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We present a detailed design for the upgrade of the analog front-end electronics for the ATLAS Tile Calorimeter (TileCal) at the sLHC by using the latest deep-micron-technology based, commercial off-the-shelf (COTS) components. We believe that with the latest technology based analog devices, the significant improvements in radiation tolerance are possible. The front-end analog electronics presents a 17-bit dynamic range in readout of PMT signals. The PMT output signal is processed with a 7-pole passive LC shaper, followed by a pair of bi-gain amplifiers and two 40Msps sampling ADCs. The readout system is capable of measuring energy deposition in a single calorimeter cell from ∼220MeV to 1.3TeV with full digital Level-1 trigger capability for the ATLAS experiment at the sLHC. The other on-board features include slow current integrator used for detector calibration with cesium source to normalize the PMT gains and the charge injection for calibrating linearity and dynamic range for the readout electronics. A total of ∼10,000 channels of readout electronics are needed in the upgrade to replace the current system at the LHC.

Micro-Channel Plate devices (MCP) provide fast signals with rise-times in the 100 ps range, allowing a measurement of the time-of-arrival of light pulses with a few pico-seconds accuracy using either constant fraction discrimination followed by time-to-digital conversion, or waveform sampling processed after digitization. The coupling of the MCP anode plane to 50 Ω transmission lines allows both a precise time measurement and additionally the potential for a position measurement with an accuracy of a few hundred microns for large-area devices. We present position measurement results obtained with MCPs from Photonis, 10-cm transmission lines, and a calibrated laser source followed by sampling and digitization, and waveform analysis. A detailed simulation of the transmission lines is presented. We compare the measured position resolution for two identical setups but with MCPs of different pore diameters: 25 and 10 microns. Simulation results are also presented for transmission lines up to 1-m in length.

The measurement of time-of-flight (TOF) of relativistic particles in high-energy colliders with picosecond resolution would qualitatively change the ability to identify underlying parton-level processes at future colliders or upgrades of existing detectors. We have measured the timing properties of three micro-channel plate photo-multiplier tubes (MCPPMTs) from Photonis; one with 1024 anodes and the other two with 64 anodes. The 1024-anode 10-micron pore tube uses a charge-collection scheme at the anode to provide equal arrival time of the signal independent of the hit position of incident light on the face of the tube. The two 64-anode 25-micron pore tubes have a commercially available collection scheme and were used to find a limit on the timing resolution. We have performed these measurements using a newly assembled test-stand based on a Hamamatsu PLP-10 picosecond laser and a commercial CAMAC readout electronics system. We present these results and compare timing properties to earlier versions of the charge collection scheme.