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The CERN Large Hadron Collider (LHC) will collide two counter rotating proton beams. The energy stored in each beam is about 350 MJ. If there is a failure in an element of the accelerator, the resulting beam losses could cause damage not only to the accelerator itself, but also to the physics experiments installed. Within the Compact Muon Solenoid experiment (CMS), the use of a Beam Condition Monitor (BCM) is planned to monitor a possible fast increase of the particle flux near the interaction point. The system will flag the onset of adverse beam conditions within the CMS experiment, and, if necessary, input into the beam abort system of the LHC requesting a fast beam dump. Constraints on BCM design from radiation hardness, a minimal material and services budget, and the need for fast signals from sensors with high sensitivity and a large dynamic range, have led to the investigation of synthetic chemical vapor deposited (CVD) diamond for the BCM sensor. In a 5 GeV hadron beam the response of CVD diamonds was tested in fluxes ranging from single minimium ionizing particles (MIPs) to 108 MIPs per [cm.sup.2], delivered over 40 ns. The signal response, linearity, and stability of both un-irradiated and irradiated sensors were tested over this flux range, and will be presented herein. The results confirm the applicability of CVD diamond for this beam monitoring application. Index Terms--Beam abort, chemical vapor deposition diamond, position sensitive detectors, radiation detection: radiation detectors, semiconductor detectors: characterization.

Every position-sensitive wire detector needs to solve the problem of wire positioning with a defined accuracy all over its sensitive volume. In particular, thin-walled drift tubes ('straws'), which are currently being attached to large detector units of several tens of square meters of surface, need to be equipped with wire locators along their signal wires. A wire locator has been developed together with an insertion device, especially for medium-sized drift tube systems, which significantly reduces the production time and avoids the danger of applying epoxy glue to the signal wire. The wire locator is being inserted in one single time-saving production step together with the signal wire itself. The proposed design is being compared to the rigid wire locators in use in the COMPASS straw tracking system at CERN. The investigation comprises both wire-centering capability and influence on the efficiency of adjacent detector regions, demonstrating the competitive performance of the proposed new system. Its sufficient mechanical reliability could be shown by means of an X-ray tomography; the attractively small influence on the drift field was determined in a test measurement using a silicon tracking system in a hadron beam. Index Terms--Drift tube, straw detector, wire locator.