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Functional simulator of the energetic electron detector from the TARANIS project
Enžl, Jakub ; Přech, Lubomír (advisor) ; Němeček, Zdeněk (referee)
Over a signi cant period of time there have been observations of storm-connected phenomena - so called Transient Luminous Events (TLE). In order to perform new measurements, a microsatellite is being developed under a project called TARANIS. The microsatellite is to carry a device designed to measure high-energy electrons IDEE. Its analyser developed at the Department of Surface and Plasma Science (Faculty of Mathematics and Physics, Charles University) should perform overall control of the detector and processing of registered data. The analyzer will also generate an Alert signal to inform other TARANIS devices whenever TLE-related event such as Relativistic Runaway Electon burst is observed. In order to test the analyzer an 4IDEE detector simulator is being developed. It's task is to generate data and send it to the analyzer. The data should be consistent with the ones expected to be measured during TLE. Another phenomenon to be studied by TARANIS is lightning-induced electron precipitation. Registration of such data will be simulated as well.
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Solar wind helium abundance variations
Cagaš, Petr ; Šafránková, Jana (advisor) ; Enžl, Jakub (referee)
The thesis presents results of one-year measurements of solar wind helium ion abundance variations with the BMSW instrument on-board the SPEKTR-R spacecraft. The BMSW instrument was designed and built for fast measurements of the solar wind and can obtain a complete cumulative distribution function of solar wind particles every 1.5 s. A statistical study of the data shows that in spite of the current prevailing opinion, abrupt changes in the relative helium abundance do not correlate with the changes in other parameters of the solar wind and are therefore likely caused by in-transit turbulence that contributes to the solar wind heating and leads to rise of the solar wind temperature with the helium content.
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Magnetic reconnection in the solar wind
Enžl, Jakub ; Přech, Lubomír (advisor)
Magnetic reconnection is a fundamental process that changes magnetic field configuration and converts a magnetic energy to flow energy and plasma heating. It can be found in a plasma with frozen magnetic field lines at boundaries where different magnetic field topologies encounter each other and thin current sheets are created as it is typical in the solar wind. In the thesis, we have used spacecraft measurements of solar wind plasma and magnetic field to found magnetic reconnection exhausts. We analyze and compare them with theoretical predictions. The results of the statistical analysis oriented on re-distribution of the magnetic energy in reconnection showed that both a portion of the energy deposited into heat as well as the energy spent on an acceleration of the exhaust plasma increase with the magnetic shear angle in accord with the increase of the magnetic flux available for reconnection. Moreover, we identify unusual events in the solar wind; we found magnetic reconnection exhausts accompanied by one or two side jets and explained their possible causes.
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Magnetic reconnection in the solar wind
Enžl, Jakub ; Přech, Lubomír (advisor)
Magnetic reconnection is a fundamental process that changes magnetic field configuration and converts a magnetic energy to flow energy and plasma heating. It can be found in a plasma with frozen magnetic field lines at boundaries where different magnetic field topologies encounter each other and thin current sheets are created as it is typical in the solar wind. In the thesis, we have used spacecraft measurements of solar wind plasma and magnetic field to found magnetic reconnection exhausts. We analyze and compare them with theoretical predictions. The results of the statistical analysis oriented on re-distribution of the magnetic energy in reconnection showed that both a portion of the energy deposited into heat as well as the energy spent on an acceleration of the exhaust plasma increase with the magnetic shear angle in accord with the increase of the magnetic flux available for reconnection. Moreover, we identify unusual events in the solar wind; we found magnetic reconnection exhausts accompanied by one or two side jets and explained their possible causes.
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Magnetic reconnection in the solar wind
Enžl, Jakub ; Přech, Lubomír (advisor) ; Bárta, Miroslav (referee) ; Kulhánek, Petr (referee)
Magnetic reconnection is a fundamental process that changes magnetic field configuration and converts a magnetic energy to flow energy and plasma heating. It can be found in a plasma with frozen magnetic field lines at boundaries where different magnetic field topologies encounter each other and thin current sheets are created as it is typical in the solar wind. In the thesis, we have used spacecraft measurements of solar wind plasma and magnetic field to found magnetic reconnection exhausts. We analyze and compare them with theoretical predictions. The results of the statistical analysis oriented on re-distribution of the magnetic energy in reconnection showed that both a portion of the energy deposited into heat as well as the energy spent on an acceleration of the exhaust plasma increase with the magnetic shear angle in accord with the increase of the magnetic flux available for reconnection. Moreover, we identify unusual events in the solar wind; we found magnetic reconnection exhausts accompanied by one or two side jets and explained their possible causes.
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Solar wind helium abundance variations
Cagaš, Petr ; Šafránková, Jana (advisor) ; Enžl, Jakub (referee)
The thesis presents results of one-year measurements of solar wind helium ion abundance variations with the BMSW instrument on-board the SPEKTR-R spacecraft. The BMSW instrument was designed and built for fast measurements of the solar wind and can obtain a complete cumulative distribution function of solar wind particles every 1.5 s. A statistical study of the data shows that in spite of the current prevailing opinion, abrupt changes in the relative helium abundance do not correlate with the changes in other parameters of the solar wind and are therefore likely caused by in-transit turbulence that contributes to the solar wind heating and leads to rise of the solar wind temperature with the helium content.
|
|
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Functional simulator of the energetic electron detector from the TARANIS project
Enžl, Jakub ; Přech, Lubomír (advisor) ; Němeček, Zdeněk (referee)
Over a signi cant period of time there have been observations of storm-connected phenomena - so called Transient Luminous Events (TLE). In order to perform new measurements, a microsatellite is being developed under a project called TARANIS. The microsatellite is to carry a device designed to measure high-energy electrons IDEE. Its analyser developed at the Department of Surface and Plasma Science (Faculty of Mathematics and Physics, Charles University) should perform overall control of the detector and processing of registered data. The analyzer will also generate an Alert signal to inform other TARANIS devices whenever TLE-related event such as Relativistic Runaway Electon burst is observed. In order to test the analyzer an 4IDEE detector simulator is being developed. It's task is to generate data and send it to the analyzer. The data should be consistent with the ones expected to be measured during TLE. Another phenomenon to be studied by TARANIS is lightning-induced electron precipitation. Registration of such data will be simulated as well.
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