1,555 research outputs found

    An FFAG Transport Line for the PAMELA Project

    Get PDF
    The PAMELA project to design an accelerator for hadron therapy using non-scaling Fixed Field Alternating Gradient (NS-FFAG) magnets requires a transport line and gantry to take the beam to the patient. The NS-FFAG principle offers the possibility of a gantry much smaller, lighter and cheaper than conventional designs, with the added ability to accept a wide range of fast changing energies. This paper will build on previous work to investigate a transport line which could be used for the PAMELA project. The design is presented along with a study and optimisation of its acceptance

    Needs analysis report following the sexual exploitation of children in Rotherham

    Get PDF
    It has been an immense honour to listen to the experiences of the people of Rotherham. The project team received a warm welcome and felt humbled at the extraordinary courage of victims, survivors and their families. We wish to express our heartfelt thanks to everyone who took part in the study. The knowledge and opinions shared by our participants are the foundation of this report. No-one wants to think about what child sexual abuse and exploitation really means. Recognising that children have been humiliated, raped and tortured is extremely distressing. As such, it is no surprise that many felt anger and rage when they understood that those with authority failed to protect vulnerable children and young people. There is a need to face the awful reality that child sexual abuse has always happened. However, in the age of the internet, the number of children at risk of sexual abuse has increased. Those who sexually abuse children are mostly, but not always, men. Not discounting the vast number of boys who have suffered abuse, most of the known victims of sexual abuse are girls. Both victims and perpetrators come from every walk of life. The threat is such that we all have a responsibility to consider what we can do to protect every child in our family and communities. The public criticism of Rotherham Metropolitan Borough Council (RMBC) and South Yorkshire Police, following Professor Jay’s report was right and inevitable. Positively, there have been several examples of how RMBC and South Yorkshire Police have responded to criticism and improved the way they respond to victims and survivors. However, there have also been negative consequences of public scrutiny, with many people in the study reporting that they want to regain pride in their hometown. Those who took part in this study did not shy away from exploring the difficulties they face. Naturally, participants continue to talk about issues of trust, as past mistakes created a sense of vulnerability. However, there is also evidence that healing is taking place. Many participants made suggestions of how they and RMBC could and should collaborate to strengthen, individuals, families and their communities Indeed, there is a determination to meet current and future needs with a sense of collective rigour. Some of these tasks involve developing internal structures, such as communication and the provision of appropriate resources. Rotherham, like many other towns and cities in Britain, is also faced with external threats which can exacerbate internal challenges. An example of this is how recognition of the involvement of some men of Asian Pakistani heritage, in the abuse of children in Rotherham, led some political groups to capitalise on fears. However, it is clear that children are best protected in resilient families and communities. Thankfully, Rotherham and its people continue to demonstrate resilience. In addition, there is also a strong sense of realism, no-one in Rotherham expects perfection, but they do expect to do everything possible to protect children and young people. One woman made the distinction between surviving and thriving: “
I don’t want to survive, I want to thrive
” We hope this report contributes to that aim and welcome your views on the findings from data collected between April and June 2015. We recognise that the data is reflective of views expressed at that time and that RMBC and the people of Rotherham, have continued to respond to needs throughout the course of this analysis process

    Pamela: development of the RF system for a non-relativistic non-scaling FFAG

    Get PDF
    The PAMELA project(Particle Accelerator For MEdical Applications) currently consists of the design of a particle therapy facility. The project, which is in the design phase, contains Non-Scaling FFAG, particle accelerator capable of rapid beam acceleration, giving a pulse repetition rate of 1kHz, far beyond that of a conventional synchrotron. To realise the repetition rate, a key component of the accelerator is the rf accelerating system. The combination of a high energy gain per turn and a high repetition rate is a significant challenge. In this paper, options for the rf system of the proton ring and the status of development are presented

    The scattering of muons in low Z materials

    Full text link
    This paper presents the measurement of the scattering of 172 MeV/c muons in assorted materials, including liquid hydrogen, motivated by the need to understand ionisation cooling for muon acceleration. Data are compared with predictions from the Geant 4 simulation code and this simulation is used to deconvolute detector effects. The scattering distributions obtained are compared with the Moliere theory of multiple scattering and, in the case of liquid hydrogen, with ELMS. With the exception of ELMS, none of the models are found to provide a good description of the data. The results suggest that ionisation cooling will work better than would be predicted by Geant 4.7.0p01.Comment: pdfeTeX V 3.141592-1.21a-2.2, 30 pages with 22 figure

    Solar Carbon Monoxide, Thermal Profiling, and the Abundances of C, O, and their Isotopes

    Get PDF
    A solar photospheric "thermal profiling" analysis is presented, exploiting the infrared rovibrational bands of carbon monoxide (CO) as observed with the McMath-Pierce Fourier transform spectrometer (FTS) at Kitt Peak, and from above the Earth's atmosphere by the Shuttle-borne ATMOS experiment. Visible continuum intensities and center-limb behavior constrained the temperature profile of the deep photosphere, while CO center-limb behavior defined the thermal structure at higher altitudes. The oxygen abundance was self consistently determined from weak CO absorptions. Our analysis was meant to complement recent studies based on 3-D convection models which, among other things, have revised the historical solar oxygen (and carbon) abundance downward by a factor of nearly two; although in fact our conclusions do not support such a revision. Based on various considerations, an oxygen abundance of 700+/-100 ppm (parts per million relative to hydrogen) is recommended; the large uncertainty reflects the model sensitivity of CO. New solar isotopic ratios also are reported for 13C, 17O, and 18O.Comment: 90 pages, 19 figures (some with parts "a", "b", etc.); to be published in the Astrophysical Journal Supplement

    Vortex Dynamics in Dissipative Systems

    Full text link
    We derive the exact equation of motion for a vortex in two- and three- dimensional non-relativistic systems governed by the Ginzburg-Landau equation with complex coefficients. The velocity is given in terms of local gradients of the magnitude and phase of the complex field and is exact also for arbitrarily small inter-vortex distances. The results for vortices in a superfluid or a superconductor are recovered.Comment: revtex, 5 pages, 1 encapsulated postscript figure (included), uses aps.sty, epsf.te

    Conceptual design of a nonscaling fixed field alternating gradient accelerator for protons and carbon ions for charged particle therapy

    Get PDF
    Published by the American Physical Society under the terms of the Creative Commons Attribution 3.0 License. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI.The conceptual design for a nonscaling fixed field alternating gradient accelerator suitable for charged particle therapy (the use of protons and other light ions to treat some forms of cancer) is described.EPSR

    Improving Predictions for Helium Emission Lines

    Get PDF
    We have combined the detailed He I recombination model of Smits with the collisional transitions of Sawey & Berrington in order to produce new accurate helium emissivities that include the effects of collisional excitation from both the 2 (3)S and 2 (1) S levels. We present a grid of emissivities for a range of temperature and densities along with analytical fits and error estimates. Fits accurate to within 1% are given for the emissivities of the brightest lines over a restricted range for estimates of primordial helium abundance. We characterize the analysis uncertainties associated with uncertainties in temperature, density, fitting functions, and input atomic data. We estimate that atomic data uncertainties alone may limit abundance estimates to an accuracy of 1.5%; systematic errors may be greater than this. This analysis uncertainty must be incorporated when attempting to make high accuracy estimates of the helium abundance. For example, in recent determinations of the primordial helium abundance, uncertainties in the input atomic data have been neglected.Comment: ApJ, accepte
    • 

    corecore