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Phenomenological models inspired by QCD and their use in the analysis of ultra-high energy cosmic rays
Ebr, Jan ; Řídký, Jan (advisor) ; Leitner, Rupert (referee) ; Unger, Michael (referee)
Cosmic rays of energies above 1014 eV are detected mostly indirectly, by observing the extensive air showers they create in the atmosphere. Multiple experiments suggest that the current models of high-energy interactions do not describe the cosmic ray data perfectly, in particular when it comes to the prediction for the number of muons at ground. We present two models aiming to improve the description of the muon component, one based on the addition of particles with small momenta in the local center-of-mass frame of the high-energy hadronic interactions in the shower, the other on the addition of the so-called dark photons to the electromagnetic part of the shower. While we find the latter having no observable consequences, the former improves the agreement between observed and predicted amounts of muons both for the DELPHI cosmic ray data and for the measurements by the Pierre Auger Observatory. We also describe the FRAM telescope, a device used to monitor the atmosphere at the Pierre Auger Observatory, and its applications to the search for anomalous shower profiles and to the measurement of the aerosol content of the atmosphere, which is crucial for the analysis of data obtained by fluorescence detectors. 1
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Study of Interactions of Cosmic Rays at Ultra-high Energies
Nečesal, Petr ; Řídký, Jan (advisor) ; Vorobel, Vít (referee) ; Wagner, Vladimír (referee)
This thesis is dedicated to study of interactions of utra-high energy cosmic rays using measured data from the Pierre Auger Observatory, automatic alarm system called Shift Guard and analysis of correlation of temperature and detector response. The Pierre Auger Observatory is the largest experiment to study ultra-high energy cosmic rays. The assumed relation between temperature and fluorescence detector response is studied together with descriptive temperature analysis, which shows that the air-conditioning system is not able to stabilize temperature enough. The temperature influence on camera response is investigated in order to measure the calibration correction factor. Shift Guard - the alarm system dedicated to protect fluorescence detectors and data taking is introduced and its functionality is described. The alarm system informs shifters about some events and situations that can endanger detector or deteriorate data quality. The basic parameters and alarm system logic are described together with light and sound signals. The discrepancy between measured and predicted number of muons at ground level calculated by EAS generators is showed and possible sources of this disagree- ment are studied. The result of massive dark photons decay in EAS as one of exotic muon source is presented. The analysis...
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Credit risk regulation and management and its influence on US economy since 80's until today
Řídký, Jan ; Jílek, Josef (advisor) ; Mládek, Josef (referee)
This thesis describes an impact of credit risk management and credit risk regulation on the volume and quality of credits. Consequently there is an influence on economic activity of people and companies, price level and business cycle. In the thesis the basic principles of credit risk management and regulations are described. The volume of granted credit determines the probability of default. If there is an option to transfer a credit risk to the third party, volume of granted credits increases. The volume of credit depends also on the regulatory duty to hold an adequate amount of capital. In the case the banks find the way to diminish this regulatory capital, the volume of credit increases. Credit activity of banks boosts economic activity of people and companies and it has an impact on the price level. The option of credit risk transfer to the third party together with high saturation of credit market leads to taking higher risk by lenders. At the end it has an impact on the business cycle.
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Zkušenosti s měřením reflexních vrstev u zrcadel používaných pro projekt Pierre Auger
Pech, Miroslav ; Hrabovský, Miroslav ; Schovánek, Petr ; Křepelka, Jaromír ; Palatka, Miroslav ; Nožka, Libor ; Mandát, Dušan ; Rössler, T. ; Řídký, Jan ; Boháčová, Martina
The Pierre Auger Observatory is designed for study of the universe's high energy particles, which evolve in the high layers of the atmosphere, where an elementary particle strikes with energy above 10.sup.19./sup. eV (1.6 J!). However, there is no scientific consensus about cosmic ray origin. The Auger Observatory is projected to gather the data needed to solve that puzzle. One of the detection technique is to observe these showers by fluorescent detectors, which are able to record the cascade development where the secondary particle causes atmospheric nitrogen to fluoresce.
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Light mirrors for VHE astronomy telescopes
Palatka, Miroslav ; Hrabovský, Miroslav ; Schovánek, Petr ; Vlček, Martin ; Řídký, Jan ; Grygar, Jiří ; Soukup, Ladislav ; Prouza, Michael ; Boháčová, Martina
The overview of light (weight) mirrors used in VHE astronomy telescopes is presented. The mirrors, which were developed in our laboratory are discribed.
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Production of mirror systems for cosmic rays detectors
Vlček, Martin ; Schovánek, Petr ; Palatka, Miroslav ; Hrabovský, Miroslav ; Řídký, Jan ; Grygar, Jiří ; Soukup, Ladislav ; Prouza, Michael ; Boháčová, Martina ; Nosek, D.
Joint Laboratory of Optics of Palacky University and Institute of Physics of the Academy of Science of the Czech Republic have cooperated and still works on several prestigious international projects of atmospheric optical detectors of cosmic rays.We deal with two French projects with international collaboration placed in French Pyrenees in Themis. These projects are CAT and Celesic.
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