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Testování polovodičových detektorů typu DEPFET
Malina, Lukáš ; Kodyš, Peter (advisor) ; Doležal, Zdeněk (referee)
DEPFET pixel detectors were developed more than 20 years ago and they are still being improved, for example on Belle II experiment in Japan. In this thesis we studied the properties of readout cycle of detector matrix and the movement of counted hit positions close to the edges of DEPFET matrix, the which is reffered to as edge effect. The main goal of this work was to familiarize with particle detectors and their principles, especially with DEPFET matrices, to set up laser test system and to write ROOT macro for measurement automatization, run the measurement and analyze obtained data. For this purpose we used red 3 nanosecond long laser pulses, moving stages with very fine step and two connected pulse generators. As a result, the voltage between the outer ring and the inner part of the detector active area was optimalised, the edge effect was reduced by a factor of 2. The time properties of readout cycle, the time period of charge clearing and the time in which is the matrix read out, have been found.
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Rozpoznávání drah částic v pixelovém detektoru typu Timepix
Čermák, Jakub ; Čermák, Pavel (advisor) ; Doležal, Zdeněk (referee)
In current particle physics field, the progressive detection technologies are used. The pixel detectors are one of them. These detectors are divided into small subdetectors (pixels), which allow viewing exact tracks of the detected particles. This thesis defines criteria for mathematical description of the shape of the particle tracks of different kinds (e-, γ, p, α, μ) and compares several methods used for a classification -neural networks, decision trees and others. The Pixa software was implemented to process the data measured by pixel detectors. This software implements the characteristics and classification methods and creates statistical and other physical results.
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Measurement of Time-Dependent CP Violation in B0 → ŋcK0S at Belle Experiment, Optimization Studies of the Belle II Vertex Detector
Drásal, Zbyněk
Title: Measurement of Time-Dependent CP Violation in B0 → ηcK0 S at Belle Experi- ment, Optimization Studies of the Belle II Vertex Detector Author: Zbyněk Drásal Department: Institute of Particle and Nuclear Physics Supervisor: Dr. Zdeněk Doležal, IPNP Supervisor's e-mail address: Zdenek.Dolezal@mff.cuni.cz Abstract: This doctoral thesis deals with two independent topics. In the first part we present a measurement of branching ratio(s) and time-dependent CP violation parame- ters in B0 (B± ) → ηcK0 S(K± ), ηc → p¯p. The values of CP violation parameters have been found as follows: sin 2φ1, denoted as an SCP parameter, equals: SCP = 0.68+0.38 −0.46±0.13syst, the direct CP violation parameter, denoted as an ACP , is: ACP = 0.00+0.23 −0.31 ± 0.08syst. These results have been obtained with the final data sample of 772×106 B ¯B pairs collected at Υ(4S) resonance with a Belle detector at the KEKB e+ e− asymmetric collider machine in Japan. In the second part, we present our approach to the Monte Carlo (MC) simula- tion of Belle II vertex detector and its response to high energy particles. Belle II represents an upgrade of current Belle experiment and its designed vertex detector will consist of 2 layers of Depfet pixel detectors (PXD) and 4 layers of double-sided silicon micro-strip detectors (SVD). The MC...
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Measurement of Time-Dependent CP Violation in B0 → ŋcK0S at Belle Experiment, Optimization Studies of the Belle II Vertex Detector
Drásal, Zbyněk
Title: Measurement of Time-Dependent CP Violation in B0 → ηcK0 S at Belle Experi- ment, Optimization Studies of the Belle II Vertex Detector Author: Zbyněk Drásal Department: Institute of Particle and Nuclear Physics Supervisor: Dr. Zdeněk Doležal, IPNP Supervisor's e-mail address: Zdenek.Dolezal@mff.cuni.cz Abstract: This doctoral thesis deals with two independent topics. In the first part we present a measurement of branching ratio(s) and time-dependent CP violation parame- ters in B0 (B± ) → ηcK0 S(K± ), ηc → p¯p. The values of CP violation parameters have been found as follows: sin 2φ1, denoted as an SCP parameter, equals: SCP = 0.68+0.38 −0.46±0.13syst, the direct CP violation parameter, denoted as an ACP , is: ACP = 0.00+0.23 −0.31 ± 0.08syst. These results have been obtained with the final data sample of 772×106 B ¯B pairs collected at Υ(4S) resonance with a Belle detector at the KEKB e+ e− asymmetric collider machine in Japan. In the second part, we present our approach to the Monte Carlo (MC) simula- tion of Belle II vertex detector and its response to high energy particles. Belle II represents an upgrade of current Belle experiment and its designed vertex detector will consist of 2 layers of Depfet pixel detectors (PXD) and 4 layers of double-sided silicon micro-strip detectors (SVD). The MC...
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Measurement of Time-Dependent CP Violation in B0 → ŋcK0S at Belle Experiment, Optimization Studies of the Belle II Vertex Detector
Drásal, Zbyněk ; Doležal, Zdeněk (advisor) ; Vrba, Václav (referee) ; Schwanda, Christoph (referee)
Title: Measurement of Time-Dependent CP Violation in B0 → ηcK0 S at Belle Experi- ment, Optimization Studies of the Belle II Vertex Detector Author: Zbyněk Drásal Department: Institute of Particle and Nuclear Physics Supervisor: Dr. Zdeněk Doležal, IPNP Supervisor's e-mail address: Zdenek.Dolezal@mff.cuni.cz Abstract: This doctoral thesis deals with two independent topics. In the first part we present a measurement of branching ratio(s) and time-dependent CP violation parame- ters in B0 (B± ) → ηcK0 S(K± ), ηc → p¯p. The values of CP violation parameters have been found as follows: sin 2φ1, denoted as an SCP parameter, equals: SCP = 0.68+0.38 −0.46±0.13syst, the direct CP violation parameter, denoted as an ACP , is: ACP = 0.00+0.23 −0.31 ± 0.08syst. These results have been obtained with the final data sample of 772×106 B ¯B pairs collected at Υ(4S) resonance with a Belle detector at the KEKB e+ e− asymmetric collider machine in Japan. In the second part, we present our approach to the Monte Carlo (MC) simula- tion of Belle II vertex detector and its response to high energy particles. Belle II represents an upgrade of current Belle experiment and its designed vertex detector will consist of 2 layers of Depfet pixel detectors (PXD) and 4 layers of double-sided silicon micro-strip detectors (SVD). The MC...
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Rozpoznávání drah částic v pixelovém detektoru typu Timepix
Čermák, Jakub ; Čermák, Pavel (advisor) ; Doležal, Zdeněk (referee)
In current particle physics field, the progressive detection technologies are used. The pixel detectors are one of them. These detectors are divided into small subdetectors (pixels), which allow viewing exact tracks of the detected particles. This thesis defines criteria for mathematical description of the shape of the particle tracks of different kinds (e-, γ, p, α, μ) and compares several methods used for a classification -neural networks, decision trees and others. The Pixa software was implemented to process the data measured by pixel detectors. This software implements the characteristics and classification methods and creates statistical and other physical results.
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Testování polovodičových detektorů typu DEPFET
Malina, Lukáš ; Kodyš, Peter (advisor) ; Doležal, Zdeněk (referee)
DEPFET pixel detectors were developed more than 20 years ago and they are still being improved, for example on Belle II experiment in Japan. In this thesis we studied the properties of readout cycle of detector matrix and the movement of counted hit positions close to the edges of DEPFET matrix, the which is reffered to as edge effect. The main goal of this work was to familiarize with particle detectors and their principles, especially with DEPFET matrices, to set up laser test system and to write ROOT macro for measurement automatization, run the measurement and analyze obtained data. For this purpose we used red 3 nanosecond long laser pulses, moving stages with very fine step and two connected pulse generators. As a result, the voltage between the outer ring and the inner part of the detector active area was optimalised, the edge effect was reduced by a factor of 2. The time properties of readout cycle, the time period of charge clearing and the time in which is the matrix read out, have been found.
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Vývoj křemíkového detektoru pro experiment Belle II
Bilka, Tadeáš ; Kodyš, Peter (advisor) ; Černý, Karel (referee)
This bachelor thesis describes a simulation of the DEPFET pixel semiconductor detector. The DEPFET detector is a key part of a newly constructed Belle II particle detector being built in KEK, Japan. The simulation is made as a package for the basf2 framework, developed for the Belle II experiment. The goal of this thesis was to learn about the Belle II experiment, DEPFET pixel detector and the basf2 framework and to develop a simulation environment, depicting experimental setup at CERN's SPS accelerator in 2009. First part of this thesis describes the Belle II detector, the basf2 framework and summarizes basic information about silicon particle detectors, especially about the DEPFET technology. A task for the analysis of the data is to evaluate residuals after particle track fitting and cluster information in the pixel detector. Finally the simulation with thinned DEPFET sensor being developed for the Belle II is done.
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The methodology for visualization of the internal structure of the painting using novel x-ray based methods
Hradilová, Janka ; Hradil, David ; Trmalová, Olga ; Žemlička, Jan
Aim of the methodology is to involve the newly tested a newly developed methods, which allow displaying an internal structure of a painting, into the routine conservation/restoration research. The methodology is yet specifically focused only on methods using X-rays, i.e. X-ray radiography (XRR) and X-ray fluorescence (XRF) (including macroscopic XRF scanning). The methodology includes testing the radiographic equipment with pixel detectors, which has been newly developed within the project, and assesses its contribution to the practical survey of painting techniques reflecting its exceptional spatial resolution, materials sensitivity and mobility.
Fulltext:  PDF; PDF
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Energy sensitive X-ray radiography for the non-destructive inspection of historical paintings
Žemlička, J. ; Jakůbek, J. ; Hradil, David ; Hradilová, J. ; Kroupa, M. ; Mislerová, H.
The technical composition of painted artworks is usually very complex and they belong to the most sophisticated cultural heritage artefacts. In the field of their inspection there is a rising demand for the non-destructive imaging and analytical methods which are able to reveal the inner composition of investigated objects. Several non-invasive methods based on the interaction of ionizing radiation with the matter have been successfully utilized during the last decades. These methods can be divided into two main groups. The better known are transmission methods (e.g. classical X-ray radiography) the less-used are emission methods (e.g. X-ray fluorescence imaging). The quality of the obtained image is highly dependent on the imaging characteristics of the used detector. The presently used ones (CCD cameras and CMOS sensors) create the image from analogue signal by the charge integration. This image is usually degraded by the presence of noise. This complication is exceeded by novel pixel detectors of Medipix family based on single particle digital counting. Furthermore these devices offer very high contrast (in principle unlimited) in the obtained image. The image can be acquired with spatial resolution better than one micrometer. Another advantage of these detectors is their ability to directly measure the energy of incident particles. This feature can be used for energy sensitive X-ray radiography (i.e. multi-channel images) and X-ray fluorescence mapping of the surface elemental composition. For the purposes of this work the laboratory ALMA in Prague prepared several multilayer samples of paints using different pigments. The results of mentioned methods applied on the test samples are summarized in this article. The first goal of these measurements is to build a comprehensive methodology for the application of these procedures in the laboratory.
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