No Arabic abstract
We are developing the vertex detector with a fine pixel CCD (FPCCD) for the international linear collider (ILC), whose pixel size is $5 times 5$ $mu$m$^{2}$. To evaluate the performance of the FPCCD vertex detector and optimize its design, development of the software dedicated for the FPCCD is necessary. We, therefore, started to develop the software for FPCCD. In this article, the status of the study is reported.
One of candidates for the International Linear Collider(ILC)s vertex detector is the Fine Pixel CCD (FPCCD) with a pixel size of 5 times 5 (mum^2). Sensor and readout systems are currently being studied and prototypes have been developed. In this paper we will report on the performance of latest developed readout ASIC prototype as well as the outline of the design strategy for the next ASIC prototype.
One of the major physics goals at the ILC is the precise measurement of the Higgs coupling constants to b-quarks and c-quarks. To achieve this measurement, we need a high-performance vertex detector leading to precise flavor tagging. For this purpose, we are developing the Fine Pixel CCD (FPCCD) vertex detector. In this paper, we will report on the development status of FPCCDTrackFinder, a new track finder improving tracking efficiency, especially in the low $p_t$ region, and an evaluation result of the flavor tagging performance with FPCCDTrackFinder in the FPCCD vertex detector.
In order to achieve the challenging requirements on the CLIC vertex detector, a range of technology options have been considered in recent years. One prominent idea is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel readout chips. Recent results have shown the approach to be feasible, though more detailed studies of the performance of such devices, including simulation, are required. The CLICdp collaboration has developed a number of ASICs as part of its vertex detector R&D programme, and here we present results on the performance of a CCPDv3 active sensor glued to a CLICpix readout chip. Charge collection characteristics and tracking performance have been measured over the full expected angular range of incident particles using 120 GeV/c secondary hadron beams from the CERN SPS. Single hit efficiencies have been observed above 99% in the full range of track incidence angles, down to shallow angles. The single hit resolution has also been observed to be stable over this range, with a resolution around 6 $mu$m. The measured charge collection characterstics have been compared to simulations carried out using the Sentaurus TCAD finite-element simulation package combined with circuit simulations and parametrisations of the readout chip response. The simulations have also been successfully used to reproduce electric fields, depletion depths and the current-voltage characteristics of the device, and have been further used to make predictions about future device designs.
Vertex detector cable requirements are considered within the context of the SiD concept. Cable material should be limited so that the number of radiation lengths represented is consistent with the material budget. In order to take advantage of the proposed accelerator beam structure and allow cooling by flow of dry gas, pulsed power is assumed. Potential approaches to power distribution, cable paths, and cable design for operation in a 5 T magnetic field are described.
LHCb is one of the four main experiments of the Large Hadron Collider (LHC) project, which will start at CERN in 2008. The experiment is primarily dedicated to B-Physics and hence requires precise vertex reconstruction. The silicon vertex locator (VELO) has a single hit precision of better than 10 micron and is used both off-line and in the trigger. These requirements place strict constraints on its alignment. Additional challenges for the alignment arise from the detector being retracted between each fill of the LHC and from its unique circular disc r/phi strip geometry. This paper describes the track based software alignment procedure developed for the VELO. The procedure is primarily based on a non-iterative method using a matrix inversion technique. The procedure is demonstrated with simulated events to be fast, robust and to achieve a suitable alignment precision.