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In a fixed-field alternating-gradient (FFAG) accelerator, eliminating pulsed magnet operation permits rapid acceleration to synchrotron energies, but with a much higher beam-pulse repetition rate. Conceived in the 1950s, FFAGs are enjoying renewed interest, fuelled by the need to rapidly accelerate unstable muons for future high-energy physics colliders. Until now a 'scaling' principle has been applied to avoid beam blow-up and loss. Removing this restriction produces a new breed of FFAG, a non-scaling variant, allowing powerful advances in machine characteristics. We report on the first non-scaling FFAG, in which orbits are compacted to within 10 mm in radius over an electron momentum range of 12-18 MeV/c. In this strictly linear-gradient FFAG, unstable beam regions are crossed, but acceleration via a novel serpentine channel is so rapid that no significant beam disruption is observed. This result has significant implications for future particle accelerators, particularly muon and high-intensity proton accelerators. © 2012 Macmillan Publishers Limited. All rights reserved.

The need for real-time monitoring of beam losses, including evaluation of their intensity and localization of their exact position, together with the possibility to overcome the limitations due to the reduced space for the diagnostics, makes exploitation of the Cherenkov effect in optical fibres, one of the most suitable candidates for beam loss monitoring. In this article, we report on the first tests of an optical fibre beam loss monitor based on large numerical aperture pure silica fibres and silicon photomultipliers. The tests were carried out at the ALICE accelerator research and development facility, Daresbury Laboratories, UK. In contrast to the results already published where the fibres are longitudinally placed with respect to the accelerator beam path and the losses are multidirectional charged particle showers, for the first time a dedicated set-up with an incident accelerator beam impinging directly on the optical fibre was used for optimizing the collection efficiency of the Cherenkov effect as a function of the incident angle by changing the fibre direction. For this purpose large core fibres were used together with the latest generation silicon detector instead of the standard photomultiplier tubes commonly used for Cherenkov beam loss monitoring. The experiments described in this contribution aim to demonstrate the suitability of the optical fibre sensor for loss monitoring, to optimize the Collection Efficiency (CE) of the Cherenkov photons inside the fibre as a function of the particle incident angle, to calibrate the sensor and calculate its sensitivity, and to understand the limits of temporal resolution of losses from different bunches in the accelerator.

Three new species of the genus Leprocapsus Poppius from Indonesia, L. irianjayensis n. sp. and L. parvus n. sp. (Irian Jaya), and L. schuhi n. sp. (Sulawesi), are described. A color photograph of the adult and illustration of the antennal segments I and II of each treated taxa, dorsal habitus drawing of L. schuhi, illustration of the male genitalia of L. parvus, and scanning electron micrographs of selected structures of L. irianjayensis, L. schuhi, and L. scutellaris are provided. A key to all known species, diagnosis and the distribution map of the genus Leprocapsus are given.

The New World species of the genus Peritropis are revised, and 17 new species are described: P. amazonica, P. amphicyrta, P. carpinteroi, P. carvalhoi, P. conspersa, P. cornata, P. gorczycai, P. guarani, P. izyai, P. marmorea, P. nicaraguensis. P. plaumanni, P. schaffneri, P. scutellata, P. stobieckii, P. turrialba and P. venezuelaensis. All previously known species from the New World (P. husseyi Knight, P. saldaeformis Uhler, and P. tuberculata McAtee and Malloch) are redescribed, except P. unicolor Carvalho and Rosas for which an English translation of the original description is provided. Illustrations of the male genitalia, a color photograph of the adult of each species, scanning electron micrographs of selected structures of Peritropis husseyi, P. saldaeformis and P. turrialba, and a key to species are provided.

Wake field simulations are performed for given technical designs of the vacuum chamber components for the 6.4 km ILC damping ring, in order to calculate longitudinal wake functions. Modelling of the microwave instability based on multi-turn tracking with many particles is described. A comparison is presented between the potential well distortion found from solving the Haissinski equation and the results of tracking simulations. The threshold for the microwave instability is found for the given designs and lattice parameters.

The procedure for calculating the resistive wall impedance is simplified using Gaussian elimination with a sufficiently large floating point precision. This procedure generalises readily to the multilayer beam pipe wall. We apply this to investigate the effect of NEG coating on the transverse wake field coupling between electron bunches in the ILC damping ring. For a 5 GeV electron beam and 3 cm radius aluminium beam pipe, a 1 μm thick NEG coating is found to increase the impedance around 10 GHz. The wake field over a distance of 300 km around the ring is required for the study of the multi-bunch instabilities. This has to be obtained by Fourier transforming over a very wide range of frequencies. To overcome the computation problem, we developed a way of splitting up the frequencies into three overlapping ranges, and then joining the transforms together to obtain the overall wake field. The results for a few NEG coating thicknesses are presented.

We demonstrate that the normalised phase space can be used to improve the quality of the reconstructed image in phase space tomography. This study uses the Filtered Back Projection (FBP) for reconstruction. We simulate the tomographic projections of a Gaussian phase space distribution in real phase space and in normalised phase space. The reconstruction can be carried out in real phase space directly. It can also be done first in normalised phase space, and then the co-ordinates can be transformed to real phase space. Using FBP, we show that the latter procedure produces images that agree well with the original distribution even when there are only three angles. It also gives better resolution for a more complex distribution, which we simulate with a random collection of Gaussian spots.

The first North American record for Fulvius subnitens Poppius is reported based on one specimen collected in southcentral Virginia. Fulvius anthocoroides (Reuter), Fulvius imbecilis (Say), Fulvius slateri Wheeler, and Fulvius subnitens are diagnosed and described, and color images of adults, updated distributions, a review of feeding habits, and an identification key are provided. For each species, the nomenclatural history and most important citations are given.

This work reports the use of an infrared spectroscopic version of scanning near-field optical microscopy (IR-SNOM) and shows that it is possible to reveal subcellular entities via their chemical constituents in a label-free human oesophageal adenocarcinoma cell (OE33). This work presents the first high spatial resolution (similar to 0.15 mu m) study of features imaged at various wavelengths within a cancer cell. The clear illumination of sub-micron sized moieties within a cell is a major step forward and is a key requirement for understanding cancer and for the study of other diseases and healthy tissue. The stable and tuneable light source was provided by the infrared free electron laser on the ALICE accelerator at Daresbury. The images reveal a structure with a size and wavelength absorption that are consistent with a chromosome and open the possibility of observing other localized structures, such as microvesicles, that play an important role in the development and spread of cancers.

The anomalous magnetic moment of the muon is one of the most precisely measured quantities in experimental particle physics. Its latest measurement at Brookhaven National Laboratory deviates from the Standard Model expectation by approximately 3.5 standard deviations. The goal of the new experiment, E989, now under construction at Fermilab, is a fourfold improvement in precision. Here, we discuss the details of the future measurement and its current status. C 2015 AIP Publishing LLC. [http://dx.doi.org/10.1063/1.4917553]

The plant bug genus Cylapocoris Carvalho, 1954 is revised. Seven new species: Cylapocoris costaricaensis sp. nov., C. cucullatus sp. nov., C. fulvus sp. nov., C. laevigatus sp. nov., C. marmoreus sp. nov., C. plectipennis sp. nov., and C. simplex sp. nov. are described from Costa Rica, Brazil, Ecuador, and Venezuela. The genus Adcylapocoris Carvalho, 1989 is synonymized with Cylapocoris. Five species: C. castaneus (Carvalho, 1989), C. funebris (Distant, 1883), C. pilosus Carvalho, 1954, C. sulinus CarvalhoGomes 1971, and C. tiquiensis Carvalho, 1954 are redescribed. Illustrations of the male genitalia, color photographs of dorsal and lateral views of the adult of most species, scanning electron micrographs of selected structures of C. simplex, and keys to species of the genus Cylapocoris are provided.

Hydrogen sulfide (H2S) is synthesized in perivascular adipose tissue (PVAT) and induces vasorelaxation. We examined whether the sulfur-containing AMP and GMP analogs AMPS and GMPS can serve as the H2S donors in PVAT. H2S production by isolated rat periaortic adipose tissue (PAT) was measured with a polarographic sensor. In addition, phenylephrine-induced contractility of aortic rings with (+) or without (−) PAT was examined. Isolated PAT produced H2S from AMPS or GMPS in the presence of the P2X7 receptor agonist BzATP. Phenylephrine-induced contractility of PAT(+) rings was lower than of PAT(−) rings. AMPS or GMPS had no effect on the contractility of PAT(−) rings, but used together with BzATP reduced the contractility of PAT(+) rings when endogenous H2S production was inhibited with propargylglycine. A high-fat diet reduced endogenous H2S production by PAT. Interestingly, AMPS and GMPS were converted to H2S by PAT of obese rats, and reduced contractility of PAT(+) aortic rings isolated from these animals even in the absence of BzATP. We conclude that (i) AMPS and GMPS can be hydrolyzed to H2S by PAT when P2X7 receptors are activated, (ii) a high-fat diet impairs endogenous H2S production by PAT, (iii) AMPS and GMPS restore the anticontractile effects of PAT in obese animals without P2X7 stimulation.

Fringe fields in multipole magnets can have a variety of effects on the linear and nonlinear dynamics of particles moving along an accelerator beamline. An accurate model of an accelerator must include realistic models of the magnet fringe fields. Fringe fields for dipoles are well understood and can be modelled at an early stage of accelerator design in such codes as MAD8, MADX or ELEGANT. However, usually it is not until the final stages of a design project that it is possible to model fringe fields for quadrupoles or higher order multipoles. Even then, existing techniques rely on the use of a numerical field map, which will usually not be available until the magnet design is well developed. Substitutes for the full field map exist but these are typically based on expansions about the origin and rely heavily on the assumption that the beam travels more or less on axis throughout the beam line. In some types of machine (for example, a non-scaling FFAG such as EMMA) this is not a good assumption. In this paper, a method for calculating fringe fields based on analytical expressions is presented, which allows fringe field effects to be included at the start of an accelerator design project. The magnetostatic Maxwell equations are solved analytically and a solution that fits all orders of multipoles derived. Quadrupole fringe fields are considered in detail as these are the ones that give the strongest effects. Two examples of quadrupole fringe fields are presented. The first example is a magnet in the LHC inner triplet, which consists of a set of four quadrupoles providing the final focus to the beam, just before the interaction point. Quadrupoles in EMMA provide the second example. In both examples, the analytical expressions derived in this paper for quadrupole fringe fields provide a good approximation to the field maps obtained from a numerical magnet modelling code., Comment: 27 pages, 39 figures. The figures are new with respect to the previous version, Several mistakes also corrected

Summary The studies on aphid flights using Johnson's aspirator in the Silesian Province in southern Poland began in 2007. Regularly captured insect species according to the list of 9 aphid species recommended for observation by the Institute of Plant Protection – National Research Institute (IPP – NRI) in Poznan, allowed comparing aphid incidence over the 5-year period. The greatest abundance of aphids was reported in the spring and autumn. The most numerous species were Rhopalosiphum padi (L.) and Anoecia corni (F.). Aphid flight data were regularly posted on the webpage of the IPP – NRI in Poznan to indicate potential risks for growers.

In high chromaticity circular accelerators, rapid decoherence of the betatron motion of a particle beam can make the measurement of lattice and bunch values, such as Courant-Snyder parameters and betatron amplitude, difficult. A method for reconstructing the momentum distribution of a beam from beam position measurements is presented. Further analysis of the same beam position monitor data allows estimates to be made of the Courant-Snyder parameters and the amplitude of coherent betatron oscillation of the beam. The methods are tested through application to data taken on the linear nonscaling fixed field alternating gradient accelerator, EMMA.

This report describes the conceptual design of a proposed free electron laser test facility called CLARA that will be a major upgrade to the existing VELA accelerator test facility at Daresbury Laboratory in the UK. CLARA will be able to test a number of new free electron laser schemes that have been proposed but require a proof of principle experiment to confirm that they perform as predicted. The primary focus of CLARA will be on ultra short photon pulse generation which will take free electron lasers into a whole new regime, enabling a new area of photon science to emerge.

Comefulvius chingonus CarvalhoCarpintero, the only representative of the genus Comefulvius, previously known only from Córdoba Province, Argentina, is recorded from Ecuador. Redescription of Comefulvius is given along with color photographs of the adult and illustrations of the male genitalia.

A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [ P. Raimondi and A. Seryi , Phys. Rev. Lett. 86 , 3779 ( 2001 ) ]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

The genera Peritropisca CarvalhoLorenzato, 1978 and Rewafulvius Carvalho, 1972 are redescribed. A description of a new species of the genus Peritropisca from Indonesia-P. laticostata sp. nov. and a redescription of P. bituberculata CarvalhoLorenzato, 1978 are provided. The genus Euchilofulviella Gorczyca, 1999 is proposed as a junior synonym of Rewafulvius Carvalho, 1972 syn. nov. A color habitus picture of the adult and male genitalia drawings of each treated species are provided. A key to the genus Peritropisca is given.

The genus Xenocylapidius Gorczyca, 1997 is revised. Five new species: Xenocylapidius acutipennis sp. n., Xenocylapidius ater sp. n., Xenocylapidius bimaculatus sp. n., Xenocylapidius gemellus sp. n., and Xenocylapidius rolandi sp. n. are described from Australia and New Caledonia. Illustrations of the male genitalia, color photographs of dorsal and lateral views of the adults of all species, and key to species of the genus Xenocylapidius are provided.

We show that the combination of a scanning near field optical microscope and an infra-red free electron laser yields chemical images with sub-cellular spatial resolution that have the potential to provide a diagnostic for oesophageal adenocarcinoma.

Eight new species of the tribe Bothriomirini are described from the Oriental Region, namely Dashymenia cognata sp. nov., Dashymenia colubrina sp. nov., Dashymenia conspersa sp. nov., Dashymenia tenmalai sp. nov., Dashymenia webbi sp. nov., Dashymeniella spatulatiformis sp. nov., Dashymeniella ulu sp. nov., and Dashymeniella viklundi sp. nov. Five species are redescribed: Bothriomiris dissimulans (Walker), B. lugubris Poppius, B. testaceus Distant, Dashymenia croesus (Distant), and Dashymenia remus (Distant). Illustrations of the male genitalia, a color dorsal habitus photograph of the adult of most species, scanning electron micrographs of selected structures of Bothriomiris dissimulans, Dashymenia tenmalai, Dashymeniella spatulatiformis, and Dashymeniella ulu are given. An identification key to the Oriental genera and keys to species of the genera Bothriomiris, Dashymenia, and Dashymeniella are provided.

The subfamily Cylapinae (Insecta, Heteroptera: Miridae) from India is reviewed. Three tribes, seven genera and nineteen species are cited from the country, keyed and described. Six species are described as new: Fulvius kadapaensis sp. nov., Peritropis kodava sp. nov., Peritropis pathaki sp. nov., Peritropis sangai sp. nov., Peritropis yasunagai sp. nov. and Rhinomiris prathapani sp. nov. A new synonymy is published: Peritropis lewisi (Distant, 1904) (valid name) = Peritropis indicus Gorczyca, 2006b (new junior subjective synonym).

Transfer maps for magnetic components are fundamental to studies of beam dynamics in accelerators. In the work presented here, transfer maps are computed in Taylor form for a particle moving through any specified magnetostatic field by applying an explicit symplectic integrator in a differential algebra code. The techniques developed are illustrated by their application to study the beam dynamics in the electron model for many applications (EMMA), the first nonscaling fixed-field alternating-gradient accelerator ever built. The EMMA lattice has 4 degrees of freedom (strength and transverse position of each of the two quadrupoles in each periodic cell). Transfer maps may be used to predict efficiently the dynamics in any lattice configuration. The transfer map is represented by a mixed variable generating function, obtained by interpolation between the maps for a set of reference configurations: use of mixed variable generating functions ensures the symplecticity of the map. An optimization routine uses the interpolation technique to look for a lattice defined by four constraints on the time of flight at different beam energies. This provides a way to determine the lattice configuration required to produce the desired dynamical characteristics. These tools are benchmarked against data from the recent EMMA commissioning.

We describe a technique for constructing a symplectic transfer map for a charged particle moving through an accelerator component with arbitrary three-dimensional static magnetic field. The transfer map is constructed by symplectic integration; by representing the map at each step of the integration by a mixed-variable generating function, exact symplecticity is ensured. By using an appropriate integration algorithm, there is no necessity to make the paraxial approximation. The technique is illustrated by application (in one degree of freedom) to a quadrupole magnet with strong octupole component and fringe field., Comment: 18 pages, 4 figures

Primary cardiac tumours are very rare (0.02%). Typically fibroelastoma arises from valvular endocardium, nonvalvular locations occur occasionally. Usually fibroelastoma is asymptomatic, however in some cases it may produce small superficial thrombi with substantial risk of embolisation. We report 59 year-old male with left atrial appendage location of papillary fibroelastoma diagnosed during transesophageal echocardiography. Computed tomography confirmed morphological signs typical for this tumour.

Magnetostatic fields in accelerators are conventionally described in terms of multipoles. We show that in two dimensions, multipole fields do provide solutions of Maxwell's equations, and we consider the distributions of electric currents and geometries of ferromagnetic materials required (in idealized situations) to generate specified multipole fields. Then, we consider how to determine the multipole components in a given field. Finally, we show how the two-dimensional multipole description may be extended to three dimensions; this allows fringe fields, or the main fields in such devices as undulators and wigglers, to be expressed in terms of a set of modes, where each mode provides a solution to Maxwell's equations., Comment: Presented at the CERN Accelerator School CAS 2009: Specialised Course on Magnets, Bruges, 16-25 June 2009

We discuss the theory of electromagnetic fields, with an emphasis on aspects relevant to radiofrequency systems in particle accelerators. We begin by reviewing Maxwell's equations and their physical significance. We show that in free space, there are solutions to Maxwell's equations representing the propagation of electromagnetic fields as waves. We introduce electromagnetic potentials, and show how they can be used to simplify the calculation of the fields in the presence of sources. We derive Poynting's theorem, which leads to expressions for the energy density and energy flux in an electromagnetic field. We discuss the properties of electromagnetic waves in cavities, waveguides and transmission lines., Comment: Presented at the CERN Accelerator School CAS 2010: RF for accelerators, Ebeltoft, 8-17 June 2010

Injection of fresh bunches into a storage ring can induce jitter in the stored bunches. For machines demanding beams of very low emittance and high stability, such as the damping rings of a future linear collider or the storage rings of a super flavor factory, this could be a potential performance limitation. We present an analysis, for the International Linear Collider (ILC) damping rings, of the transverse jitter induced on the extracted bunches from the jitter on the injected bunches, with the coupling between bunches mediated by the resistive-wall wakefield of the vacuum chamber. We find that it is important to include details of the local transverse focusing around the ring. We consider the impact of the finite thickness of the beam pipe wall, and of nonevaporable getter coating on the inside surface: in the parameter regime of the ILC damping rings, we find that the results are only slightly modified compared to an approximation to the resistive-wall wakefield based on a single-layer wall of infinite thickness. The results from our simulations indicate a tight specification on the jitter of the injected bunches.

We present an analytical and numerical study of the equations of motion for bunches coupled by transverse wakefields. We base our study on a recent lattice design for the damping rings in the baseline configuration of the International Linear Collider. Using the macroparticle model, and assuming resistive wall wakefield coupling, we present numerical results on the time evolution of the multibunch modes. Decay modes display growth after initial decay, and mode amplitudes exhibit high-frequency oscillations. These phenomena are not expected if the beta function is assumed to have a constant, averaged value. We show analytically that they can come from coupling between modes caused by variation of the beta function in a real lattice. The effect is shown to be comparable to the effect of a nonuniform fill pattern and significantly larger than that of the higher-order mode wakefield localized in the rf cavities. Turning to the case of constant beta function, we develop a more complete treatment of the equations of motion. We derive general formulas for the bunch trajectories, and show that such formulas can only be valid in the limit of small wakefield coupling.

Very low emittances and small beta functions at the interaction point(IP) are needed to achieve the design luminosity of 1036 cm-2 s-1 for a SuperB project. Two rings of 4 and 7 GeV have been designed with the same emittances and damping times. A new Final Focus section has also been designed to strongly squeeze the colliding beams both in the horizontal and the vertical plane at IP, while providing local correction of the large chromaticity and exploiting the large crossing angle and crab waist concepts. Lattice features and chromaticity correction schemes will be discussed here. Dynamic apertures, with damping wigglers similar to those of ILC, will also be presented.

For the International Linear Collider to reach its design luminosity, the damping rings must achieve a vertical emittance that is a factor of two below that achieved in any operating storage ring so far. Magnet alignment, orbit control and coupling correction are therefore critical issues for the ILC damping rings. We present the results of studies of the sensitivity to quadrupole and sextupole alignment errors for a recent lattice design for the damping rings.

A new code to calculate the effects of intrabeam scattering (IBS) has been developed in MATLAB based on the approximation suggested by K. Bane. It interfaces with the Accelerator Toolbox but can also read in lattice functions from other codes. The code has been benchmarked against results from other codes for the ATF that use this approximation or do the calculation in a different way. The new code has been used to calculate the emittance growth due to intrabeam scattering for the lattices currently proposed for the ILC Damping Rings, as IBS is a concern, especially for the electron ring. A description of the code and its user interface, as well as results for the Damping Rings, will be presented.

The injection efficiency of an ILC damping ring is closely tied to its acceptance. To maximize both, one wants a physical aperture as large as possible in the wiggler magnets, as these are likely to be the limiting physical apertures in the ring. On the other hand, a small aperture in the wiggler magnets is needed to achieve the required field profile, a high magnetic field that is very linear over the whole physical aperture of the magnet. Tracking studies were done for all proposed ILC damping ring lattices to determine their required physical apertures. Although a half-aperture of 8 or 10mm had been proposed, our studies showed that, for most lattices, a 16mm half-aperture is required. (For some lattices a 12mm half aperture might suffice.) We present here the results of our studies, which led to adopting a 16mm half-aperture in the current ILC damping ring baseline design.

We use Bane's approximation to the Bjorken-Mtingwa theory of intrabeam scattering to calculate the emittance growth as a function of bunch charge in the KEK ATF. We find that our results are consistent with the experimental data. We then calculate the emittance growth in the NLC Main Damping Rings using the same formulae; we allow for some uncertainty in the ATF data by using two different values for the Coulomb log factor in the formulae for the emittance growth rates. We find that despite the IBS emittance growth, it should still be possible to achieve the specified transverse and longitudinal emittances in the NLC Main Damping Rings at the specified bunch charge.

The Damping Rings for the International Linear Collider have challenging requirements for the acceptance, because of the high average injected beam power and the large beam produced from the positron source. At the same time, the luminosity goals of the collider mean that the natural emittance must be very small, and this makes it particularly difficult to achieve a good dynamic aperture. We describe a design approaches and lattice designs that meet the emittance specification and have a very promising dynamic aperture.