scheduled to increase the beam power for the 120 GeV Neutrino program to upwards of 700 KW. Due to momentum aperture requirements, a Recycler to Main Injector transport line will be constructed wholly within a horizontal dispersion free region in the 30 straight section. The concept design will be presented in this paper.

Upon the termination of the Fermilab Collider program, the current Recycler anti-proton storage ring (RR) will be converted to a proton pre-injector for the Main Injector (MI) synchrotron. This is scheduled to increase the beam power for the 120 GeV Neutrino program to upwards of 700 KW. A transport line that can provide direct injection from the Booster to the Recycler while preserving direct injection from the Booster into the Main Injector and the 8 GeV Booster Neutrino program will be discussed, and its concept design will be presented.

Results of modeling with the 3-D STRUCT and MARS 15 codes of beam loss localization and related radiation effects are presented for the slipstacking injection to the Fermilab Main Injector. Simulations of proton beam loss are done using multi-turn tracking with realistic accelerator apertures, nonlinear fields in the accelerator magnets and time function of the RF manipulations to explain the results of beam loss measurements. The collimation system consists of one primary and four secondary collimators. It intercepts a beam power of 1.6 kW at a scraping rate of 5% of 5.5E+13 ppp, with a beam loss rate in the ring outside the collimation region of 1 W/m or less. Based on thorough energy deposition and radiation modeling, a corresponding collimator design was developed that satisfies all the radiation and engineering constraints.

To maximize the tune space due to momentum spread, an operating point close to the coupling resonance line is desirable. This requires a knowledge of all the coupling sources in the Recycler and a correction system capable of global decoupling to the desired level. We report on the efforts to identify major sources of coupling and verification of the integrity of the powered skew quad circuits used for global decoupling

In the commissioning of the Fermilab Recycler ring the need for higher order corrector magnets in the regions near beam transfer lines was discovered. Three types of permanent magnet skew quadrupoles, and two types of permanent magnet sextupoles were designed and built. This paper describes the need for these magnets, the design, assembly, and magnetic measurements.

The Recycler Ring, an 8 GeV antiproton accumulator, is being commissioned at Fermilab. Antiproton transfers in and out of the Recycler Ring take place through two transfer lines connecting the Recycler to the Main Injector. Transfer line layout and operation of beam transfers will be described. Particular attention has been paid to injection mismatch effects, in order to limit emittance growth during transfers. A considerable improvement has been achieved by removing vacuum windows, previously present in both transfer lines.

Round-trip beam transfers between the Fermilab Main Injector and Recycler (antiproton accumulator) have been plagued by an emittance dilution of about a factor of 2 with corresponding beam loss. The source of the large dilution was traced to two Ti vacuum windows, one installed in each of the two transfer lines that connect the machines for beam injection/extraction. The dilution can be accounted for by calculating the increase in beam divergence due to multiple scattering in the windows followed by an amplitude mismatch that serves to further enhance the instantaneous dilution immediately downstream of the window. This work presents the analytical basis for the phase-space, or emittance, dilution due to the window, the subsequent optics mismatch, and then presents an analysis of beamline measurements that evidences the effect and validates the analytical argument. The data showed a strong skew quadrupole component in the transfer line optics that initially complicated the analysis, but was effectively eliminated in some of the data samples acquired under specific beam conditions.

We describe methods used to measure and control tunes in the Fermilab Main Injector (FMI). Emphasis is given to software implementation of the operator interface, to the front-end embedded computer system, and handling of hysteresis of main dipole and quadrupole magnets. Techniques are developed to permit control of tune of the Main Injector through several acceleration cycles: from 8.9 GeV/c to 120 GeV/c, from 8.9 GeV/c to 150 GeV/c, and from 150 GeV/c to 8.9 GeV/c. Systems which automate the complex interactions between tune measurement and the variety of ramping options are described. Some results of tune measurements and their comparison with the design model are presented.

Chromaticity control in the Fermilab Main Injector will be important both in accelerating protons and antiprotons from 8 GeV to 150 GeV (or 120 GeV) and in decelerating recycled 150 GeV antiprotons to 8 GeV for storage in the Recycler Ring. The Main Injector has two families of sextupoles to control the chromaticity. In addition to the natural chromaticity, they must correct for sextupole fields from ramp-rate-dependent eddy currents in the dipole beam pipes and current-dependent sextupole fields in the dipole magnets. The horizontal sextupole family is required to operate in a bipolar mode below the transition energy of 20 GeV. We describe methods used to control chromaticities in the Fermilab Main Injector. Emphasis is given to the software implementation of the operator interface to the front-end ramp controllers. Results of chromaticity measurements and their comparison with the design model will be presented.

Results of the continuing analysis of the nonlinear dynamics experiment, E778, are presented. Sixteen special sextupoles introduced nonlinearities in the Tevatron. Smear, which is one of the parameters used to quantify the degree of nonlinearity, was extracted from the data and compared with calculation. Injection efficiency in the presence of nonlinearities was studied. Measurements of the dynamic aperture were performed. The final results in one degree of freedom of the smear, the injection efficiency, and the dynamic aperture are presented. Particles captured on nonlinear resonance islands were directly observed and measurements were taken. The capture efficiency was extracted from the data and compared with prediction. The influence of tune modulation on the stability of these islands was investigated. Plans for future measurements are discussed. >

Results of a study made to evaluate the coil-winding aperture needed for the final booster in the injector chain for the SSC (Superconducting Super Collider) are presented. Lattice designs based on 5-cm and 7-cm dipole apertures are evaluated by looking at the long-term dynamic aperture, at injection and the good-field aperture requirement for resonant extraction of high-energy test beams. The 5-cm dipole is found to be marginal, while the 7-cm dipole satisfies field quality criteria for both injection and extraction. >

Tests have been performed at Fermilab on 1.5-m magnetic length model SSC (Superconducting Super Collider) dipoles using both bipolar and unipolar ramp cycles. Hysteresis energy loss due to superconductor and iron magnetization and eddy currents is measured and compared as a function of various ramp parameters. Additionally, magnetic field measurements have been performed for both unipolar and bipolar ramp cycles. Measurements such as these will be used to estimate the heat load during collider injection for the SCC High Energy Booster dipoles. >

The upgraded Tevatron collider has two new matched low beta insertions and operates with electrostatic separators to have different orbits for the proton and pbar beams. A general-purpose application program has been developed which allows the operator to control approximately 200 function generators and associated timers to commission, tune, and operate the machine. The program and relevant aspects of the Fermilab controls environment are discussed. >

This paper describes the design of a compact electron synchrotron light source for producing X-rays for medical imaging, protein crystallography, nano-machining and other uses up to 35 keV. The source will provide synchrotron light from six 6.9 tesla superconducting 60/spl deg/ bending magnet stations. In addition the ring, contains conventional quadrupoles and sextupoles. The light source has a circumference of 26 meters, which permits it to be located in a variety of industrial and medical facilities.

The Recycler Ring Gradient Magnets were designed with end shims which correct the field shape (harmonic components up to 10-pole). A standard correction was employed at one end to correct the average properties. A variable correction was used at the other end to correct individual magnet variations during the fabrication process. An initial Recycler operation revealed that the quadrupole fields did not produce the desired tune. In part, this was due to the sextupole of the end-shim interacting with the curved orbit through the straight magnet. The standard end-shim was replaced on all regular cell gradient magnets. Details of these end corrections and the resulting successful modification of the lattice are described.

The design of the newly installed medium-/spl beta/ insert of the Fermilab Recycler Ring is presented. The design philosophy is outlined. The stringent optical and physical constraints, as well as their influence on the design, are discussed. The impact of the medium-/spl beta/ insert on the Recycler Ring is shown. The engineering design and installation of the new insert is presented.

Slow resonant extraction from the Fermilab Main Injector through the extraction channel was achieved in February 2000, with a spill length of 0.3 sec. Beam losses were small. Excellent wire chamber profiles were obtained and analyzed. The duty factor was not very good and needs to be improved.

A study undertaken to determine the potential improvement in efficiency of energy-storage transfers is described. Energy stores of 5 MJ and 1 MA were sized and studied. The performance of transformers made from conductor-grade aluminium was compared with that of transformers made from hyperconductor. It was found that the hyperconductor results in considerable improvement in performance. It is believed that hyperconducting aluminium can be used to build energy storage inductors and transformers that store at least 15 kJ/kg. This specific energy is a great improvement over present technology. More importantly, the increased specific energy comes with improved efficiency, further reducing power system mass. The limit of 15 kJ/kg is due to strain limit in the high-purity aluminium filaments. The specific energy can be increased to 50 to 100 kJ/kg by using a stiff external structure. The structure will not be simple, but it is suggested that the benefit of decreased power system mass and volume is worth the initial technical complexity. >

The Main Injector (MI) supports the Tevatron fixed target and proton-antiproton collider modes of operation as well as providing 120 GeV/c resonantly extracted beam for the Main Injector Fixed Target Program. A set of beam transport lines, called A1 and P1, from the Main Injector converge on the injection point of the Tevatron, with the A1 being used to transport 150 GeV/c antiprotons (pbars) to the Tevatron. P1 is used to transport 150 GeV/c protons to the Tevatron, 120 GeV/c protons to the pbar target, and eventually 120 GeV/c resonantly extracted protons to the existing Fixed Target areas.

The use of advanced composites to improve the performance of a railgun armature is considered. The authors discuss the theoretical basis for material selection, review the materials options, and describe the composite of choice. It is shown that composite armatures can be developed that have a mass that is 15% or less of the total mass launched by a railgun. The composite with the best performance as an armature is beryllium-lithium. The toxicity of beryllium makes beryllium-lithium an expensive material to produce and use. It is concluded that aluminum-lithium armatures can be fabricated at a reasonable cost to demonstrate the potential of tailoring the electrothermal properties of metal armature materials. >

The proposed Superconducting Super Collider (SSC) is a high-luminosity proton-proton colliding-beam accelerator, unique in the world, providing access to particle collision energies at least an order of magnitude greater than are available at existing facilities. The design of the SSC has been previously described in the Conceptual Design Report.1 Although not the final SSC design, this paper updates the previous design to include the changes due to the change in cell phase advance from 60 to 90 degrees, and particularly emphasizes the underlying accelerator physics issues which are involved in the SSC. A brief history of the SSC program is given followed by detailed design considerations.

We have developed and demonstrated a novel method of commutating direct current out of a standard vacuum interrupter. The technique uses a high-current, gate-turn-off thyristor in series with the interrupter to extinguish the arc and allow the interrupter to clear. The commutation method has been used to design and fabricate a continuous duty switch that will switch off 1000 A in 100µs and develop 25 kV at a repetition rate of 5 Hz. We have completed preliminary tests and present the important design relationships and test data in this paper.

The MAPPS (MegAmpere Pulsed Power Supply) demonstration tests are described, and the results are reviewed. The observed limits to the switch performance and methods to improve performance are discussed. Testing of the 100 kA demonstrator was completed in July 1986. The measured transformer coupling during operation was 0.99. The switch successfully interrupted 460 A and developed 7.5 kV at five commutations per second. Leakage current through the gate-turn-off thyristor prevented the switch from reaching the 1000 A design goal. The switch performed well up to 460 A, commutating current 290 times during testing. Results indicate that energy storage transformers provide a method to store energy at low currents so that high-purity aluminium or superconducting conductors can be used. >

In order to bring the Fermilab proton-proton colliding-beam facility into operation at the earliest possible time, close coordination between the various aspects of the construction is essential. A possible scenario for how the installation might proceed is presented, and some important consequences for planning in the immediate future are discussed. Some important conclusions which can be drawn from the scenario are presented.