Heart Disease A Textbook of Cardiovascular Medicine

Nuclear multifragmentation and phase transition for hot nuclei

Excitation functions of flow and stopping observables for the Au+Au system at energies from 40 to 1500 MeV per nucleon are presented. The systematics were obtained by merging the results of the INDRA and FOPI experiments, both performed at the GSI facility. The connection to the nuclear equation of state is discussed.

/pdf/systematics-of-stopping-and-flow-in-au-au-collisions-555sj5e0yp.pdf

Systematics of stopping and flow in Au+Au collisions

Lightning produces electromagnetic fields and waves in all frequency ranges. In the extremely low frequency (ELF) range below 100 Hz, the global Schumann Resonances (SR) are excited at frequencies of 8 Hz, 14 Hz, 20 Hz, etc. This review is aimed at the reader generally unfamiliar with the Schumann Resonances. First some historical context to SR research is given, followed by some theoretical background and examples of the extensive use of Schumann resonances in a variety of lightning-related studies in recent years, ranging from estimates of the spatial and temporal variations in global lighting activity, connections to global climate change, transient luminous events and extraterrestrial lightning. Both theoretical and experimental results of the global resonance phenomenon are presented. It is our hope that this review will increase the interest in SR among researchers previously unfamiliar with this phenomenon.

https://www.mdpi.com/2073-4433/7/9/116/pdf

ELF Electromagnetic Waves from Lightning: The Schumann Resonances

We present the Hylaty geophysical station, a high-sensitivity and low-noise facility for extremely low frequency (ELF, 0.03–300 Hz) electromagnetic field measurements, which enables a variety of geophysical and climatological research related to atmospheric, ionospheric, magnetospheric, and space weather physics. The first systematic observations of ELF electromagnetic fields at the Jagiellonian University were undertaken in 1994. At the beginning the measurements were carried out sporadically, during expeditions to sparsely populated areas of the Bieszczady Mountains in the southeast of Poland. In 2004, an automatic Hylaty ELF station was built there, in a very low electromagnetic noise environment, which enabled continuous recording of the magnetic field components of the ELF electromagnetic field in the frequency range below 60 Hz. In 2013, after 8 years of successful operation, the station was upgraded by extending its frequency range up to 300 Hz. In this paper we show the station's technical setup, and how it has changed over the years. We discuss the design of ELF equipment, including antennas, receivers, the time control circuit, and power supply, as well as antenna and receiver calibration. We also discuss the methodology we developed for observations of the Schumann resonance and wideband observations of ELF field pulses. We provide examples of various kinds of signals recorded at the station.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1002/2014RS005400

Extremely low frequency electromagnetic field measurements at the Hylaty station and methodology of signal analysis

[1] Asymmetric resonance curves are observed in various resonance systems occurring in nature. The reason for such a shape of the resonance curves is an interaction of the standing waves field in the resonator with the field of traveling waves which transmit energy from sources to the resonator. This behavior can be observed in strongly damped electromagnetic resonators. The ELF wave propagation inside the Earth-ionosphere cavity is a good example of the simultaneous occurrence of resonance and transmission phenomena. In this paper we show that the transmission field component depends on the attenuation rate of the Earth-ionosphere cavity and the observer-source distance. Besides, the resonance curve asymmetry causes an evident diurnal variability of the resonance frequencies. The superposition of the two components at any point of the resonator makes the analysis of the Schumann resonance (SR) difficult. Here we suggest a field decomposition method that allows separating the resonance component from the transmission one. Owing to the decomposition, having a single measurement of the E or B field, it is possible, independently of the observer position, to study the physical properties of the resonator as well as to determine the localization and the intensity of sources. The field decomposition permits defining new resonator parameters such as reduced resonance frequencies and reduced quality factors, independent of the observer position inside the cavity. We believe that the application of the decomposition method in the analysis of the ELF observations yields a possibility of improving the accuracy of the determination of both the distances and intensities of the sources exciting the Earth-ionosphere resonator, as well as its own parameters.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2005JA011429

Studies of ELF propagation in the spherical shell cavity using a field decomposition method based on asymmetry of Schumann resonance curves

[1] The primary purpose of the research presented is to study solar variations in extremely low frequency (ELF) propagation parameters using Schumann resonance (SR) data from our irregular observations carried out in the East Carpathian mountains. The natural electromagnetic ELF fields in the Earth-ionosphere cavity (the global resonator) are strongly dependent on its resonance and propagation properties as well as on the global thunderstorm activity. Thus a determination of the global resonator parameters from Schumann resonances needs information about such signal properties, which depend only on physical conditions of the Earth-ionosphere cavity. To seek such signal properties, we consider the two-dimensional telegraph equation (TDTE) approach for describing propagation of ELF electromagnetic waves in a two-dimensional spherical transmission line model of the Earth-ionosphere cavity. We have set up a model consisting of a network of finite, homogeneous, one-dimensional transmission lines covering the sphere; with the square root dependence of the attenuation rate from frequency as a sufficient model for the study of the solar influence on global properties of the Earth-ionosphere cavity. Using this model, we have constructed useful formulae and algorithms connecting the observed parameters of Schumann resonances with the attenuation rate. This enables us to study the solar influence on the attenuation rate from diurnal observations of the NS-magnetic component of the ELF field measured at one station. As the measurements were carried out during both the minimum and the maximum of the solar cycle 23, we present in the work of Kuak et al. [2003] evidence for a change in the ELF attenuation rate in the Earth-ionosphere cavity with solar activity.

https://agupubs.onlinelibrary.wiley.com/doi/pdf/10.1029/2002JA009304

Solar variations in extremely low frequency propagation parameters: 1. A two‐dimensional telegraph equation (TDTE) model of ELF propagation and fundamental parameters of Schumann resonances

Characterization of reaction mechanisms in the

Gas ionization chambers of a special shape adapted for 4π detector systems are presented. Different anode wire configurations are discussed for three working gases: Ar + methane(10%), isobutane, and tetrafluoromethane.

Gas chambers for identification of charged particles in 4π systems

A prototype of a detector system for identification of charged complex fragments is presented. It contains 21 gas-Si telescopes, each of them covering a solid angle of about 42 msr. The system was tested with an alpha particle source as well as with beams of 26 MeV/ A 6 Li and 22 MeV/ A 14 N ions bombarding Cu, Ag and Tb targets.

S. Micek

Papers

Studies of ELF propagation in the spherical shell cavity using a field decomposition method based on asymmetry of Schumann resonance curves

Solar variations in extremely low frequency propagation parameters: 1. A two‐dimensional telegraph equation (TDTE) model of ELF propagation and fundamental parameters of Schumann resonances

Characterization of reaction mechanisms in the

Gas chambers for identification of charged particles in 4π systems

A simple multidetector system for intermediate mass fragments