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Project Title: Analysis of LHCb trigger via visual inspection Student: Jamie Tattersall Outline: Develop a system that will trigger on as many b-quark events as possible whilst reducing the recorded event rate from ~ 10MHz to ~ 2KHz. A LHCb reconstructed MC event viewed in Panoramix. A LHCb reconstructed MC event in VELO with two collision vertices. L0 Trigger (hardware): • Selects events that contain high pT particles. • Reduces the event rate from 10MHz to 1Mhz. • Processing time of 4µs. Outline: Develop firmware for the control of power supplies to calorimeter detectors using a radiation hard FPGA chip. Detector Section: LHCb event filter farm Project Title: Acquisition of rack cooling equipment fans with ELMB and PVSS Student: Jonás Arroyo Relevant Technologies : Outline: • Embedded Local Monitor Board - ELMB128. Acquisition of rack cooling fans, from the LHCb • Controller Area Network bus - CAN bus. event filter. Design the signal acquisition using the • LabView. ELMB and linked to the control system and the • Frequency to Voltage Converter. PVSS scada. • PVSS SCADA – PVSS Supervisory Control And Data Acquisition. Main Challenges: • Acquire the 64 fan signals and capture them with the 4 differential 16 channels ADC (each with 16 bits) in the ELMB. • Configure the CANopen OPC Server in the PC to connect the ELMB with the PCIcan-Q card. • Test the server and the capture signals using LabView. • Connect the CANopen OPC Server in the PC to the Control System and the PVSS scada. Relevant Technologies: Field Programmable Gate Arrays – FPGA Cockcroft Walton Voltage Converters – CW bases Results: •39 point baseline characterisation of ideal CW base performance •Fault identification in 50 defective CW bases •>45 repaired CW bases successfully passed test bench, ready for installation •Synthesisable single HV channel implementation for FPGA L1 Trigger (software): • Partially reconstructs events using VELO (VErtex LOcater), TT (Trigger Tracker) and L0 information. • Selects tracks that have a high IP and pT. • Reduces event rate to 40kHz. • Processing time of ~ 1ms. Test Point Comparison 20 0 Voltage (V) -20 -40 -60 -80 -100 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 Point Number Detector Section: RICH 2 Project Title: Mirror Alignment Student: Janneke Blokland Purpose: To measure and analyse the light yield from the phototube calibration fibres to ensure their functionality. Summer Students 2005 The Calorimeter Outline: The RICH2 is designed to give a positive kaon identification for particles with momentum between 15 and 100 GeV/c. To achieve this the mirrors which focus and guide the Cherenkov light have to be aligned with high accuracy. Main Challenges: •Alignment of the spherical mirrors. •Monitoring the alignment and analyse the data. The data, with cutoff marked Results: • A profound analysis to provide a basis upon which acquisition decisions can be taken with regard to the configuration of hardware and software for the LHCb farm. • Improved characterisation of used components. • Predictions of final performance for the complete setup. Picture of the spherical mirror in the flat mirrors Source The light of the source is reflected by the spherical mirror. The position of the light with respect to the target is a measure for the position of the mirror. Mirror Main Challenges: Detector Section: LHCb Trigger Systems • Conceive test schemes to make LHCb Data Acquisition (DAQ) relevant measurements Project Title: GigaEthernet Analysis • Provide solid understanding of the Student: Cedric Walravens various factors at play on a commodity platform. • If possible, make adjustments to the Outline: current setup to improve network Analyse LHCb’s currently available performance commodity server farm, in order to locate both software and hardware bottlenecks. Results: •Less than 1% of fibres have some sort of problem •For 90% of these fibres, the problem is fixable •As of 28 July, measurement and troubleshooting 67% (or 3994 fibres) completed. 1198 296 147 40 HLT Trigger (software): • Inclusive selections for calibration and systematic errors. • Exclusive selections of important channels. • Full reconstruction of event. • Reduces event rate to ~ 2kHz. • Processing time of ~ 10ms. Causes of “Bad” Fibres: •Fibre itself is damaged •Connection to ECAL is bad •Fibre inside ECAL is damaged •Misaligned optics in the ECAL module •Missing optics in the ECAL module Base Number (Control Voltage 0.19V) Detector Section: Electromagnetic Calorimeter Project Title: Quality Control of the Electromagnetic Calorimeter (ECAL) Calibration Fibres Student: Abigail Kaboth Method: •Each of the 5952 fibres is measured individually using a pin diode •The fibres are of varying length and so must be normalized for analysis •After the fibres are normalized to a mean of 2.5 (in arbitrary units), any fibre under 1.25 (50% of the mean) is considered “bad” and investigated to find the cause Main Challenges: •Implementation of sequential set-up for 200 independent power supply channels, using 12-bit Digital-to-Analogue converters. •Test bench construction to evaluate the effectiveness of hardware implementation. •Repair and testing of defective High Voltage supply modules. Target Left mirror positions 50 Deviation from target (μrad) Challenge: • The trigger has to quickly and efficiently select interesting b-quark events. • Calibration events are needed to resolve the biases caused by the trigger algorithms. • The trigger has to have a small calculation time, ~ 10ms because of limited computational facilities. LHCb Summer Student Projects Detector Section: Hadron Calorimeter Project Title: Power Supply Control Student: James Devine Installation scaffolding and flat panels Error ± 10 μrad 30 10 x -10 y -30 -50 1 week Day/night cycle -70 5/18/05 5/25/05 6/1/05 6/8/05 6/15/05 6/22/05 Time Data of the position of the left spherical mirror taken with laser and CCD-camera. 6/29/05 7/6/05 Picture of the light spot taken with the CCD-camera.