PAC07 - List of Authors (Hartin, A. F.)

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Hartin, A. F.

Paper	Title	Page
MOPAN108	The FONT4 ILC Intra-train Beam-based Digital Feedback System Prototype	416
	P. Burrows, G. B. Christian, C. I. Clarke, B. Constance, A. F. Hartin, H. D. Khah, C. Perry, C. Swinson, G. R. White JAI, Oxford A. Kalinin STFC/DL/ASTeC, Daresbury, Warrington, Cheshire S. Molloy SLAC, Menlo Park, California
	We present the design of the FONT4 intra-train beam-based digital position feedback system prototype. The system incorporates a fast analogue beam position monitor front-end signal processor, a digital feedback board, and a fast kicker-driver amplifier. The system latency goal is less than 150ns. We report preliminary results of beam tests at the Accelerator Test Facility (ATF) at KEK using electron bunches separated by c. 150ns.
WEOBAB01	Electromagnetic Background Tests for the ILC Interaction Point Feedback System	1970
	P. Burrows, G. B. Christian, C. I. Clarke, B. Constance, A. F. Hartin, H. D. Khah, C. Perry, C. Swinson, G. R. White JAI, Oxford R. Arnold, S. Molloy, S. Smith, G. R. White, M. Woods SLAC, Menlo Park, California A. Kalinin STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
	We present results obtained with the T-488 experiment at SLAC Endstation A (ESA). A material model of the ILC extraction-line design was assembled and installed in ESA. The module includes materials representing the mask, beamline calorimeter, and first extraction quadrupole, encompassing a stripline interaction-point feedback system beam position monitor (BPM). The SLAC high-energy electron beam was used to irradiate the module in order to mimic the electromagnetic (EM) backgrounds expected in the ILC interaction region. The impact upon the performance of the feedback BPM was measured, and compared with detailed simulations of its expected response.
	Slides
THPMN079	Simulation of ILC Feedback BPM Signals in an Intense Background Environment	2889
	A. F. Hartin, P. Burrows, G. B. Christian, C. I. Clarke, B. Constance, H. D. Khah, C. Perry, C. Swinson, G. R. White JAI, Oxford R. Arnold, S. Molloy, S. Smith, M. Woods SLAC, Menlo Park, California A. Kalinin STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
	Funding: This work is supported in part by the Commission of the European Communities under the 6th Framework Programme "Structuring the European Research Area", contract number RIDS-011899. Experiment T-488 at SLAC, End Station A recorded distorted BPM voltage signals and an accurate simulation of these signals was performed. Geant simulations provided the energy and momentum spectrum of the incident spray and secondary emissions, and a method via image charges was used to convert particle momenta and number density into BPM stripline currents. Good agreement was achieved between simulated and measured signals. Further simulation of experiment T-488 with incident beam on axis and impinging on a thin radiator predicted minimal impact due to secondary emission. By extension to worst case conditions expected at the ILC, simulations showed that background hits on BPM striplines would have a negligible impact on the accuracy of beam position measurements and hence the operation of the FONT feedback system
THPMN080	Incoherent pair background processes with full polarizations at the ILC	2892
	A. F. Hartin JAI, Oxford
	Funding: This work is supported in part by the Commission of the European Communities under the 6th Framework Programme "Structuring the European Research Area", contract number RIDS-011899. Incoherent background pair production processes are studied with respect to full polarizations of all states. Real initial photon polarizations are obtained via a QED calculation of the beamstrahlung process. Virtual photon polarizations are related to the electric field of the colliding bunches at the point of pair production. An explicit expression for the virtual photon polarization vector is developed and found to have no circular polarization component. Pair polarization states are highly dependent on initial state circular polarization and are consequently produced almost unpolarized. The Breit-Wheeler cross-section with full polarizations is calculated and coded into the CAIN pair generator program. Numerical evaluations of the ILC operating in the seven proposed collider parameter sets shows that there are 10-20% less low energy pairs than previously thought. Collider luminosity as calculated by CAIN remains the same.
WEOCAB01	Design of the Beam Delivery System for the International Linear Collider	1985
	A. Seryi, J. A. Amann, R. Arnold, F. Asiri, K. L.F. Bane, P. Bellomo, E. Doyle, A. F. Fasso, L. Keller, J. Kim, K. Ko, Z. Li, T. W. Markiewicz, T. V.M. Maruyama, K. C. Moffeit, S. Molloy, Y. Nosochkov, N. Phinney, T. O. Raubenheimer, S. Seletskiy, S. Smith, C. M. Spencer, P. Tenenbaum, D. R. Walz, G. R. White, M. Woodley, M. Woods, L. Xiao SLAC, Menlo Park, California I. V. Agapov, G. A. Blair, S. T. Boogert, J. Carter Royal Holloway, University of London, Surrey M. Alabau, P. Bambade, J. Brossard, O. Dadoun LAL, Orsay M. Anerella, A. K. Jain, A. Marone, B. Parker BNL, Upton, Long Island, New York D. A.-K. Angal-Kalinin, C. D. Beard, J.-L. Fernandez-Hernando, P. Goudket, F. Jackson, J. K. Jones, A. Kalinin, P. A. McIntosh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire R. Appleby UMAN, Manchester J. L. Baldy, D. Schulte CERN, Geneva L. Bellantoni, A. I. Drozhdin, V. S. Kashikhin, V. Kuchler, T. Lackowski, N. V. Mokhov, N. Nakao, T. Peterson, M. C. Ross, S. I. Striganov, J. C. Tompkins, M. Wendt, X. Yang Fermilab, Batavia, Illinois K. Buesser DESY, Hamburg P. Burrows, G. B. Christian, C. I. Clarke, A. F. Hartin OXFORDphysics, Oxford, Oxon G. Burt, A. C. Dexter Cockcroft Institute, Warrington, Cheshire J. Carwardine, C. W. Saunders ANL, Argonne, Illinois B. Constance, H. Dabiri Khah, C. Perry, C. Swinson JAI, Oxford O. Delferriere, O. Napoly, J. Payet, D. Uriot CEA, Gif-sur-Yvette C. J. Densham, R. J.S. Greenhalgh STFC/RAL, Chilton, Didcot, Oxon A. Enomoto, S. Kuroda, T. Okugi, T. Sanami, Y. Suetsugu, T. Tauchi KEK, Ibaraki A. Ferrari UU/ISV, Uppsala J. Gronberg LLNL, Livermore, California Y. Iwashita Kyoto ICR, Uji, Kyoto W. Lohmann DESY Zeuthen, Zeuthen L. Ma STFC/DL, Daresbury, Warrington, Cheshire T. M. Mattison UBC, Vancouver, B. C. T. S. Sanuki University of Tokyo, Tokyo V. I. Telnov BINP SB RAS, Novosibirsk E. T. Torrence University of Oregon, Eugene, Oregon D. Warner Colorado University at Boulder, Boulder, Colorado N. K. Watson Birmingham University, Birmingham H. Y. Yamamoto Tohoku University, Sendai
	The beam delivery system for the linear collider focuses beams to nanometer sizes at the interaction point, collimates the beam halo to provide acceptable background in the detector and has a provision for state-of-the art beam instrumentation in order to reach the physics goals. The beam delivery system of the International Linear Collider has undergone several configuration changes recently. This paper describes the design details and status of the baseline configuration considered for the reference design.
	Slides
THPMN083	Spin Tracking at the International Linear Collider	2901
	I. R. Bailey, I. R. Bailey, J. A. Clarke, J. B. Dainton, L. J. Jenner, O. B. Malyshev, L. I. Malysheva, G. A. Moortgat-Pick, D. J. Scott Cockcroft Institute, Warrington, Cheshire D. P. Barber DESY, Hamburg E. Baynham, T. W. Bradshaw, F. S. Carr, Y. Ivanyushenkov, J. Rochford STFC/RAL/ASTeC, Chilton, Didcot, Oxon A. Birch STFC/DL/ASTeC, Daresbury, Warrington, Cheshire A. J. Brummitt, A. J. Lintern STFC/RAL, Chilton, Didcot, Oxon P. Cooke, L. Zang Liverpool University, Science Faculty, Liverpool A. F. Hartin OXFORDphysics, Oxford, Oxon
	Funding: This work is supported in part by the Commission of the European Communities under the 6th Framework Programme "Structuring the European Research Area", contract number RIDS-011899. Polarized electron and positron beams are foreseen for the future International Linear Collider (ILC), with polarized electrons already included in the baseline design and polarized positrons seen as a highly-desirable upgrade. High precision physics requires the polarization of both beams to be known with a relative uncertainty of approximately 0.5% or better. Therefore all possible depolarization effects that could operate between the polarized sources and the interaction regions have to be carefully modelled. The "heLiCal" collaboration aims to provide a full "cradle-to-grave" analysis of all depolarization effects at the ILC, and to develop software tools to carry out appropriate computer simulations. In this paper we report on the first phase of our work which includes extensive simulations of the ILC spin-dynamics and a detailed study of beam-beam depolarization effects at the interaction point(s).