Abstract
To build silicon trackers of modern and future high-luminosity collider experiments, thousands of silicon strip modules have to be produced and tested. The modules in new trackers must ...reliably work usually during 5–10 years or more under harsh irradiation conditions, as it will be impossible to replace a failing module once installed inside the detector. It means that reliable and rigorous testing of strip modules and its components is mandatory. To sustain the production throughput we should be able to test several modules in parallel. For this reason a fast, reliable, scalable and cost effective production QC test bench has to be designed and implemented. For the
CV
and
IV
measurements of sensors and modules we are developing a low-cost (less than 500 €) integrated electronic board which will be scaled up to ten channels to measure DUTs in parallel. In the current work the design of the
IV
/
CV
board and the calibration procedure to increase the accuracy of the current and capacitance measurements, for which a special calibration dipole board based on tight tolerance capacitors and resistors has been designed, as well as future development plans are described.
Vertex reconstruction in CMS Chabanat, E.; D’Hondt, J.; Estre, N. ...
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment,
09/2005, Letnik:
549, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Odprti dostop
Due to the high track multiplicity in the final states expected in proton collisions at the LHC experiments, novel vertex reconstruction algorithms are required. The vertex reconstruction problem can ...be decomposed into a pattern recognition problem (“vertex finding”) and an estimation problem (“vertex fitting”). Starting from least-squares methods, robustifications of the classical algorithms are discussed and the statistical properties of the novel methods are shown. A whole set of different approaches for the vertex finding problem is presented and compared in relevant physics channels.
New developments in vertex reconstruction for CMS Frühwirth, R; Prokofiev, K; Speer, T ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
04/2003, Letnik:
502, Številka:
2
Journal Article
Recenzirano
Presently, two kinds of least-squares (LS) vertex fits are implemented in the ORCA reconstruction program (
http://cmsdoc.cern.ch/orca) of the CMS experiment (
http://cmsinfo.cern.ch): a full Kalman ...filter, and an iterative fit working with the impact points of the tracks with respect to an expansion point. In this contribution we concentrate on nonlinear, robust estimators which are insensitive to outlying observations. The aim is to improve the recognition of outliers, to lower the bias in the final fit, and to achieve a better separation between primary vertices and secondary vertices. Robust vertex estimates should also be good starting points for more complex algorithms, such as a multivertex fit.
Sensitivity of robust vertex fitting algorithms D'Hondt, J.; Fruhwirth, R.; Vanlaer, P. ...
IEEE transactions on nuclear science,
2004-Oct., 2004-10-00, 20041001, Letnik:
51, Številka:
5
Journal Article
Recenzirano
Odprti dostop
Robust vertex fitting algorithms are expected to improve the knowledge of the vertex position and of its uncertainty in the presence of mismeasured or misassociated tracks. Such contaminations are ...likely to happen in real data as well as in realistic detector simulations. This paper describes a simulation study of the sensitivity of two types of robust algorithms: a trimmed least squares estimator and an adaptive estimator. The statistical properties of the algorithms are studied as a function of the source and the level of contamination, and compared to the results obtained with classical least squares estimators. Two typical event topologies are studied: one resembling a high multiplicity primary vertex with a possible contamination from a nearby vertex and one resembling a low multiplicity secondary vertex in a jet.
Tracking in CMS: software framework and tracker performance Khanov, A; Lenzi, M; Todorov, T ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2002, Letnik:
478, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Tracking in LHC experiments requires reconstruction software that is able to deal with high hit multiplicity and complex detector geometry. The software framework should also be flexible enough to ...allow online event reconstruction and selection at high trigger levels. We present an object-oriented framework that fulfills these constraints. We describe two track reconstruction algorithms currently implemented within this framework, with a comparison of their performance at high multiplicity of noise hits. We present the performance of the CMS tracker in terms of momentum and impact parameter resolutions, evaluated by means of simulation studies.
Simulation study of silicon and gaseous tracking detectors Beaumont, W; Beckers, T; De Lentdecker, G ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
02/2002, Letnik:
478, Številka:
1
Journal Article
Recenzirano
The performance of microstrip gaseous counters (MSGC, MSGC + GEM) and silicon microstrip sensors has been studied in view of their use in high luminosity tracking applications. Simulations of signal ...development in the detectors and subsequent signal treatment in the readout electronics were performed. The simulation results are compared with experimental data obtained in test beams.
Robust vertex fitters Speer, T.; Frühwirth, R.; Vanlaer, P. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
10/2006, Letnik:
566, Številka:
1
Journal Article
Recenzirano
While linear estimators are optimal when the model is linear and all random noise is Gaussian, they are very sensitive to outlying tracks. Non-linear vertex reconstruction algorithms offer a higher ...degree of robustness against such outliers. Two of the algorithms presented, the
Adaptive filter and the
Trimmed Kalman Filter are able to down-weight or discard these outlying tracks, while a third, the
Gaussian-sum filter, offers a better treatment of non-Gaussian distributions of track parameter errors when these are modelled by Gaussian mixtures.
Studies of an MSGC equipped with a GEM grid as a tracking device Beaumont, W.; Beckers, T.; Troy, J.De ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
12/1998, Letnik:
419, Številka:
2-3
Journal Article
Recenzirano
The performance of a Micro Strip Gas Counter (MSGC) equipped with a Gas Electron Multiplier (GEM) has been studied in a cosmic hodoscope. Using Ne/DME gas mixtures, measurements have been performed ...to study gain, transparency and spatial resolution.
First results of Micromegas detector with fast integrated electronics Jeanneau, F; Benhammou, Y; Blaes, R ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
2000, Letnik:
450, Številka:
2
Journal Article
Recenzirano
A wedge-shaped Micromegas detector has been tested with a fast integrated electronics (PREMUX128). Due to the large capacitance of this detector, special care has been taken to protect electronics ...from possible streamers in the signal collection area; a study of the discharge mechanism is reported here. The signal-to-noise, spatial resolution and efficiency have been evaluated with a 100 GeV/
c muons beam at the CERN X5 experimental area. Then the rate capability of this detector has been studied with a high rate
300
MeV/c
pions beam at the Paul Scherrer Institute (PSI).
Operation of microstrip gas counters with DME-based gas mixtures Bouhali, O; Udo, F; Van Doninck, W ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/1998, Letnik:
413, Številka:
1
Journal Article
Recenzirano
This paper reports on the operation of MicroStrip Gas Counters (MSGC) with several dimethylether (DME)-based gas mixtures. We present measurements of signal amplitude, detection efficiency and ...spatial resolution for minimum ionizing particles. We also show measurements of electron drift velocity and transverse diffusion coefficient in the counting gases considered. These results are discussed regarding the use of MSGC’s for tracking at high-energy physics experiments that have to deal with high particle rates.
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