Reception Test of Petals for the End Cap TEC+ of the CMS Silicon Strip Tracker

The silicon strip tracker of the CMS experiment has been completed and was inserted into the CMS detector in late 2007. The largest sub system of the tracker are its end caps, comprising two large end caps (TEC) each containing 3200 silicon strip modules. To ease construction, the end caps feature a modular design: groups of about 20 silicon modules are placed on sub-assemblies called petals and these self-contained elements are then mounted onto the TEC support structures. Each end cap consists of 144 such petals, which were built and fully qualified by several institutes across Europe. Fro

Integration of the End Cap TEC+ of the CMS Silicon Strip Tracker

The silicon strip tracker of the CMS experiment has been completed and inserted into the CMS detector in late 2007. The largest sub-system of the tracker is its end cap system, comprising two large end caps (TEC) each containing 3200 silicon strip modules. To ease construction, the end caps feature a modular design: groups of about 20 silicon modules are placed on sub-assemblies called petals and these self-contained elements are then mounted into the TEC support structures. Each end cap consists of 144 petals, and the insertion of these petals into the end cap structure is referred to as TEC integration. The two end caps were integrated independently in Aachen (TEC+) and at CERN (TEC--). This note deals with the integration of TEC+, describing procedures for end cap integration and for quality control during testing of integrated sections of the end cap and presenting results from the testing

Energy Resolution Performance of the CMS Electromagnetic Calorimeter

The energy resolution performance of the CMS lead tungstate crystal electromagnetic calorimeter is presented. Measurements were made with an electron beam using a fully equipped supermodule of the calorimeter barrel. Results are given both for electrons incident on the centre of crystals and for electrons distributed uniformly over the calorimeter surface. The electron energy is reconstructed in matrices of 3 times 3 or 5 times 5 crystals centred on the crystal containing the maximum energy. Corrections for variations in the shower containment are applied in the case of uniform incidence. The resolution measured is consistent with the design goals

Preliminary Irradiation Tests Of The Apvd Circuit For The

The APVD circuit, developed in the 0.8 radiation hard SOI DMILL technology [2][3][4] from ATMEL/TEMIC-MHS Nantes, for the front end electronic of the CMS tracker, has been irradiated at CERN using a 10KeV Xray beam up to a total dose of 20Mrad. The main performances of the APVD like gain, pulse shape, noise are presented as a function of the radiation dose. In particular the cause of the DAC non linearity in the bias generator part is discussed

Data Acquisition Board for a Beam-Tagging Hodoscope Used in Hadrontherapy Monitoring

International audienceThere have been suggested methods to implement real-time ion-range monitoring for quality assurance in hadrontherapy. Prompt gamma (PG) detection is a promising technique and several prototypes using various modalities are under developments worldwide. Some systems use time-of-flight (TOF) measurements to discriminate PG from the neutron background (e.g. TOF PG cameras), while others employ Prompt Gamma Timing approach for indirect measurement of ion range. All require precise measurement of arrival time of incident ions detected by a beam-tagging hodoscope. One type of such hodoscopes for this purpose has been developed by CLaRyS collaboration network (consisting of several IN2P3 laboratories). It consists of an array of scintillating fibers in vertical and horizontal directions. The optical fibers are coupled to multi-anode photomultipliers.We report here the development of a data acquisition (DAQ) board to be associated with a scintillating-fiber-based hodoscope. The board incorporates two 32-channel readout ASICs, a FPGA (StratixII GX EP2SGX30C/D) and an optical transceiver (enhanced small form-factor pluggable transceiver). Each readout ASIC also integrates a time-to-digital converter (TDC) and a multiplexed analog output for monitoring of scintillating fibers ageing. The FPGA performs data processing, transmission and slow control. The transceiver performs electrical-and-optical-signal conversion and bidirectional transmission at 3 Gbit/s rate. Via an optical fiber, the board can be connected to a μTCA-based data acquisition system. The board also include a clock jitter cleaner (LMK04828) to generate several clock signals from an external reference clock. The board supports two types of triggers: a self-trigger for stand-alone tests and an external trigger for coupling with imaging systems like prompt gamma cameras. In order to optimize data throughput, the transceiver uses only basic 8-/10-bit protocol and fully exploits specific control symbols to distinguish different types of frames (control, monitoring, and data).The board was designed to meet the system requirements: 1-mm spatial resolution, 1-ns timing resolution, and 100-MHz counting rate capability. To ensure time-measuring precision and transmission reliability, phase determination and frequency synchronization techniques were implemented. The board was fabricated and its operation was verified by test benches. Beam tests (with hodoscope and acquisition system) have been scheduled and are being prepared

Characterization of a beam-tagging hodoscope for hadrontherapy monitoring

International audienceA beam tagging hodoscope prototype made of squared 1 mm2 fibers arranged in two perpendicular planes and coupled to multi-anode photomultipliers has been studied using 65 MeV proton as well as 95 MeV/u 12C beams at various intensities. This hodoscope successfully provided 2D images of proton beams with a detection efficiency larger than 98% with logical OR condition between the two fiber planes. The detection efficiency with a coincidence between the two planes is close to 75% for beam intensities up to ~1 MHz. Moreover, the timing resolution is around 1.8 ns FWHM. Overall, the performances show that such a technology is viable for beam monitoring during hadrontherapy

Etiquetage spatio-temporel et monitorage de faisceaux pulsés : applications en hadronthérapieet thérapies « flash »

National audienc

Petal Integration for the CMS Tracker End Caps

This note describes the assembly and testing of the 292 petals built for the CMS Tracker End Caps from the beginning of 2005 until the summer of 2006. Due to the large number of petals to be assembled and the need to reach a throughput of 10 to 15 petals per week, a distributed integration approach was chosen. This integration was carried out by the following institutes: I. and III. Physikalisches Institut - RWTH Aachen University; IIHE, ULB \& VUB Universities, Brussels; Hamburg University; IEKP, Karlsruhe University; FYNU, Louvain University; IPN, Lyon University; and IPHC, Strasbourg University. Despite the large number of petals which needed to be reworked to cope with a late-discovered module issue, the quality of the petals is excellent with less than 0.2\% bad channels

Energy Resolution of the Barrel of the CMS Electromagnetic Calorimeter

The energy resolution of the barrel part of the CMS Electromagnetic Calorimeter has been studied using electrons of 20 to 250 GeV in a test beam. The incident electron's energy was reconstructed by summing the energy measured in arrays of 3x3 or 5x5 channels. There was no significant amount of correlated noise observed within these arrays. For electrons incident at the centre of the studied 3x3 arrays of crystals, the mean stochastic term was measured to be 2.8% and the mean constant term to be 0.3%. The amount of the incident electron's energy which is contained within the array depends on its position of incidence. The variation of the containment with position is corrected for using the distribution of the measured energy within the array. For uniform illumination of a crystal with 120 GeV electrons a resolution of 0.5% was achieved. The energy resolution meets the design goal for the detector

Results of the first performance tests of the CMS electromagnetic calorimeter

CMS ECALPerformance tests of some aspects of the CMS ECAL were carried out on modules of the "barrel" sub-system in 2002 and 2003. A brief test with high energy electron beams was made in late 2003 to validate prototypes of the new Very Front End electronics. The final versions of the monitoring and cooling systems, and of the high and low voltage regulation were used in these tests. The results are consistent with the performance targets including those for noise and overall energy resolution, required to fulfil the physics programme of CMS at the LHC