Investigations of Slow Motions of the SLAC Linac Tunnel

Investigations of slow transverse motion of the linac tunnel of the Stanford Linear Collider have been performed over period of about one month in December 1999 -- January 2000. The linac laser alignment system, equipped with a quadrant photodetector, allowed submicron resolution measurement of the motion of the middle of the linac tunnel with respect to its ends. Measurements revealed two major sources responsible for the observed relative motion. Variation of the external atmospheric pressure was found to be the most significant cause of short wavelength transverse motion of the tunnel. The long wavelength component of the motion has been also observed to have a large contribution from tidal effects. The measured data are essential for determination of parameters for the Next Linear Collider.Comment: Submitted to XX International Linac Conferenc

Ground Motion Model of the SLAC Site

We present a ground motion model for the SLAC site. This model is based on recent ground motion studies performed at SLAC as well as on historical data. The model includes wave-like, diffusive and systematic types of motion. An attempt is made to relate measurable secondary properties of the ground motion with more basic characteristics such as the layered geological structure of the surrounding earth, depth of the tunnel, etc. This model is an essential step in evaluating sites for a future linear collider.Comment: submitted to XX International Linac Conferenc

A Shaky Road to Subnanometer Beams. NLC Ground Motion, Vibration and Stabilization Studies

Ground motion and vibration can be a limiting factor in the performance of future linear colliders. Investigations of ground motion have been carried out around the world for several decades. In this review, results of recent investigations of ground motion as well as ongoing developments of stabilization methods are presented.Comment: Invited talk given at the 18th International Conference On High Energy Accelerators (HEACC 2001) 26-30 Mar 2001, Tsukuba, Japa

Unifying Physics of Accelerators, Lasers and Plasma

Unifying Physics of Accelerators, Lasers and Plasma introduces the physics of accelerators, lasers and plasma in tandem with the industrial methodology of inventiveness, a technique that teaches that similar problems and solutions appear again and again in seemingly dissimilar disciplines. This unique approach builds bridges and enhances connectio

Educating and Training Accelerator Scientists and Technologists for Tomorrow

Accelerator science and technology is inherently an integrative discipline that combines aspects of physics, computational science, electrical and mechanical engineering. As few universities offer full academic programs, the education of accelerator physicists and engineers for the future has primarily relied on a combination of on-the-job training supplemented with intense courses at regional accelerator schools. This paper describes the approaches being used to satisfy the educational interests of a growing number of interested physicists and engineers.Comment: 19 pages, 3 figure

New Developments in Linear Colliders Final Focus Systems

The length, complexity and cost of the present Final Focus designs for linear colliders grows very quickly with the beam energy. In the letter, a novel final focus system is presented and compared with the one proposed for NLC. This new design is simpler, shorter and cheaper, with comparable bandwidth, tolerances and tunability. Moreover, the length scales slower than linearly with energy allowing for a more flexible design which is applicable over a much larger energy range

GigaGauss solenoidal magnetic field inside of bubbles excited in under-dense plasma

Magnetic fields have a crucial role in physics at all scales, from astrophysics to nanoscale phenomena. Large fields, constant or pulsed, allow investigation of material in extreme conditions, opening up plethora of practical applications based on ultra-fast process, and studying phenomena existing only in exotic astro-objects like neutron stars or pulsars. Magnetic fields are indispensable in particle accelerators, for guiding the relativistic particles along a curved trajectory and for making them radiate in synchrotron light sources and in free electron lasers. In the presented paper we propose a novel and effective method for generating solenoidal quasi-static magnetic field on the GigaGauss level and beyond, in under-dense plasma, using screw-shaped high intensity laser pulses. In comparison with already known techniques which typically rely on interaction with over-dense or solid targets, where radial or toroidal magnetic field localized at the stationary target were generated, our method allows to produce gigantic solenoidal fields, which is co-moving with the driving laser pulse and collinear with accelerated electrons. The solenoidal field is quasi-stationary in the reference frame of the laser pulse and can be used for guiding electron beams and providing synchrotron radiation beam emittance cooling for laser-plasma accelerated electron and positron beams, opening up novel opportunities for designs of the light sources, free electron lasers, and high energy colliders based on laser plasma acceleration.Comment: 15 pages, 9 figures. Main text (without abstract, References and Appendix): 12 page

The ILC Beam Delivery System - Conceptual Design and RD Plans

The Beam Delivery System of the ILC has many stringent and sometimes conflicting requirements. To produce luminosity, the beams must be focused to nanometer size. To provide acceptable detector backgrounds, particles far from the beam core must be collimated. Unique beam diagnostics and instrumentation are required to monitor parameters of the colliding beams such as the energy spectrum and polarization. The detector and beamline components must be protected against errant beams. After collision, the beams must also be transported to the beam dumps safely and with acceptable losses. An international team is actively working on the design of the ILC Beam Delivery System in close collaboration. Details of the design, recent progress and remaining challenges will be summarized in this paper