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Radiation Emitted by Relativistic and Non-relativistic Moving Particles
Published in V. L. Ginzburg, Oleg Glebov, Applications of Electrodynamics in Theoretical Physics and Astrophysics, 2017
The radiation emitted by a nonrelativistic electron moving in a magnetic field is often referred to as “cyclotron radiation”. (The terms describing the radiation emitted by charges moving in magnetic fields have not yet been fully agreed upon. In our opinion we must use the already existing terms and call such radiation in the general case “magneto-bremsstrahlung radiation”, in the case of nonrelativistic particles “cyclotron radiation”, and in the case of highly relativistic particles “synchrotron radiation”. Thus, with this nomenclature, cyclotron and synchrotron radiation are the limiting special cases corresponding respectively to the nonrelativistic or weakly relativistic case and to the highly relativistic case.) The frequency of the cyclotron radiation (the dipole radiation) is of course equal to the frequency of electron rotation in the field ℋ0, i.e. () ωH=eH0mc=1.76×107H0.
Particles and Radiation
Published in Rob Appleby, Graeme Burt, James Clarke, Hywel Owen, The Science and Technology of Particle Accelerators, 2020
Rob Appleby, Graeme Burt, James Clarke, Hywel Owen
We saw that cyclotron radiation is the electromagnetic radiation emitted by non-relativistic charges deflected by moving through a magnetic field – often in a circular path. Synchrotron radiation is the equivalent process, but for when the charges are moving relativistically (γ≫1). In the previous section we saw that relativity modifies the formula for the cyclotron frequency; it also greatly changes the pattern and strength of the emitted radiation.
Recent Trends in Plasma Chemistry and Spectroscopy Diagnostics
Published in Tanmoy Chakraborty, Lalita Ledwani, Research Methodology in Chemical Sciences, 2017
There are basically three types of radiation processes in unmagnetized plasmas, namely, bound–bound or line radiation, free–bound or continuum radiation, and free–free or Bremsstrahlung radiations. Cyclotron radiation, which occurs in magnetized plasmas, is due to magnetic centripetal acceleration of charge particles as they spiral about the magnetic field lines. Blackbody radiation emitted from plasma in thermodynamic equilibrium is important only in astrophysical plasmas in view of the large size required for plasma to radiate as a black body.
Energy Confinement Dynamics and Some Properties of Plasma Self-Organization in ECRH Regime in the L-2M Stellarator
Published in Fusion Science and Technology, 2023
Aleksei Meshcheryakov, Irina Grishina
Let us consider the processes occurring in plasma in different phases of its confinement. Phase 1 is the phase of plasma initial heating. Plasma heating starts in the central region (region of resonance absorption of electron cyclotron radiation). Next, the boundary of the heated plasma region propagates from the center to the plasma edge. During the entire phase 1, the plasma layer near the separatrix remains cold, as evidenced by the absence of the floating potential signal from the Langmuir probe installed at a depth of 5 mm inside the plasma. Thus, in phase 1, the “detachment” regime is established, that is, the regime when plasma-wall interaction is negligible. The flux of charged particles from plasma onto the wall turns out to be insignificant. The smallness of the flux of charged particles is confirmed by the absence of floating potential on the limiter located outside the plasma (see Fig. 1). As a result, the power of the heat flux onto the wall due to diffusion turns out to be insignificant. Since there is a cold layer at the plasma edge, within which the plasma temperature and its gradients are small, the heat flux onto the wall due to heat conduction will also be insignificant. Therefore, in phase 1, total heat power loss Ploss is mainly determined by radiation loss Ploss ≈ Prad.
A Nodal Model for Tokamak Burning Plasma Space-Time Dynamics
Published in Fusion Science and Technology, 2021
These energetic alpha particles transfer their energy first preferentially to heat the core plasma electrons,1 and the heated electrons produce electron cyclotron radiation2–6 (ECR), some of which is reabsorbed in the plasma core and in other regions of the plasma (both before and after being reflected from the wall) and in the surrounding wall. Thus, ECR instantaneously transports this core energy to heat electrons in outer parts of the plasma and to heat the wall.2–6