• R. Kersevan, M. Hahn, I. Parat, D. Schmied
  ESRF, Grenoble

This paper outlines the present status and configuration of the ESRF vacuum system and its performance over the last years. A short overview of the installed vacuum devices is given as well as an outlook of future developments towards the planned ESRF upgrade. The storage ring down times caused by vacuum accidents have been dramatically improved due to a systematical survey using advanced vacuum diagnostic tools. Their use and drawbacks will also be discussed in this paper.

• Y. Wang, L. Fan, L. Liu, J. P. Wang, W. Wei, B. Zhang
  USTC/NSRL, Hefei, Anhui
• Y.F. Zhang
  IHEP Beijing, Beijing

TiN coating has been widely applied in surface treatments of particle accelerator vacuum chambers because of its characteristics such as good electrical conductivity, stability of performance, ability to block hydrogen permeation, low SEY, etc. With DC sputtering, TiN film has been coated on the inner face of a stainless steel pipe vacuum chamber, 86 mm in diameter and 2300 mm in length. The vacuum performances testing of the coated chamber has also been done, including thermal outgassing rate measurement, PSD measurement, and SEY measurement of samples. Compared with those of uncoated stainless steel chamber, the results show that coating TiN film is a very effective method of the treatment of particle accelerator vacuum chamber.

• S. Lederer, S. Schreiber
  DESY, Hamburg
• P.M. Michelato, L. Monaco, C. Pagani, D. Sertore
  INFN/LASA, Segrate (MI)
• R. Ovsyannikov, M. Sperling, A. Vollmer
  BESSY GmbH, Berlin
• F. Stephan
  DESY Zeuthen, Zeuthen

Caesium telluride (Cs2Te) photocathodes are used as sources for electron beams because of their high quantum efficiency (QE) and their ability to release high peak current electron bunches in a high gradient RF-gun. A rapid unexpected decrease of the initial QE, from 10% to values below 0.5% in only a few weeks of operation, was observed. In XPS measurements we identify a peak of Fluorine possibly originating from Teflon. After identification and removal of this specific contaminant, the life time of the cathodes increased to several months. In addition we have investigated the response of fully functional photocathodes to extensive usage, bad vacuum conditions, and oxidation by means of XPS measurements. The experiments - carried out at the ISISS and the PM3 beam lines at the synchrotron facility BESSY – compare the chemical composition and electronic structure of freshly prepared, contaminated, used, and oxidised Cs2Te cathodes.

• L. Hagge, N. Bergel, A. Herz, J. Kreutzkamp, S. Sühl, N. Welle
  DESY, Hamburg

In most sub-systems of the European XFEL, more than one institute participates in the design & development activities. This is the case for e.g. the cold linac, cryogenics, bunch compressors, undulators and photon beam systems. To ensure interface compatibility and make sure components fit into their complex environments, the collaborating institutes have to create high-level 3D models of their sub-systems. These 3D models are centrally integrated into a master model, which enables identification and elimination of collisions and non-conformities prior to manufacturing. A "collaborative design process", which supports efficient, interactive and inter-disciplinary cooperation of different institutes, has been successfully developed and established at the European XFEL. It consists of design guidelines and processes definitions for information & data exchange, reviews, approvals and change management. The process is supported by the DESY Engineering Data Management System, DESY EDMS, and allows the combination of 3D models from multiple 3D CAD systems. Following the good experience at the European XFEL, the same process is now established at the Global Design Effort for the ILC.

• K. Kershaw, C. Bertone, P. Bestmann, T. Feniet, D. Forkel-Wirth, J.L. Grenard, N. Rousset
  CERN, Geneva

Personnel access to the LHC tunnel will be restricted to varying extents during the life of the machine due to radiation and cryogenic hazards. For this reason a remotely operated modular inspection train, (TIM) running on the LHC tunnel’s overhead monorail has been developed. In order to be compatible with the LHC personnel access system, a small section train that can pass through small openings at the top of sector doors has now been produced. The basic train can be used for remote visual inspection; additional modules give the capability of carrying out remote measurement of radiation levels, environmental conditions around the tunnel, and even remote measurement of the precise position of machine elements such as collimators. The paper outlines the design, development and operation of the equipment including preparation of the infrastructure. Key features of the trains are described along with future developments and intervention scenarios.

• T. Touzé, H. Mainaud Durand, D.P. Missiaen
  CERN, Geneva

The CLIC components will have to be pre-aligned within a tolerance of 10 microns over a sliding window of 200m all along the linacs, before injecting the first beam. Such tolerance is about 30 times more demanding than for the existing machines as the SPS and LHC; it is a technical challenge and a key issue for the CLIC feasibility. In order to define the CLIC alignment strategy from the survey and beam dynamics point of view, simulations have been undertaken concerning the propagation error due to the measurement uncertainties of the pre-alignment systems. The uncertainties of measurement, taken as hypotheses for the simulations, are based on the data obtained on several dedicated facilities. This paper introduces the facilities and the latest results obtained, as well as the simulations performed.

• M. Masuzawa, Y. Ohsawa, N. Ohuchi
  KEK, Ibaraki

KEKB is a double-ring collider with a circumference of 3016 m. The two rings were built side-by-side in the TRISTAN tunnel, 11 m below ground. KEKB has been operating successfully for about 10 years, since 1999, and its peak luminosity continues to improve. During the summer shutdown of 2008, the magnet tilts were measured for the first time since installation and it was found that some magnets were rotated over time. The tunnel level marker and the magnet height were also surveyed. The south region of the tunnel is sinking, resulting in magnet level changes. The survey results will be reported in this paper.

• W.Y. Lai, J.-R. Chen, T.C. Tseng, H.S. Wang
  NSRRC, Hsinchu

TPS (Taiwan Photon Source) is a new 3GeV ring to be constructed at NSRRC Taiwan. A motorized magnet girder system with 6 cam movers on 3 pedestals had been designed and tested to provide 6-axis precise adjustments. With 3 consecutive girders to form one section, there will be 72 girders in the whole ring. In order to align the girders precisely and quickly with less manpower, considering the deformation of the floor and limited space in the tunnel also frequent earthquakes in Taiwan, a whole-ring girders auto alignment system was thus proposed. This system consists of touched sensors between consecutive girders and laser PSD system between straight section girders in addition with electric leveling sensors on each girder. The system operating algorithm had been defined and program also fulfilled to be tested on a 3 girders prototype system. The detailed system design and testing results would be described in this paper.

• A. Reichold, C. Uribe Estrada, D. Urner, S.Q. Yang
  OXFORDphysics, Oxford, Oxon
• P.J. Brockill, J. Dale, M. Jones, G.R. Moss, R. Wastie
  JAI, Oxford
• M. Schlösser
  DESY, Hamburg

Funding: work supported by STFC in the LC-ABD collaboration and by the Commission of the European Community, 6th Framework Programme, Structuring the European Research Area, contract number RIDS-011899

The Linear Collider Alignment and Survey group has completed experiments with a prototype robotic survey train for the ILC called the RTRS (Rapid Tunnel Reference Surveyor). Calibration of the RTRS is the most difficult part of data analysis, involving advanced mathematical methods to obtain constraint independent calibration parameters and errors. We show how sub-system data analysis provides input errors for the calibration process. We present the mathematical formalism used and results from the calibration of one of the three cars.