190 likes | 368 Views
Physics 777 Plasma Physics and Magnetohydrodynamics (MHD). Instructor: Gregory Fleishman Lecture 5. Microscopic Emission Processes in the Plasma. 07 October 200 8. Plan of the Lecture. Vavilov-Cherenkov radiation Bremsstrahlung Diffusive radiations Magnetobremsstrahlung
E N D
Physics 777Plasma Physics and Magnetohydrodynamics (MHD) Instructor: Gregory Fleishman Lecture 5. Microscopic Emission Processes in the Plasma 07 October 2008
Plan of the Lecture • Vavilov-Cherenkov radiation • Bremsstrahlung • Diffusive radiations • Magnetobremsstrahlung • Transition radiation
Section 1. Vavilov-Cherenkov radiation (N.P. 1958) For simplicity:
Section 3. Diffusive radiations Consider first the radiation in the presence of random magnetic field: Diffusive Synchrotron Radiation (DSR)
If Diffusive Radiation in Langmuir Waves (DRL)
General case Cyclotron Emission
Section 6. Homework • Homework from Lecture 4. • Written report topic (WRT) # 1. Assume stochastic acceleration at the loop top with a power-law spectrum of magnetic turbulence. Calculate the DSR spectrum from electrons with different non-relativistic energies. • WRT # 2. Assume a power-law spectrum for Langmuir wave ensemble and some number (Ax1033) of relativistic electrons with the Lorenz factor 10. Calculate the DRL spectrum. • WRT # 3. Calculate synchrotron emission from warm and hot components of the interstellar medium. Calculate and plot these contribution together for different filling factors. • WRT # 4. Assume sinusoidal oscillations of the transverse magnetic field component. Calculate modulation amplitude (or power), phase, and degree of polarization as a function of frequency. • WRT # 5. Assume that the particle trapping at the Masuda source is provided by scattering of the electrons by magnetic inhomogeneities with a power-law spectrum. Calculate the DSR produced by the electrons generating the above-the-loop-top hard X-ray emission (i.e., take the electron spectrum from the corresponding papers). • For all WRT: outline the introduction for the written report. Use Latex, e.g., ApJ style (preferable).