scholarly journals Influence of the Earth's ring current strength on the Størmer's allowed and forbidden regions of charged particles motion

2018 ◽  
Author(s):  
Alexander S. Lavrukhin ◽  
Igor I. Alexeev ◽  
Ilya V. Tyutin
Keyword(s):  
Ring Current ◽  
Charged Particles ◽  
Current Strength ◽  
Trapping Region ◽  
Trapped Particles ◽  
The Earth ◽  
Forbidden Regions ◽  
Trapping Regions ◽  
Critical Ring ◽  
Earth’S Radiation Belt

Abstract. Størmer's particles' trapping regions for a planet with an intrinsic dipolar magnetic field are considered, taking into account the ring current which arises due to the trapped particles drift for the case of Earth. The influence of the ring current on the particles' trapping regions topology is investigated. It is shown that a critical strength of the ring current exists, under which further expansion of the trapping region is no longer possible. Before reaching this limit, the dipole field, although deformed, retains two separated Størmer regions. After transition of critical magnitude, the trapping region opens up and charged particles, which form the ring current, get the opportunity to leave it (go to infinity or come to the trapping region from infinity), thus decreasing the ring current strength. Numerical calculations have been performed for protons with typical energies of Earth's radiation belt and ring current. For the Earth case, the Dst index for the critical ring current strength is calculated.

scholarly journals Influence of the Earth's ring current strength on Størmer's allowed and forbidden regions of charged particle motion

2019 ◽  
Vol 37 (4) ◽  
pp. 535-547
Author(s):  
Alexander S. Lavrukhin ◽  
Igor I. Alexeev ◽  
Ilya V. Tyutin
Keyword(s):  
Radiation Belt ◽  
Ring Current ◽  
Current Strength ◽  
Trapping Region ◽  
Trapped Particles ◽  
The Earth ◽  
Forbidden Regions ◽  
Trapping Regions ◽  
Critical Ring ◽  
Earth’S Radiation Belt

Abstract. Størmer's particles' trapping regions for a planet with an intrinsic dipolar magnetic field are considered, taking into account the ring current which arises due to the trapped particles' drift for the case of the Earth. The influence of the ring current on the particle trapping regions' topology is investigated. It is shown that a critical strength of the ring current exists under which further expansion of the trapping region is no longer possible. Before reaching this limit, the dipole field, although deformed, retains two separated Størmer regions. After transition of critical magnitude, the trapping region opens up, and charged particles, which form the ring current, get the opportunity to leave it, thus decreasing the ring current strength. Numerical calculations have been performed for protons with typical energies of the Earth's radiation belt and ring current. For the Earth's case, the Dst index for the critical ring current strength is calculated.

The Plasmasphere During Major Geomagnetic Storms: Analysis Of Trapped Particles In The Outer Radiation Belt

2020 ◽  
Author(s):  
Jessy Matar ◽  
Benoit Hubert ◽  
Stan Cowley ◽  
Steve Milan ◽  
Zhonghua Yao ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electric Field ◽  
Geomagnetic Field ◽  
Radiation Belt ◽  
Ring Current ◽  
Geomagnetic Storms ◽  
Outer Radiation Belt ◽  
Trapped Particles ◽  
The Earth ◽  
Field Lines

<p> The coupling between the Earth’s magnetic field and the interplanetary magnetic field (IMF) transported by the solar wind results in a cycle of magnetic field lines opening and closing generally known as the Dungey substorm cycle, mostly governed by the process of magnetic reconnection. The geomagnetic field lines can therefore have either a closed or an open topology, i.e. lower latitude field lines are closed (map from southern ionosphere to the northern), while higher latitude field lines are open (map from one polar ionosphere into interplanetary space). Closed field lines can trap electrically charged particles that bounce between mirror points located in the North and South hemispheres while drifting in longitude around the Earth, forming the plasmasphere, the radiation belts and the ring current. The outer boundary of the plasmasphere is the plasmapause. Its location is mostly driven by the interplay of the corotation electric field of ionospheric origin, and the convection electric field that results from the interaction between the IMF and the geomagnetic field. At times of prolonged intense coupling between these fields, the response of the magnetosphere becomes global and a geomagnetic storm develops. The ring current created by the motion of the trapped energetic particles intensifies and then decays as the storm abates. This study aims to find a possible relationship between the evolution of the trapped population and the process of magnetic reconnection during storm times. The EUV instrument on board the NASA-IMAGE spacecraft observed the distribution of the trapped helium ions (He+) in the plasmasphere. We consider several cases of intense geomagnetic storms observed by the IMAGE satellite. We identify the plasmapause location (Lpp) during those cases. We find a strong correlation between the Dst index and Lpp. The ring current and the trapped particles are expected to vary during storms. We use the Tsyganenko magnetic field model to map the electric potential between the Heppner-Maynard boundary (HMB) in the ionosphere and the magnetosphere and estimate the voltage and electric field in the vicinity of the plasmapause. The ionospheric electric field is deduced from the ionospheric convection velocity measured by the SuperDARN (SD) radar network at high latitudes. The tangential electric field component of the moving plasmapause boundary is estimated from IMAGE-EUV observations of the plasmasphere and is compared with expectations based on the SD data. We combine measurements of the trapped population from IMAGE-EUV and IMAGE-FUV observations of the aurora to better understand and quantify the variability of the Earth's outer radiation belt during strong storms. The auroral precipitation at ionospheric latitude is studied using FUV imaging and compared to the He+ response during the storms.</p>

Ring current decay during storm recover phase: RBSP Observation

2020 ◽  
Author(s):  
Ao Chen ◽  
Chao Yue ◽  
Hongfei Chen ◽  
Qiugang Zong
Keyword(s):  
Charge Exchange ◽  
Ring Current ◽  
Current System ◽  
Charged Particles ◽  
Oxygen Ions ◽  
Current Decay ◽  
The Earth ◽  
Comparison Results ◽  
Wide Energy ◽  
Fitting In

<p>Ring curent is an important current system in the Earth's magnetosphere. Many charged particles, especially protons and oxygen ions, move around the Earth due to due to electromagnetic drifts, which forms the ring current. During the main phase of a magnetic storm, ring current will grow stronger while it will decay slowly during recover phase. It is thought that charge exchange is the main mechanism of ring current decay [Daglis et al., 1999]. Hereby we use charge exchange theories to calculate charge exchange lifetimes of protons and oxygen ions during recover phase of many storms. Meanwhile, data of RBSP has been used for fitting in order to get real lifetimes of  protons and oxygen ions. We compared the observed lifetimes with the theory prediction and find that  a. the two are close at high L(>4) values and low energy(<55keV) for protons, b. the two are similar in a wide energy(1~600keV) range but a relatively narrow L(different at different energies) range, c. day or night make little difference on the comparison results.</p>

scholarly journals 46. The störmertron

1958 ◽  
Vol 6 ◽  
pp. 446-447
Author(s):  
Willard H. Bennett
Keyword(s):  
Magnetic Field ◽  
Charged Particles ◽  
Mercury Vapor ◽  
Electron Gun ◽  
Conducting Film ◽  
New Developments ◽  
Electrically Conducting ◽  
The Earth ◽  
Magnetic Dipole Field ◽  
Glass Tubes

A tube has been developed in which the shapes of streams of charged particles moving in the earth's magnetic field can be produced accurately to scale. The tube has been named the Störmertron in honor of Carl Störmer who calculated many such orbits. New developments which have made this tube possible include a method for coating the inside of large glass tubes with a transparent electrically conducting film, and an electron gun producing gas-focused streams in less than ½ micron of mercury vapor, a nearly vapor-free grease joint, and a nearly vapor-free carbon black. The magnetic dipole field of the earth is simulated with an Alnico magnet capped with properly shaped soft iron caps. The stream is deflected using two pairs of yoke coils near the gun.

scholarly journals Note on horizontal receivers and transmitters in wireless telegraphy

1908 ◽  
Vol 81 (549) ◽  
pp. 394-397
Keyword(s):  
Wave Length ◽  
Current Strength ◽  
Transmitted Wave ◽  
Maximum Efficiency ◽  
Electric Force ◽  
Wave Detector ◽  
The Earth ◽  
Spark Gap ◽  
Wireless Telegraph ◽  
Formed Part

In a communication published in the ‘Proceedings,’ Mr. Marconi has given the results observed when a straight horizontal conductor is substituted for the usual vertical conductor employed as a transmitter or receiver at a wireless telegraph station. The object of the following note is to consider the theory of such an arrangement, or at any rate one aspect of it. The receiver, as being the more important, will be considered first. Let AB (fig. 1) represent the horizontal receiver, consisting of a straight conductor having the end A connected to a spark-gap CC 1 or other wave-detector. The electric oscillations in AB can be represented by a distribution of Hertzian oscillators along AB, and, if L denotes the current strength at any point of AB, it must satisfy the conditions L= 0 at B, the free end, and d L/ ds = 0 at A, since the electric force perpendicular to AB at A must vanish. If the distance of AB from the earth is not too small, the effect of the oscillations belonging to the image in the earth of AB on those in AB may be neglected, the radiation from the free end B will be approximately symmetrical with respect to AB, and the oscillations in AB are then approximately the same as if BA formed part .of a semi-infinite straight conductor in which a system of oscillations is being maintained, B being the free end and A. the first node from the free end; the wave-length of these oscillations is very approximately five times the length of AB, and therefore the receiver is of maximum efficiency when its length is one-fifth of the length of the transmitted wave, a result observed by Marconi. When the distance of AB from the earth is so small that the effect of the oscillations in the image of AB in the earth on the oscillations in AB is not negligible, the radiation from the free end B will not be symmetrical with respect to AB, but may be taken as being approximately symmetrical with respect to some line through B making an angle with BA; the wave-length of the oscillations in AB is therefore equal to the wave-length of the oscillations in a bent conductor joining AB; that is greater than five times the length of AB, and, therefore, in this case the receiving conductor has its maximum efficiency when its Length is somewhat less than one-fifth of the length of the transmitted wave, result also observed by Marconi. To examine the effect of the orientation of the receiver, consider a straight conductor BAB' twice the length of AB (fig. 2) and its image B 1 A 1 B 1 ' in the horizontal plane, A and A 1 being their middle points respectively.

scholarly journals THE MAGNETIC PROPERTIES MEASUREMENT OF COIL FOR GRAVITATIONAL ACCELERATION DETERMINATION

2020 ◽  
Vol 5 (2) ◽  
pp. 119-128
Author(s):  
Cherly Salawane ◽  
Supriyadi Supriyadi ◽  
Ronaldo Talapessy ◽  
Mirtha Yunitha Sari Risakotta
Keyword(s):  
Magnetic Field ◽  
Magnetic Properties ◽  
Field Strength ◽  
Electric Current ◽  
Graphical Method ◽  
Current Strength ◽  
Gravitational Acceleration ◽  
The Earth ◽  
The Magnetic Field ◽  
A Current

The value of the gravitational acceleration of the earth above the earth’s surface depends on the position of the latitude and longitude of the earth’s surface, in other words, because the shape of the earth’s surface is not round like a ball. The magnitude of gravity is not the same everywhere on the surface of the earth. The purpose of this study is to analyze the value of the earth’s gravitational acceleration in a laboratory using a current balance with a graphical method. Fluctuations in the value of the magnetic field strength (B) and the value of the electric current strength (i) on the current balance cause the value of laboratory gravitational acceleration (glab) to vary in the transfer of electric charge (q) according to coil type. The magnitude of the earth’s gravitational acceleration value obtained in a laboratory with a current balance for each type of coil is as follows: SF-37 glab-nr=9.89 m/s2, SF-38 glab-nr=9.90 m/s2, SF-39 glab-nr=9.76 m/s2, SF-40 glab-nr=9.95 m/s2, SF-41 glab-nr=9.75 m/s2 dan SF-42 glab-nr=9.93 m/s2. The results obtained indicate that the value of the earth’s gravitational acceleration in a laboratory close to the literature value is the value of the glab-nr in the SF-37 coil type of 9.89 m/s2.

scholarly journals Gamma rays in <i>L-B</i> coordinates at CORONAS-I altitude

2005 ◽  
Vol 23 (6) ◽  
pp. 2239-2247
Author(s):  
R. Bučík ◽  
K. Kudela ◽  
S. N. Kuznetsov ◽  
I. N. Myagkova
Keyword(s):  
Gamma Rays ◽  
Gamma Ray ◽  
Energetic Particles ◽  
Trapping Region ◽  
Trapped Particles ◽  
Longitudinal Variations ◽  
Energy Domain ◽  
Radiation Zone ◽  
Polar Orbiting Satellite ◽  
Bremsstrahlung Process

Abstract. We present here observations of gamma rays in the energy range between 3.0 and 8.3 MeV gathered by the SONG instrument aboard low-altitude polar-orbiting satellite CORONAS-I throughout the period March-June 1994. We concentrate on the emissions related to the trapped particles and organize CORONAS-I measurements in the magnetic L–B coordinate system. The spatial distribution of the average gamma-ray counts reveals that the most intense fluxes were observed under the inner radiation belt, at L<2, and that they are exclusively confined into the region of stably trapped particles, where daughter gamma rays could result from the interactions within the spacecraft and instrumental matter. In the outer radiation zone (L~4), the enhanced gamma radiation, also detected outside the stably trapping region, shows pronounced longitudinal variations. The observed eastward increase in the gamma-ray count rate suggests quasi-traped energetic (megavolt) electrons as a source of the gamma rays both in the upper atmosphere and in the satellite matter, most likely, through the bremsstrahlung process in the studied energy domain. Keywords. Magnetospheric physics (Energetic particles, precipitating; Energetic particles, trapped; Magnetosphereionosphere interactions)

Scattering of a discrete soliton by impurity in dipolar Bose–Einstein condensates

2014 ◽  
Vol 28 (30) ◽  
pp. 1450214 ◽  
Author(s):  
S. M. Al-Marzoug
Keyword(s):  
Center Of Mass ◽  
Dipole Interaction ◽  
Einstein Condensate ◽  
Mass Motion ◽  
Trapping Region ◽  
Discrete Soliton ◽  
Bose Einstein Condensate ◽  
Trapping Regions ◽  
Transmission Resonances ◽  
Bose Einstein

Scattering of a discrete soliton by a single impurity in dipolar Bose–Einstein condensate is investigated numerically. The results show that the increase of the strength of dipolar interactions leads to repeated reflection, transmission and trapping regions due to energy exchange between the center of mass motion and the internal modes of the impurity. However, increasing the strength of the attractive nonlocal dipole–dipole interaction will result in different scattering windows. While the dipole–dipole interaction can significantly expand the trapping region of the system, nevertheless transmission resonances through the impurity are still observed.

scholarly journals Degradation of Spacecraft Materials in the Space Environment

MRS Bulletin ◽  
2010 ◽  
Vol 35 (1) ◽  
pp. 20-24 ◽  
Author(s):  
Sharon K.R. Miller ◽  
Bruce Banks
Keyword(s):  
Power Generation ◽  
Atomic Oxygen ◽  
Control Structure ◽  
Charged Particles ◽  
Thermal Control ◽  
Space Environment ◽  
Temperature Extremes ◽  
The Earth ◽  
Materials Used ◽  
Space Data

AbstractWhen we think of space, we typically think of a vacuum containing very little matter that lies between the Earth and other planetary and stellar bodies. However, the space above Earth's breathable atmosphere and beyond contains many things that make designing durable spacecraft a challenge. Depending on where the spacecraft is flying, it may encounter atomic oxygen, ultraviolet and other forms of radiation, charged particles, micrometeoroids and debris, and temperature extremes. These environments on their own and in combination can cause degradation and failure of polymers, composites, paints and other materials used on the exterior of spacecraft for thermal control, structure, and power generation. This article briefly discusses and gives examples of some of the degradation experienced on spacecraft and flight experiments as a result of the space environment and the use of ground and space data to predict durability.

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