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The UK Government has endorsed the case for autonomous vehicle (AV) technology and its economic benefits in its industrial strategies since 2013. In late 2016 the Science and Technology Committee in the House of Lords (the legislature’s upper chamber) conducted an Inquiry into the policy. We conduct a content analysis of the text corpus of the Inquiry. Drawing from theories of sociotechnical change we explore how it contributes to building a vision of a future AV world embedded in a national economic and technological project. The technology is framed as a solution to societal grand challenges and the Inquiry corpus is dominated by actors committed to the project. Alternative visions, including sceptical interpretations, are present in the corpus, but rare, reflecting the selection process for contributions to the Inquiry. Predominantly, the corpus represents the public as deficient: dangerous drivers, unaware of promised benefits and unduly anxious about the unfamiliar. Their views are marginal in this Parliamentary Inquiry’s findings. AV technology is one of several possible means to pursue wider mobility policy goals of greater safety, affordability, access and sustainability. Our analysis suggests that the pursuit of an AV future risks becoming a goal in itself instead of a means to these broader societal goals.

There have been many surveys of public responses to Autonomous Vehicles (AVs), both reported in peer-reviewed journals and in the mainstream media. People anchor their representations of novel technological objects within their existing experience. What elements of such experience anchor AVs? We review academic English language survey studies from 2015 to 2017 and surveys publicised in UK National newspapers which typically reveal discomfort about the prospect of AVs. Against this background we report the results of our own survey of 11,827 drivers across 11 European countries, addressing attitudes to driving alongside AVs as well as to riding in them. We establish a composite indicator of perceptions of AVs that combines responses on using AVs and sharing the road with them, and analyse its relationship with a set of covariate measures. Respondents’ technological optimism and uptake of driving technology was associated with more positive perceptions of AVs, and measures of respondents’ enjoyment of driving, and how ‘sociable’ they were towards fellow road users, was associated with more negative perceptions. The negative association between driving ‘sociability’ and enthusiasm for AVs was attenuated by levels of general technological optimism. We discuss the difficulties in researching public responses to novel technological objects and make suggestions for improvement in future survey research on AVs.

The ideal of the self-driving car replaces an error-prone human with an infallible, artificially intelligent driver. This narrative of autonomy promises liberation from the downsides of automobility, even if that means taking control away from autonomous, free-moving individuals. We look behind this narrative to understand the attachments that so-called ‘autonomous’ vehicles (AVs) are likely to have to the world. Drawing on 50 interviews with AV developers, researchers and other stakeholders, we explore the social and technological attachments that stakeholders see inside the vehicle, on the road and with the wider world. These range from software and hardware to the behaviours of other road users and the material, social and economic infrastructure that supports driving and self-driving. We describe how innovators understand, engage with or seek to escape from these attachments in three categories: ‘brute force’, which sees attachments as problems to be solved with more data, ‘solve the world one place at a time’, which sees attachments as limits on the technology’s reach and ‘reduce the complexity of the space’, which sees attachments as solutions to the problems encountered by technology developers. Understanding attachments provides a powerful way to anticipate various possible constitutions for the technology.

Autonomous vehicles promise to introduce artificially intelligent physical agents into uncontrolled social spaces for the first time. Public attitudes suggest uncertainty about the technology, but existing research focuses too much on engineering public acceptance instead of engaging with public concerns. I suggest that autonomous vehicles are a test case of the relationship between the public and artificial intelligence technologies and argue for the importance of a deeper, more carefully theorized understanding of public responses. This chapter reports a series of surveys designed to contribute to that effort.

Automated vehicles (AVs) have the potential to cause profound shifts across a wide range of areas of human life, including economic structures, land use, lifestyles and personal well-being. Most current social science on AVs is\ud narrowly framed. Research on public attitudes has focused on whether people are likely to accept and use AVs. We\ud contend that failing to anticipate a wider range of profound social implications may have serious negative\ud consequences, and that social scientists from a range of disciplinary perspectives can provide invaluable insights.\ud Our conclusions are the product of a workshop in London held in 2018 to discuss the place of social science research\ud in relation to the development of AVs. This paper summarises a core selection of our concerns, interests, theoretical\ud and substantive points of reference and aspirations for a constructive role in this field of research and development.

A windowless hydrogen gas target of nominal thickness $10^{19}$ cm$^{-2}$ is an essential component of the DarkLight experiment, which is designed to utilize the megawatt electron beam at an Energy Recovery Linac (ERL). The design of such a target is challenging because the pressure drops by many orders of magnitude between the central, high-density section of the target and the surrounding beamline, resulting in laminar, transitional, and finally molecular flow regimes. The target system was assembled and operated at Jefferson Lab's Low Energy Recirculator Facility (LERF) in 2016, and subsequently underwent several revisions and calibration tests at MIT Bates in 2017. The system at dynamic equilibrium was simulated in COMSOL to provide a better understanding of its optimal operation at other working points. We have determined that a windowless gas target with sufficiently high density for DarkLight's experimental needs is feasible in an ERL environment., 11 pages, 14 figures; v2: minor improvements; v3: author list updated; v4: minor revision

This chapter is about the relationship between three subjects: indigenous peoples, international institutions, and the literature about them. It explores the representational practices in the literature. The chapter expresses that representations of indigenous peoples are constructed through relationships, positive and negative, to modernity. It focuses on the institutional contexts in which the issues of indigenous peoples have been talked about and acted upon. The chapter considers the resistance by indigenous peoples not only to the representational constructs, but also to the reflexivity of institutional action. It explores how the issue of participation by indigenous peoples has been taken up by international institutions. There has been a phenomenal growth in the literature on indigenous people's rights in the period after 1971. The salient characteristic of this institutional literature, from 1945 through to the present, is its pragmatism. The most important site for the application of the contemporary techniques of pragmatic engagement has been the concept of self-determination.

For a high-brightness electron beam with high bunch charge traversing a recirculation beam line, coherent synchrotron radiation and space charge effects may result in microbunching instability (MBI). Both tracking simulation and Vlasov analysis for an early design of a circulator cooler ring (CCR) for the Jefferson Lab Electron Ion Collider (JLEIC) reveal significant MBI [Ya. Derbenev and Y. Zhang, Proceedings of the Workshop on Beam Cooling and Related Topics, COOL’09, Lanzhou, China, 2009 (2009), FRM2MCCO01]. It is envisioned that the MBI could be substantially suppressed by using a magnetized beam. In this paper we have generalized the existing Vlasov analysis, originally developed for a nonmagnetized beam (or transversely uncoupled beam), to the description of transport of a magnetized beam including relevant collective effects. The new formulation is then employed to confirm prediction of microbunching suppression for a magnetized beam transport in the recirculation arc of a recent JLEIC energy recovery linac (ERL) based cooler design for electron cooling. It is found that the smearing effect in the longitudinal beam phase space originates from the large transverse beam size as a nature of the magnetized beams and becomes effective through the x-z correlation when the correlated distance is larger than the microbunched scale. As a comparison, MBI analysis of the early design of JLEIC CCR is also presented in this paper.

In this paper we demonstrate that societal psychology makes a unique contribution to the study of change through its focus on the 'contextual politics' of change, examining the different interests at stake within any social context. Societal psychology explores the contexts which promote or inhibit social and societal change and can be seen as a bridge between social and political psychology. It focuses on how the context shapes the ways in which societal change is understood, supported or resisted. To understand the intellectual rationale of societal psychology, and how it aims to foster societal change, we first consider the history of the discipline. Second, we consider what is meant by 'context', as understanding the environment of change is the hallmark of societal psychology. Third, we lay out three distinct features of a societal psychological approach to change: the politics of change; interventions and planned change; emergent change processes. Finally, the paper examines possible future developments of societal psychology and its role in understanding and creating societal change, alongside its place within the wider canon of social and political psychology.

The coherent synchrotron radiation (CSR) of a high-brightness electron beam traversing a series of dipoles, such as transport or recirculation arcs, may result in beam phase space degradation. On one hand, CSR can perturb electron transverse motion in dispersive regions along the beam line and possibly cause emittance growth. On the other hand, the CSR effect on the longitudinal beam dynamics could result in microbunching instability. For transport arcs, several schemes have been proposed to suppress the CSR-induced emittance growth. Correspondingly, a few scenarios have been introduced to suppress CSR-induced microbunching instability, which however mostly aim for linac-based machines. In this paper we provide sufficient conditions for suppression of CSR-induced microbunching instability along transport or recirculation arcs. Examples are presented with the relevant microbunching analyses carried out by our developed semianalytical Vlasov solver [C.-Y. Tsai, D. Douglas, R. Li, and C. Tennant, Linear microbunching analysis for recirculation machines, Phys. Rev. ST Accel. Beams 19, (2016)]. The example lattices include low-energy ($\ensuremath{\sim}100\text{ }\text{ }\mathrm{MeV}$) and high-energy ($\ensuremath{\sim}1\text{ }\text{ }\mathrm{GeV}$) recirculation arcs, and medium-energy compressor arcs. Our studies show that lattices satisfying the proposed conditions indeed have microbunching gain suppressed. Beam current dependences of maximal CSR microbunching gains are also demonstrated, which should help outline a beam line design for different scales of nominal currents. We expect this analysis can shed light on the lattice design approach that aims to control the CSR-induced microbunching.

Microbunching instability (MBI) has been one of the most challenging issues in designs of magnetic chicanes for short-wavelength free-electron lasers or linear colliders, as well as those of transport lines for recirculating or energy-recovery-linac machines. To quantify MBI for a recirculating machine and for more systematic analyses, we have recently developed a linear Vlasov solver and incorporated relevant collective effects into the code, including the longitudinal space charge, coherent synchrotron radiation, and linac geometric impedances, with extension of the existing formulation to include beam acceleration. In our code, we semianalytically solve the linearized Vlasov equation for microbunching amplification factor for an arbitrary linear lattice. In this study we apply our code to beam line lattices of two comparative isochronous recirculation arcs and one arc lattice preceded by a linac section. The resultant microbunching gain functions and spectral responses are presented, with some results compared to particle tracking simulation by elegant (M. Borland, APS Light Source Note No. LS-287, 2002). These results demonstrate clearly the impact of arc lattice design on the microbunching development. The underlying physics with inclusion of those collective effects is elucidated and the limitation of the existing formulation is also discussed.

The Polarized Electrons for Polarized Positrons experiment at the injector of the Continuous Electron Beam Accelerator Facility has demonstrated for the first time the efficient transfer of polarization from electrons to positrons produced by the polarized bremsstrahlung radiation induced by a polarized electron beam in a high-$Z$ target. Positron polarization up to 82\% have been measured for an initial electron beam momentum of 8.19~MeV/$c$, limited only by the electron beam polarization. This technique extends polarized positron capabilities from GeV to MeV electron beams, and opens access to polarized positron beam physics to a wide community., Comment: 5 pages, 4 figures

From the early days of free-electron lasers (FELs), the idea of lasing at wavelengths where gain media had not previously existed was one of the most attractive aspects of these devices. The spectral region in the soft X-ray was both inviting, due to the exciting physics one could do with such a source, and challenging, due to the need for a very bright electron beam (high charge density), very high gain to overcome cavity losses, and the cost of providing all this at very high electron beam energies with high-duty-cycle electron beams. Electron beam brightness is defined as the ratio of the peak current to the product of the horizontal and vertical normalized emittances. The normalized electron beam emittance is the product of the rms transverse size and momentum spread. High gain is usually obtained using a very long undulator, which requires a very small energy spread in addition to the small transverse emittance. Electron beams in the 1970s generally provided either low peak current or large energy sp...

Advances in superconducting linac technology offer the possibility of an upgrade of the Jefferson Lab Free Electron Laser (JLab FEL) facility to an oscillator-based VUV-FEL that would produce 6 × 1012 coherent 100 eV photons per pulse at multi-MHz repetition rates in the fundamental. In this paper we present novel designs that are verified by model calculations which have themselves been validated by comparison with experimental performance measurements using oscillator-based continuous-wave free electron lasers (FELs) operating in the IR and UV, with sub-picosecond pulses up to 75 MHz and producing harmonics upwards of 10 eV. The accelerator uses an energy recovered linac design for efficiency of operation, and high gain per pass in the oscillator. The fully coherent nature of the source results in peak and average brightness values that are several orders of magnitude higher than storage rings.

A new generation of light sources is now coming on line to address more fundamental scientific challenges in the realms of the ultra-small and ultra-fast, as well as in dynamics. At Jefferson Lab we have developed an Energy Recovered Linac [1,2] based light source that provides tunable sub-ps and synchronized pulses of IR and THz light not available elsewhere. In SRN 13.4 (2000), we reported on an earlier incarnation of this light source [2], and in the past seven years it has undergone a major upgrade [3].

In an experiment conducted on the Jefferson Laboratory IR free-electron laser driver, the effects of coherent synchrotron radiation (CSR) on beam quality were studied. The primary goal of this work was to explore CSR output and effect on the beam with variation of the bunch compression in the IR recirculator. Here we examine the impact of CSR on the average energy loss as a function of bunch compression as well as the impact of CSR on the energy spectrum of the bunch. Simulation of beam dynamics in the machine, including the one-dimensional CSR model, shows very good agreement with the measured effect of CSR on the average energy loss as a function of compression. Finally, a well-defined structure is observed in the energy spectrum with a feature in the spectrum that varies as a function of the compression. This effect is examined in simulations, as well, and a simple explanation for the variation is proposed.

This paper is a compilation of several presentations on multipass beam breakup (BBU) in energy recovery linacs (ERLs) given at the 32nd Advanced ICFA Beam Workshop on ERLs. The goal of this paper is to summarize the progress achieved in analytical, numerical, and experimental studies of the instability and outline available and proposed BBU mitigation techniques. In this paper, a simplified theory of multipass BBU in recirculating linacs is presented. Several BBU suppression techniques and their working principles are discussed. The paper presents an overview of available BBU codes. Results of experimental studies of multipass BBU at the Jefferson Laboratory (JLab) FEL Upgrade are described.

A new THz/IR/UV photon source at Jefferson Lab is the first of a new generation of light sources based on an Energy-Recovered, (superconducting) Linac (ERL). The machine has a 160 MeV electron beam and an average current of 10 mA in 75 MHz repetition rate hundred femtosecond bunches. These electron bunches pass through a magnetic chicane and therefore emit synchrotron radiation. For wavelengths longer than the electron bunch the electrons radiate coherently a broadband THz ∼ half cycle pulse whose average brightness is >5 orders of magnitude higher than synchrotron IR sources. Previous measurements showed 20 W of average power extracted [Carr, et al., Nature 420 (2002) 153]. The new facility offers simultaneous synchrotron light from the visible through the FIR along with broadband THz production of 100 fs pulses with >200 W of average power. The FELs also provide record-breaking laser power [Neil, et al., Phys. Rev. Lett. 84 (2000) 662]: up to 10 kW of average power in the IR from 1 to 14 μm in 400 fs pulses at up to 74.85 MHz repetition rates and soon will produce similar pulses of 300–1000 nm light at up to 3 kW of average power from the UV FEL. These ultrashort pulses are ideal for maximizing the interaction with material surfaces. The optical beams are Gaussian with nearly perfect beam quality. See www.jlab.org/FEL for details of the operating characteristics; a wide variety of pulse train configurations are feasible from 10 ms long at high repetition rates to continuous operation. The THz and IR system has been commissioned. The UV system is to follow in 2005. The light is transported to user laboratories for basic and applied research. Additional lasers synchronized to the FEL are also available. Past activities have included production of carbon nanotubes, studies of vibrational relaxation of interstitial hydrogen in silicon, pulsed laser deposition and ablation, nitriding of metals, and energy flow in proteins. This paper will present the status of the system and discuss some of the discoveries we have made concerning the physics performance, design optimization, and operational limitations of such a first generation high power ERL light source.

Jefferson Lab operates a pair of oscillator-based continuous-wave Free Electron Lasers (FELs) as a linac-based next generation light source with pulse repetition rates up to 75 MHz. The facility uses an energy recovered linac design for efficiency of operation. Recent advances in superconducting technology have been implemented to produce higher acceleration gradients in the linac to produce higher electron beam energies that result in higher photon energies. Thus, while the system originally operated only in the IR, it now covers the photon energy range from the UV to THz, with harmonics upwards of 10 eV with an average spectral flux that is calculated to be 5x1017 photons/sec/0.1%BW. Pulse lengths are in the sub-picosecond regime, and the fully coherent nature of the source, both transversely and longitudinally, results in peak and average brightness values that are several orders of magnitude higher than storage rings. The system provides an R&D test-bed for studies of electron beam dynamics in a regime appropriate for next generation light sources operating at MHz repetition rates.

High power, relativistic electron beams from energy recovery linacs have great potential to realize new experimental paradigms for pioneering innovation in fundamental and applied research. A major design consideration for this new generation of experimental capabilities is the understanding of the halo associated with these bright, intense beams. In this Letter, we report on measurements performed using the 100 MeV, 430 kWatt CW electron beam from the energy recovery linac at the Jefferson Laboratory's Free Electron Laser facility as it traversed a set of small apertures in a 127 mm long aluminum block. Thermal measurements of the block together with neutron measurements near the beam-target interaction point yielded a consistent understanding of the beam losses. These were determined to be 3 ppm through a 2 mm diameter aperture and were maintained during a 7 hour continuous run., Comment: 10 pages, 5 figures

Tests were performed to pass a 100 MeV, 430 kWatt c.w. electron beam from the energy-recovery linac at the Jefferson Laboratory's FEL facility through a set of small apertures in a 127 mm long aluminum block. Beam transmission losses of 3 p.p.m. through a 2 mm diameter aperture were maintained during a 7 h continuous run., United States. Dept. of Energy (Contract DE-AC05-060R23177), United States. Dept. of Energy (MIT Nuclear Contract DE-FG02-94ER40818), Commonwealth of Virginia

We report measurements of photon and neutron radiation levels observed while transmitting a 0.43 MW electron beam through millimeter-sized apertures and during beam-off, but accelerating gradient RF-on, operation. These measurements were conducted at the Free-Electron Laser (FEL) facility of the Jefferson National Accelerator Laboratory (JLab) using a 100 MeV electron beam from an energy-recovery linear accelerator. The beam was directed successively through 6 mm, 4 mm, and 2 mm diameter apertures of length 127 mm in aluminum at a maximum current of 4.3 mA (430 kW beam power). This study was conducted to characterize radiation levels for experiments that need to operate in this environment, such as the proposed DarkLight Experiment. We find that sustained transmission of a 430 kW continuous-wave (CW) beam through a 2 mm aperture is feasible with manageable beam-related backgrounds. We also find that during beam-off, RF-on operation, multipactoring inside the niobium cavities of the accelerator cryomodules is the primary source of ambient radiation when the machine is tuned for 130 MeV operation., 9 pages, 11 figures, submitted to Nuclear Instruments and Methods in Physics Research Section A

Jefferson Lab has - for over a decade - been operating high power IR and UV FELs using CW energy recovering linacs based on DC photocathode electron sources and CEBAF SRF technology. These machines have unique combinations of beam quality, power, and operational flexibility, and thus offer significant opportunity for experiments that use low and medium energy (several tens - few hundreds of MeV) electron beams. We will describe the systems and detail their present and near-term (potential) performance. Recent internal-target analysis and validation testing will be discussed, and schemes for single- and two-pass fixed target operation described. An introduction to subsequent discussions of beam quality and upgrade paths to polarized operation/higher energy will be given.

Operation of the JLab IR Upgrade FEL at CW powers in excess of 10 kW requires sustained production of high electron beam powers by the driver ERL. This in turn demands attention to numerous issues and effects, including: cathode lifetime; control of beamline and RF system vacuum during high current operation; longitudinal space charge; longitudinal and transverse matching of irregular/large volume phase space distributions; halo management; management of remnant dispersive effects; resistive wall, wake-field, and RF heating of beam vacuum chambers; the beam break up instability; the impact of coherent synchrotron radiation (both on beam quality and the performance of laser optics); magnetic component stability and reproducibility; and RF stability and reproducibility. We discuss our experience with these issues and describe the modus vivendi that has evolved during prolonged high current, high power beam and laser operation.

Particle beam modeling in accelerators has been the focus of considerable effort since the 1950s. Many generations of tools have resulted from this process, each leveraging both prior experience and increases in computer power. However, continuing innovation in accelerator technology results in systems that are not well described by existing tools, so the software development process is on-going. We discuss a novel response to this situation, which was encountered when Jefferson Lab began operation of its energy-recovering linacs. These machines were not readily described with legacy software; therefore a model was built using Microsoft Excel. This interactive simulation can query data from the accelerator, use it to compute machine parameters, analyze difference orbit data, and evaluate beam properties. It can also derive new accelerator tunings and rapidly evaluate the impact of changes in machine configuration. As it is spreadsheet-based, it can be easily user-modified in response to changing requirements. Examples for the JLab IR upgrade FEL are presented.

In recirculating accelerators, and, in particular, energy-recovery linacs, the maximum current can be limited by multipass, multibunch beam breakup (BBU), which occurs when the electron beam interacts with the higher-order modes (HOMs) of an accelerating cavity on the accelerating pass and again on the energy recovering pass. This effect is of particular concern in the design of modern high average current energy-recovery accelerators utilizing superconducting rf technology. Experimental characterization and observations of the instability at the Jefferson Laboratory 10 kW free electron laser (FEL) are presented. Measurements of the threshold current for the instability are made under a variety of beam conditions and compared to the predictions of several BBU simulation codes. This represents the first time in which the codes have been experimentally benchmarked. With BBU posing a threat to high current beam operation in the FEL driver, several suppression schemes were developed. These include direct damping of the dangerous HOM using cavity feedback and modifying the electron beam optics so as to reduce the coupling between the beam and mode. Both methods were shown to increase the threshold current for stability. Beam optical suppression techniques, in particular, have proved to be so effective that they are routinely used in the normal operations of the FEL Upgrade Driver.

In recirculating accelerators, and in particular energy recovery linacs (ERLs), the maximum current can been limited by multipass, multibunch beam breakup (BBU), which occurs when the electron beam interacts with the higher-order modes (HOMs) of an accelerating cavity on the accelerating pass and again on the energy recovered pass. This effect is of particular concern in the design of modern high average current energy recovery accelerators utilizing superconducting RF technology. Experimental observations of the instability at the Jefferson Laboratory 10 kW Free-Electron Laser (FEL) are presented. Measurements of the threshold current for the instability are presented and compared to the predictions of several BBU simulation codes. With BBU posing a threat to high current beam operation in the FEL Driver, several suppression schemes were developed. These include direct damping of the dangerous HOMs and appropriately modifying the electron beam optics. Preliminary results of their effectiveness in raising the threshold current for stability are presented.

Energy Recovering Linacs (ERLs) offer an attractive alternative as drivers for light sources as they combine the desirable characteristics of both storage rings (high efficiency) and linear accelerators (superior beam quality). Using superconducting RF technology allows ERLs to operate more efficiently because of the inherent characteristics of SRF linacs, namely that they are high gradient-low impedance structures and their ability to operate in the long pulse or CW regime. We present an overview of the physics challenges encountered in the design and operation of ERL based light sources with particular emphasis on those issues related to SRF technology. These challenges include maximizing a cavity's Q o to increase cryogenic efficiency, maintaining control of the cavity field in the presence of the highest feasible loaded Q and providing adequate damping of the higher-order modes (HOMs). If not sufficiently damped, dipole HOMs can drive the multipass beam breakup (BBU) instability which ERLs are particularly susceptible to. Another challenge involves efficiently extracting the potentially large amounts of HOM power that are generated when a bunch traverses the SRF cavities and which may extend over a high range of frequencies. We present experimental data from the Jefferson Lab FEL Upgrade, a 10 mA ERL light source presently in operation, aimed at addressing some of these issues. We conclude with an outlook towards the future of ERL based light sources.

The multipass, multibunch beam breakup (BBU) instability imposes a potentially severe limitation to the average current that can be accelerated in an energy-recovery linac. Simulation results for Jefferson Lab’s free electron laser (FEL) upgrade driver are presented which predict the occurrence of BBU below the nominal operating current of the machine. In agreement with simulation, BBU was observed and preliminary measurements to identify the higher-order mode causing the instability are shown. In addition, measurements performed to experimentally determine the threshold current are described. Using a newly developed two-dimensional BBU simulation code, we study the effect of optical suppression techniques, first proposed in 1980 [R. E. Rand and T. I. Smith, Part. Accel. 11, 1 (1980)PLACBD0031-2460], on the threshold current of the FEL. Specifically we consider the effect of (1) reflecting the betatron planes about an axis that is at 45° between the vertical and horizontal axes and (2) rotating the betatron planes by 90°. In two-pass recirculators, a 90° rotation can be effective at increasing the threshold current for BBU. The successful installation of a five skew-quadrupole reflector in the backleg of the FEL has been shown to be effective at suppressing the instability and comments on preliminary operational experience will be given.

Magnetic measurements have been performed on several families of dipoles for the 10 kW IR-FEL presently under construction at the Thomas Jefferson National Accelerator Facility. The requirements for these magnets include varying field strengths, large horizontal apertures and parts in 10,000 field homogeneity as well as setability of core and integrated field. Measurements were made to quantify the magnets according to these requirements and to determine the hysteresis protocol, ramp rate dependence, and field clamp settings that are used. This paper will describe the results of these measurements and the procedures used to accomplish them.