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Engineering engagement programs use service learning and community engagement pedagogies that require a real-world situated problem in which the community partners who experience those problems are integral to those spaces. Despite community partners being integral to engineering engagement programs, research on community partner perspectives is vastly unrepresented in literature Therefore, the goal of this work is to investigate engineering engagement programs from the perspective of the community partners by answering the research question: what meaning do community partners make of their experience in engineering engagement programs? This study describes a qualitative research inquiry in which interviews with three community partners from three different engineering engagement programs were conducted and analyzed for community partner meaning. Using a framework developed by Zittoun and Brinkmann for meaning making, this study presented several themes associated with pragmatic, semantic, and existential meanings made by community partners within this study (2012).Findings from this study suggest implications for expansions of existing frameworks of constituents and components of engineering engagement programs, as well as potential opportunities to more deeply engaging community partners the assessment of student contributions and trajectories as a function of participation in EEPs. Additionally, findings from this study suggest an opportunity to investigate communication and thinking between students and community partners to better support the experience of the community partner (and potentially, the learning of the students). Lastly, findings from this study suggest that participation in EEPs presents the opportunity for community partners to learn by doing which can be more deeply investigated to begin addressing the gap in the literature associated with community partners in research on engineering engagement spaces.

Socially engaged design programs, community development coalitions, and intentional and unintentional design spaces are rich with expertise and thinkers who are developing solutions to very pressing, yet complicated problems. Little research has been conducted on the expertise and sense-making of the community partners who participate in these situations. The goal of this research endeavor is to unpack the ways various community partners make meaning of their design experiences by answering the question: What evidence of system’s thinking can be seen in the way community partners describe their work or context? A qualitative research study was conducted in which three community partners were interviewed at various points during their engagement with socially engaged design programs. They demonstrated their systems thinking ability most strongly across the following domains: differentiate and qualify elements, explore multiple perspectives, consider issues appropriately, recognize systems, identify and characterize relationships. These findings imply that the community partners are not only capable of systems thinking but have the potential to be more deeply involved in developing solutions within these settings. Future studies should investigate systems thinking beyond socially engaged design in formal settings and should consider investigation protocols that more directly surface systems thinking domains. Overall, this study contributes to existing work in systems thinking by calling for a more expansive and inclusive engagement of community partners in socially engaged work.

Linac4 will be equipped with a low energy chopper and an energy modulation system to tailor the beam structure to the needs of the PS Booster. This allows optimizing the PS Booster machine performance and reducing beam losses around the injection. In particular, an active longitudinal painting scheme becomes possible for the most demanding high brightness and high intensity beams. This implies that an interface between the low level RF systems of the two machines has to be designed carefully to make sure that the beam generated by Linac4 suits the challenging timing requirements. This reports summarizes the requirements from the Booster side to make full use of the possibilities provided by the chopper and the energy ramping system. Functional descriptions of possible interfaces between the two machines involved are sketched and the arguments to choose one of the schemes as baseline for implementation are given.

To understand one of the contributions to the intensity limitations of the CERN Proton Synchrotron Booster (PSB) in view of its operation with beams from Linac 4, the impedance of the machine has been characterized. Measurements of tune shift as a function of the intensity have been carried out in order to estimate the low frequency imaginary part of the impedance. Since the PSB is a low energy machine, these measurements have been done at two different energies, so as to enable us to disentangle the effect of the indirect space charge and resistive wall from the contribution of the machine impedance. An estimation of the possible resonant peaks in the impedance spectrum has been made by measuring a fast instability in Ring4.

The motivation for the construction of CERN Linac4 is to improve the performance of the PSB by raising the injection energy and implementing a new H- charge exchange multiturn injection scheme. Lattice perturbations introduced by the new injection hardware are described. Strategies to mitigate the consequences, first by minimizing the additional focusing introduced and, by compensating the residual perturbation, are reported.

The Multi-Turn Extraction(MTE)1 at the PS requires, from the PSB, a beam(up to 6.5 1012 protons/ring) with a large horizontal emittance to better produce the five beamlets and a vertical emittance as small as possible. The ways to produce this beam and adjust the parameters are described in this note.

The CERN Proton Synchrotron Booster (PSB) has been running for more than 30 years. Originally designed to accelerate particles from 50 to 800 MeV, later upgradedto an energy of 1 GeV and finally 1.4 GeV, it is steadily being pushed to its operational limits. One challenge is the permanent demand for intensity increase, in particular for CNGS and ISOLDE, but also in view of Linac4. As it is an accelerator working with very high space charge during the low energy part of its cycle, its operational conditions have to be precisely tuned. Amongst other things resonances must be avoided, stop band crossings optimised and the machine impedance minimised. Recently, an operational intensity record was achieved with >4.25×1013 protons accelerated. An orbit correction campaign performed during the 2007/2008 shutdown was a major contributing factor to achieving this intensity. As the PSB presently has very few orbit correctors available,the orbit correction has to be achieved by displacing and/or tilting some of the defocusing quadrupoles common to all 4 PSB rings. The contributing factors used to optimise performance will be reviewed.

The commissioning of CERN's ion injector complex [1] to allow 1.1 PeV collisions of ions in LHC is well under way. After the Low Energy Ion Ring (LEIR) in 2005 [2] and the Proton Synchrotron (PS) in 2006 [3], the Super Proton Synchrotron (SPS) has now been commissioned with the 'Early' ion beam, which should give a luminosity of $5×10^{25}cm^{-2}s^{-1}$ in the LHC. This paper summarizes the operation in 2007 of all the machines involved in the ion injection chain.

Electron cooling is central in the preparation of dense bunches of lead beams for the LHC. Ion beam pulses from the LINAC3 are transformed into short highbrightness bunches using multi-turn injection, cooling and accumulation in the Low Energy Ion Ring, LEIR [1]. The cooling process must therefore be continuously monitored in order to guarantee that the lead ions have the required characteristics in terms of beam size and momentum spread. In LEIR a number of systems have been developed to perform these measurements. These include Schottky diagnostics, ionisation profile monitors and scrapers. Along with their associated acquisition and analysis software packages these instruments have proved to be invaluable for the optimisation of the electron cooler.

At the end of the 2007 run, orbit measurements were carried out in the 4 rings of the PS Booster (PSB) for different working points and beam energies. The aim of these measurements was to provide the necessary input data for a PSB realignment campaign during the 2007/2008 shutdown. Currently, only very few corrector magnets can be operated reliably in the PSB; therefore the orbit correction has to be achieved by displacing (horizontally and vertically) and/or tilting some of the defocusing quadrupoles (QDs). In this report we first describe the orbit measurements, followed by a detailed explanation of the orbit correction strategy. Results and conclusions are presented in the last section.

The LEIR machine is being modified to prepare the ions beam for LHC. As this machine will be used some weeks a year to prepare the beams for LHC in the injectors complex and for LHC physics, it is propose to use it also for cancer therapy and for radio-biological tests for the remaining time. This note reviews the motivation, the possibilities and proposes some thoughts on how to proceed.

The CERN Low Energy Ion Ring (LEIR) commissioning started in the year 2005. O4+and Pb54+ion beams are transferred at 4.2 MeV/nucleon from Linac 3 to LEIR through a low energy transfer line, for which the constraints and the resulting optics design are presented. First trajectory and dispersion measurements agreed only poorly with the theoretical model. Iterations of a refined optics model and further measurements improved the agreement between experimental observations and expectations. In particular, the effect of quadrupole errors in the line dipole magnets is discussed.

The Low Energy Ion Ring (LEIR) is a low energy ion cooling and accumulation ring and serves to compress long ion pulses from Linac3 into high density bunches suitable for LHC ion operation. Issues of the LEIR lattice are to fulfil all constraints with a small number of quadrupoles and compensations of perturbations due to an electron cooler and gradients seen by the beam in the bending magnets during the ramp. Furthermore, experimental investigations via orbit response measurements will be reported.

The requirements for nominal and ultimate LHC beams in the CERN PS-Booster were specified in 1994 and served as input for the definition of the "PS conversion for LHC" project. Already during the upgrade project and also after its completion in 2000, the beam intensities to be provided from the PS Booster were increased in order to compensate for changes on the LHC machine, the beam production scheme in the PS and for nonanticipated beam losses along the injector chain. In order to improve the beam brightness, to be compatible with the increased requirements, extensive machine studies have taken place on the PS-Booster. The working point was changed to reduce the influence of systematic resonances and the injection line optics was re-matched to improve the injection efficiency. The paper summarizes briefly the evolution of the performance requirements. The various measures undertaken to improve the LHC beam quality are outlined and the present performance achieved in the PS Booster is presented.

The new LEIR cooler with a variable profile of the electron beam and electrostatic bending was commissioned in 2005-2006. In this paper we present our experience with the commissioning of the new device as well as the first results of the ion beam Pb +54 cooling with a high-intensity variable-density electron beam.

This specification, drawn up by the instrumentation specification board 2, describes the requirements concerning orbit and trajectory measurements in the PS machine. The orbit measurement and the trajectory measurement are both indispensable in order to be able to guarantee the correct beam quality for beams like LHC, the future Grand Sasso beam, the nTOF beam and surely the combined operation of the nTOF beam and the East Area beam.

This paper reports on experiments with a new working point for the CERN PS Booster (PSB), performed during a dedicated machine development (MD) session following the 2003 run. For the experiments, we have set up the PSB with (Qh = 4.17,Qv = 4.23), and compensated only the 2Qv = 9 resonance. We compare the performance of the PSB to the one using operational settings (Qh = 4.17,Qv = 5.23). We have studied the performance using ISOLDE and LHC type beams. Furthermore, we have measured the strength of some of the resonance driving terms.

High brightness and high intensity beams are required from the PS Booster for LHC, CNGS and ISOLDE operation. The large space charge tune spreads associated with these beams, especially at injection, require an optimised resonance compensation scheme to avoid beam blow-up and subsequent beam losses. For this a detailed knowledge on strength and phase of resonance driving terms is needed. A new measurement system has been installed to determine resonance driving terms from turn-by-turn beam position data using fast Fourier transform. The multi-turn acquisition system as well as the specic measurement conditions at the PS Booster are discussed. As an example, the measurement and compensation of the linear coupling resonance driving term is presented. Excellent agreement between measurement and simulation for resonance phase and strength was found.

A sizeable part of the LHC physics programme foresees lead-lead collisions with a design luminosity of 1027 cm-2 s-1. This will be achieved after an upgrade of the ion injector chain comprising Linac3, LEIR, PS and SPS machines [1,2]. Each LHC ring will be filled in 10 min by almost 600 bunches, each of 7×107 lead ions. Central to the scheme is the Low Energy Ion Ring (LEIR) [3,4], which transforms long pulses from Linac3 into high-brilliance bunches by means of multi-turn injection, electron cooling and accumulation. Major limitations along the chain, including space charge, intrabeam scattering, vacuum issues and emittance preservation are highlighted. The conversion from LEAR (Low Energy Antiproton Ring) to LEIR involves new magnets and power converters, high-current electron cooling, broadband RF cavities, and a UHV vacuum system with getter (NEG) coatings to achieve a few 10-12 mbar. Major hardware changes in Linac3 and the PS are also covered. An early ion scheme with fewer bunches (but each at nominal intensity) reduces the work required for early LHC ion operation in spring 2008.

The LEIR machine is being modified to prepare the ions beam for LHC. As this machine will be used some weeks a year to prepare the beams for LHC, it has been proposed to use it to test the radiobiological effects of hadron impact on cells in view of improving the efficiency and safety of hadron therapy. This note reviews the possibilities offered by the Linac3 and the Lear machine, proposes modifications to machines. Finally we evaluate the resources needed.

To provide efficient deceleration and to produce antiproton beam with the required characteristics two different cooler systems (stochastic and electron) are used in operation on the AD (Antiproton Decelerator) machine. In a near future, an electron cooling system will be used in LEIR (Low Energy Ion Ring) to accumulate ions for LHC. This system will be used for a fast ion beam cooling and stacking. These cooling systems are described.

The creation of hollow bunches in longitudinal phase space, in order to decrease the peak current and hence the transverse direct space charge forces, is an old idea. A new method to create such a hollow distribution at high energy has been simulated and tested experimentally at the PS Booster synchrotron. It is based on are distribution of surfaces in the longitudinal phase space by using a double harmonic RF system. During the process, the beam is transferred from one second harmonic sub-bucket to an other. Low density phase space surfaces from the periphery and high density regions from the centre are exchanged, leading to flat profiles, even after switching off the second harmonic RF system. During the process, the peak current is temporarily increased, which makes it suitable only to improve the situation in a receiving machine (in our case the PS) after transfer. In practice, the set-up of this new scheme turned out to be fast and simple and to yield reliable and reproducible results

The LEIR transfer lines are designed to transport the ion beam from the Linac 3 to LEIR and, after accumulation and acceleration from LEIR to the PS. A part of the transfer line is used for both, injection and extraction. Thus, it is natural to design injection and extraction optics in common. Beside optics constraints, the geometry of the existing machines (Linac 3, LEIR and PS) and transfer tunnels have to be respected. A new proposal for the LEIR transfer lines is presented.

The Brazilian Bioethanol Science and Technology Laboratory (CTBE) one of the laboratories of the Brazilian Center of Research in Energy and Materials (CNPEM) has as one of its main goals contribute to the development of the process of obtaining second generation ethanol ( GII ) mainly from lignin cellulosic fractions of cane sugar. To achieve this goal leads its own line of research, develop partnerships with other public and private institutions or acting as national laboratory offers its facilities of laboratories and process development pilot plant to researchers involved in projects to produce ethanol, energy and chemicals from lignocelluloses materials. The activities of CTBE are based on research and development line that integrates the current process of obtaining first-generation ethanol ( GI ) of the sugars extracted from cane sugar coupled with the second generation process of deconstruction of lignocelluloses fractions (bagasse and straw), enzymatic hydrolysis of cellulose and fermentation of pentose and hexoses. The production of ethanol GII although technically demonstrated, at the present time not achieved results that enable production at competitive costs. The critical barriers to overcome to achieve this goal are: • Pretreatment: efficient fractionation of lignocelluloses material for better recovery and hydrolysis of pentose and cellulignin. • Hydrolases: Obtaining a more efficient and productive hydrolases complex; • Enzymatic hydrolysis: optimization of hydrolysis of cellulose; • Ethanol from pentose: development of pentose fermentation to ethanol. The negative impact of these barriers on the process of obtaining second-generation ethanol will be discussed. The research lines proposed for overcome it and improve the performance of this process integrated with first generation ethanol will be presented.

The overall modifications of the PS complex (Linac3, LEIR, PS) to produce the LHC ion beams is described. While the main emphasis is put on lead, some considerations will be given to other ion species, which are or may be requested. The different systems are reviewed with particular attention to electron cooling, the injection systems and beam lifetime.

The LHC pre-injector complex, comprising Linac 2, the PS Booster (PSB) and the PS, has undergone a major upgrade in order to meet the very stringent requirements of the LHC. Whereas bunches with the nominal spacing and transverse beam brightness were already available from the PS in 1999 [1], their length proved to be outside tolerance due to a debunching procedure plagued by microwave instabilities. An alternative scenario was then proposed, based on a series of bunch-splitting steps in the PS. The entire process has recently been implemented successfully, and beams whose longitudinal characteristics are safely inside LHC specifications are now routinely available. Variants of the method also enable bunch trains with gaps of different lengths to be generated. These are of interest for the study and possible cure of electron cloud effects in both the SPS and LHC. The paper summarizes the beam dynamics issues that had to be addressed to produce beams with all the requisite qualities for the LHC.