Energy confinement in the spherical tokamak Globus-M2 with a toroidal magnetic field reaching 0.8 T

Abstract The work presents the results of the energy confinement study carried out on the compact spherical tokamak (ST) Globus-M2 with toroidal magnetic field (BT) as high as 0.8 T. A reproducible and stable discharge was obtained with the average plasma density (5-10) 1019 m-3. Despite the increase in the magnetic field, the neutral beam injection (NBI) led to clear and reproducible transition to the H-mode accompanied by a decrease in the turbulence level at the plasma edge. NBI allowed effectively heat the plasma: electron and ion temperatures in the plasma core exceeded 1 keV. In comparison with the previous experiments carried out with BT=0.4 T plasma total stored energy was increased by a factor of 4. The main reason of this phenomenon is a strong dependence of the energy confinement time (τE) on the toroidal magnetic field in the spherical tokamak. It was experimentally confirmed that such kind of dependence is valid for ST with magnetic field up to 0.8 T. It also has been shown that the enhancement of the energy confinement in the Globus-M2 with collisionality decrease is associated with an improvement of both electron and ion heat transport.

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Dependence of energy confinement time on toroidal magnetic field in the TUMAN-3M tokamak

Technical Physics Letters ◽

10.1134/s1063785012040098 ◽

2012 ◽

Vol 38 (4) ◽

pp. 320-323

Author(s):

S. V. Lebedev ◽

L. G. Askinazi ◽

M. I. Vildjunas ◽

N. A. Zhubr ◽

V. A. Kornev ◽

...

Keyword(s):

Magnetic Field ◽

Toroidal Magnetic Field ◽

Confinement Time ◽

Energy Confinement ◽

Energy Confinement Time

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Влияние параллельного слоям магнитного поля на фототок в GaAs/AlAs p-i-n-структурах

Физика и техника полупроводников ◽

10.21883/ftp.2022.01.51820.9738 ◽

2022 ◽

Vol 56 (1) ◽

pp. 107

Author(s):

И.А. Ларкин ◽

Ю.Н. Ханин ◽

Е.Е. Вдовин

Keyword(s):

Magnetic Field ◽

Wavelength Range ◽

Strong Dependence ◽

Diffusion Current ◽

Radiation Wavelength ◽

Quantization Level ◽

Dimensional Quantization ◽

Field Parallel ◽

The Magnetic Field

The behavior of the photocurrent in GaAs / AlAs p-i-n heterostructures is studied in a magnetic field parallel to the heterolayers in the wavelength range from 395 to 650 nm. A strong dependence of the non-oscillating component of the photocurrent on the radiation wavelength associated with the suppression of the diffusion current by the magnetic field was found. It is shown that the behavior of the oscillating component of the photocurrent in a magnetic field does not depend on the wavelength of light and is determined by the transfer of electrons through the dimensional quantization level in a triangular near-barrier well. It is shown that the suppression of the oscillating component by the magnetic field is due to the smearing of the level in the triangular well due to the motion of electrons parallel to the walls of the well and perpendicular to the magnetic field.

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Fusion triple product increase in ten times in the compact spherical tokamak Globus-M2 due the doubling of the toroidal magnetic field

Nuclear Fusion ◽

10.1088/1741-4326/abe08c ◽

2021 ◽

Author(s):

Gleb Kurskiev ◽

Vasily K Gusev ◽

Nikolay Sakharov ◽

I M Balachenkov ◽

Nikolai Nikolaevich Bakharev ◽

...

Keyword(s):

Magnetic Field ◽

Triple Product ◽

Toroidal Magnetic Field ◽

Spherical Tokamak ◽

Product Increase

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Numerical study of toroidal magnetic field on the self-gravitating protoplanetary disks

International Journal of Modern Physics D ◽

10.1142/s0218271820500674 ◽

2020 ◽

Vol 29 (09) ◽

pp. 2050067

Author(s):

Hanifeh Ghanbarnejad ◽

Maryam Ghasemnezhad

Keyword(s):

Magnetic Field ◽

Accretion Disks ◽

Numerical Solutions ◽

Numerical Study ◽

Ohmic Heating ◽

The Self ◽

Toroidal Magnetic Field ◽

Heating Process ◽

Heating And Cooling ◽

The Magnetic Field

In this paper, we study the self-gravitating accretion disks by considering the toroidal component of magnetic field, [Formula: see text] and wind/outflow in the flow and also investigate the effect of two parameters, [Formula: see text] and [Formula: see text] corresponding to magnetic field on the latitudinal structure of such accretion disks. The cooling of the disk is parameterized simply as, [Formula: see text] (where [Formula: see text] is the internal energy and [Formula: see text] is the cooling timescale and [Formula: see text] is a free constant) and the heating rate is decomposed into two components, magnetic field and viscosity dissipations. We have shown that when the toroidal magnetic field becomes stronger, the heating process (viscous and resistivity) and the radiative cooling rate increase. Ohmic heating is much bigger than viscous heating and cooling, so we must consider the role of the magnetic field in the energy equation. Our numerical solutions show that the thickness of the disk decreases with strong toroidal component of magnetic field. The magnetic field leads to production of the outflow in the low latitude. So, by increasing the toroidal component of the magnetic field, the regions which belong to inflow decrease and the disk is cooled.

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Threshold speed for two-dimensional confinement of charged particles in certain axisymmetric magnetic fields

Canadian Journal of Physics ◽

10.1139/cjp-2017-0415 ◽

2018 ◽

Vol 96 (5) ◽

pp. 519-523 ◽

Cited By ~ 1

Author(s):

K. Kabin ◽

G. Kalugin ◽

E. Spanswick ◽

E. Donovan

Keyword(s):

Magnetic Field ◽

Power Law ◽

Critical Speed ◽

Longitudinal Magnetic Field ◽

Strong Dependence ◽

Charged Particles ◽

Transcendental Equation ◽

Power Exponent ◽

Magnetic Field Magnitude ◽

The Magnetic Field

In this paper we discuss conditions under which charged particles are confined by an axisymmetric longitudinal magnetic field with power law dependence on the radius. We derive a transcendental equation for the critical speed corresponding to the threshold between bounded and unbounded trajectories of the particles. This threshold speed shows strong dependence on the direction, and this dependence becomes more prominent as the exponent of the power law increases. The equation for threshold speed can be solved exactly for several specific values of the power exponent, but in general it requires a numerical treatment. Remarkably, if the magnetic field magnitude decreases more slowly than the inverse of the radius, charged particles remain confined no matter how large their energies may be.

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MAGNETIC FLUX SENSITIVITY OF THE POPULATION AND THE PANCHARATNAM PHASE FOR A SINGLE COOPER-PAIR BOX

International Journal of Quantum Information ◽

10.1142/s0219749911007459 ◽

2011 ◽

Vol 09 (03) ◽

pp. 883-892 ◽

Cited By ~ 1

Author(s):

M. A. BOUCHENE ◽

M. ABDEL-ATY

Keyword(s):

Magnetic Field ◽

Magnetic Flux ◽

Cooper Pair ◽

Strong Dependence ◽

Pancharatnam Phase ◽

Cooper Pair Box ◽

Squid Loop ◽

The Magnetic Field ◽

Excitation Parameters ◽

Sensitive Method

We study the behaviour of a single Cooper-pair box with a SQUID loop interacting with a magnetic field. We demonstrate the strong dependence of the population and the Pancharatnam phase on the magnetic flux and study the modifications when a temporal drift is present on the magnetic field. Moreover, we show that the Pancharatnam phase is more sensitive to the excitation parameters than the populations, suggesting a sensitive method for controlling the system and/or detecting flux variations.

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Internal Rotation of AB Doradus

Symposium - International Astronomical Union ◽

10.1017/s0074180900163272 ◽

2000 ◽

Vol 195 ◽

pp. 399-400

Author(s):

K. M. Hiremath

Keyword(s):

Magnetic Field ◽

Internal Rotation ◽

Rotation Velocity ◽

Toroidal Magnetic Field ◽

Mhd Equations ◽

Time Dependent ◽

Convective Envelope ◽

Dependent Part ◽

The Magnetic Field

Using Chandrasekhar's MHD equations, we solve for the steady part of the internal rotation of AB Doradus. We estimate the size of the convective envelope to be ~ 40% of the radius and the rotation velocity at the base to be not less than 1.42 × 10−4 rad/sec. This study also yields the steady part of the toroidal magnetic field which is distributed throughout the convective envelope. We present rotational and toroidal magnetic field profiles in the interior and conjecture on the time-dependent part of the magnetic field.

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