G Bowden

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  • M Woods, C Adolphsen, R Arnold, G Bowden, B Bower, R Erickson +87 others
  • 2006
The SLAC Linac can deliver to End Station A (ESA) a high-energy test beam with similar beam parameters as for the International Linear Collider (ILC) for bunch charge, bunch length and bunch energy spread.[1] ESA beam tests run parasitically with PEP-II with single damped bunches at 10Hz, beam energy of 28.5 GeV and bunch charge of (1.5-2.0)·10 10(More)
  • F Le Pimpec, S Adiga, Stanford Univ, F Asiri, G Bowden, E Doyle +2 others
  • 2002
The vibration of components of the NLC linac, such as accelerating structures and girders, is being studied both experimentally and analytically. Various effects are being considered including structural resonances and vibration caused by cooling water in the accelerating structure. This paper reports the status of ongoing work.
There are many challenges in the design of the normal-conducting portion of the ILC positron injector system such as achieving adequate cooling with the high RF and particle loss heating, and sustaining high accelerator gradients during millisecond-long pulses in a strong magnetic field. The proposed design for the positron injector contains both(More)
  • F Wang, C Adolphsen, G Bowden, C Nantista, R Swent, J Tice +4 others
  • 2007
Fundamental power couplers for superconducting accelerator applications like the ILC are complicated transmission line assemblies that must simultaneously accommodate demanding RF power, cryogenic, and cleanliness constraints. When these couplers are RF conditioned, the observed response is an aggregate of all the parts of the coupler and the specific(More)
Due to the extremely high energy deposition from positrons, electrons, photons and neutrons behind the positron target, and because a solenoid is required to focus the large emittance positron beam, the 1.3 GHz pre-accelerator has to use normal conducting structures up to energy of 400 MeV. There are many challenges in the design of the normal-conducting(More)
  • M Sullivan, G Bowden, S Ecklund, D Jensen, M Nordby, A Ringwall +1 other
  • 1997
We describe the construction of a prototype hybrid permanent magnet dipole and quadruple. The magnet consists of two concentric rings of SmzCol, magnetic material 5 cm in len&th. The outer ring is made of 16 uniformly ma&netized blocks assembled as a Halbach dipole and the inner ring has 32 blocks oriented in a similar fashion so as to &enerate a quadruple(More)
  • M Sullivan, G Bowden, H Destaebler, S Ecklund, J Hodgson, T Mattison +11 others
  • 1996
1 ABSTRACT We describe the Interaction Region (IR) for the PEP-II project[l], a collaboration of SLAC, LBNL, and LLNL. The near IR region inboard of 3 m from the interaction point (IP) is designed to focus the 3.1 GeV low-energy beam (LEB) and bring it into head-on collision with the 9 GeV high-energy beam (HEB). We describe the overall design parameters of(More)
  • V A Dolgashev, C Adolphsen, D L Burke, G Bowden, R M Jones, J Lewandowski +9 others
  • 2003
The linacs proposed for the Next Linear Collider (NLC) and Japanese Linear Col-lider (JLC) would contain several thousand X-Band accelerator structures that would operate at a loaded gradient of 50 MV/m. An extensive experimental and theoretical program is underway at SLAC, FNAL and KEK to develop structures that reliably operate at this gradient. The(More)
  • J W Wang, C Adolphsen, N Baboi, G Bowden, D L Burke, J Cornuelle +23 others
  • 2002
the 'T' structures are too small from a wakefield perspective. To achieve low group velocity with acceptable iris radii, structures with a 150 degrees phase advance per cell (H-Type) have been built. Their design is described in Section 4. Dipole wakefield suppression has been studied for these structures, as well as for SW structures, which may be a viable(More)
Retractable targets of carbon fibres with nominal diameters 30, 7 and 4.5 mi-cron have been in use at the collision point of the SLC (the SLAC Linear Collider). The target mechanism is compatible with the Mark II detector now in place at the collision point. Beam profiles are measured in horizontal and vertical axes by using magnetic dipoles to scan the(More)