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Nonextensive thermal sources of cosmic rays

100%
Wilk G., Włodarczyk Z.
Open Physics
|
2010
|
vol. 8
|
issue 5
726-736
EN
The energy spectrum of cosmic rays exhibits power-like behavior with a very characteristic ‘knee’ structure. We consider a possibility that such a spectrum could be generated by some specific nonstatistical temperature fluctuations in the source of cosmic rays with the ‘knee’ structure reflecting an abrupt change of the pattern of such fluctuations. This would result in a generalized nonextensive statistical model for the production of cosmic rays. The possible physical mechanisms leading to these effects are discussed together with the resulting chemical composition of the cosmic rays, which follows the experimentally observed abundance of nuclei.
2
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Significance of the second dip in the ultra-high energy cosmic ray spectrum

80%
Wibig T.
Open Physics
|
2007
|
vol. 5
|
issue 4
528-538
EN
A new feature in the spectrum of ultra high energy cosmic rays (UHECR) has been announced in the paper by Berezinsky, Gazizov and Kachelrieβ. The ratio of the solution of the exact transport equation to its solution in the continuous energy loss limit shows intriguing features which, according to the Authors, are related to the very nature of the energy loss processes of UHECR: the very sharp second dip predicted at 6.3 × 1019 eV can be used as an energy calibration point and also as the UHECR mass indicator for big future cosmic ray experiments. In the present paper we would like to advocate that this statement is an overinterpretation. The second dip is a result of an inappropriate approximation used, and thus it cannot help to understand the nature of UHECR in any way.
3
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Emulsion chamber observations of Centauros, aligned events and the long-flying component

80%
Kempa J., Pattison B., Gładysz-Dziaduś E., Jones L., Mukhamedshin R., Tamada M., Włodarczyk Z.
Open Physics
|
2012
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vol. 10
|
issue 4
723-741
EN
The cosmic ray emulsion chamber community has reported several unusual phenomena which are also relevant to experiments at the current high-energy accelerators, in particular the Fermilab Tevatron Collider and the CERN Large Hadron Collider (LHC). A summary of the ”Cosmic Rays at Mountain Altitude” workshop held at Plock (Poland, September 2010) is given.
4
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Tachyonic field theory and neutrino mass running

61%
Jentschura U.
Open Physics
|
2012
|
vol. 10
|
issue 4
749-762
EN
In this paper three things are done. (i) We investigate the analogues of Cerenkov radiation for the decay of a superluminal neutrino and calculate the Cerenkov angles for the emission of a photon through a W loop, and for a collinear electron-positron pair, assuming the tachyonic dispersion relation for the superluminal neutrino. The decay rate of a freely propagating neutrino is found to depend on the shape of the assumed dispersion relation, and is found to decrease with decreasing tachyonic mass of the neutrino. (ii)We discuss a few properties of the tachyonic Dirac equation (symmetries and plane-wave solutions), which may be relevant for the description of superluminal neutrinos seen by the OPERA experiment, and discuss the calculation of the tachyonic propagator. (iii) In the absence of a commonly accepted tachyonic field theory, and in view of an apparent “running” of the observed neutrino mass with the energy, we write down a model Lagrangian, which describes a Yukawa-type interaction of a neutrino coupling to a scalar background field via a scalar-minus-pseudoscalar interaction. This constitutes an extension of the standard model. If the interaction is strong, then it leads to a substantial renormalization-group “running” of the neutrino mass and could potentially explain the experimental observations.
5
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Osłabianie promieniowania gamma w chondrytach zwyczajnych

61%
Kaczmarzyk M.
Acta Societatis Metheoriticae Polonorum
|
2019
|
vol. 10
40-50
EN
This paper elaborates on gamma rays attenuation in ordinary chondrites. Highly penetrating gamma radiation is emitted as a result of inelastic collisions of ultra-high energy cosmic particles with bulk matter, such as spacecraft hulls. Resources mined from Solar System small bodies may present an alternative construction material for spacecraft cosmic rays shields, which explains research on ionizing radiation attenuation in meteorites. A custom-made, shielded research workstation was constructed to analyse ionizing radiation absorption in pulverized materials. Using the workstation, gamma rays attenuation experiment was performed on pulverized ordinary chondrite – a meteorite originating from S-type asteroid. The experiment resulted in obtaining gamma ray mass attenuation coefficient of S-type chondritic asteroid matter. Obtained results were analysed and final conclusions were formulated. Per unit mass, ordinary chondrites exhibit better gamma rays attenuation properties than any radiation shielding material contemporarily used in astronautics.
PL
W niniejszej pracy poruszono zagadnienie pochłaniania promieniowania gamma w materiale budującym meteoryty należące do grupy chondrytów zwyczajnych, które pochodzą z planetoid typu S. Wysoce przenikliwe promieniowanie gamma powstaje w przestrzeni kosmicznej m.in. jako efekt oddziaływania pierwotnego promieniowania kosmicznego z ośrodkami materialnymi. Materiał pozyskany z małych ciał Układu Słonecznego może stanowić alternatywny budulec ciężkich osłon radiacyjnych statków kosmicznych, co uzasadnia prowadzenie badań nad pochłanianiem promieniowania jonizującego w meteorytach. Opisano tu eksperyment, do celów którego wykonano autorskiej konstrukcji stanowisko badawcze do analizy pochłaniania promieniowania jonizującego w materiałach sypkich. Przy pomocy tego stanowiska, wykorzystując radioaktywny izotop 60Co, określono masowy współczynnik absorbcji promieniowania gamma w sproszkowanym chondrycie zwyczajnym, a otrzymany wynik porównano z wartością obliczoną teoretycznie. W pracy przeprowadzono szczegółową analizę uzyskanych wyników i sformułowano wnioski płynące z przeprowadzonego eksperymentu. Na jednostkę masy, chondryty zwyczajne lepiej osłabiają promieniowanie gamma niż jakiekolwiek materiały osłonowe stosowane obecnie w astronautyce.
6
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Propagation of Ultra-High Energy Cosmic Rays in Extragalactic Magnetic Fields

61%
Wibig T.
Open Physics
|
2004
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vol. 2
|
issue 2
277-299
EN
In this paper we will discuss the problem of Ultra High Energy Cosmic Rays (UHECR) and show that the idea of a Single Source Model established by Erlykin and Wolfendale (1997) to explain the features seen in cosmic ray energy spectra around the 1015 eV region can be successfully applied also for the much higher energies. The propagation of UHECR (of energies higher than 1019 eV) in extragalactic magnetic fields can no longer be described as a random walk (diffusion) process and the transition to rectilinear propagation gives a possible explanation for the so-called Greisen-Zatzepin-Kuzmin (GZK) cut-off which still remains an open question after almost 40 years. A transient “single source” located at a particular distance and producing UHECR for a finite time is the proposed solution.
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