Indian Institute of Technology Guwahati
Question
Asked 14th Feb, 2022
Could magnetic fields within an accretion disk affect the temperature of the disk?
We all know that accretion disks around BHs are presumably be magnetized in nature. If we consider ideal MHD, we know magnetic fields are frozen within the plasmas. Now, magnetic fields are turbulent, so can they help in raising the temperature of the disk? And is it significant?
Most recent answer
Charles Ivie, Thanks for the answer. Yes, the flow seems to behave as a two-temperature flow due to the different coupling between electrons and ions. But It is not very clear how magnetic fields affect them generating the anisotropy in temperature?
All Answers (5)
Savitribai Phule Pune University
hi,
By thumb rule and as the magnetic fields are turbulent, formation of local pinching effects in the magnetic fields trapped inside the plasmas could in principle elevate the temperature of that region.
Regards
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Retired
The Boltzmann interpretation of temperature is that it is related to particle velocity. Considering that many of the particles in an accretion disk are expected to be electrically charged the magnetic field would be expected to cause a geometrically anisotropic distribution of temperature and associated thermal effects. This obviously complicates analysis of the thermal profile.
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Airports Authority of India
Samik Mitra@
Answer is YES. Magnetic field in the accretion disk can definitely produce temperature.Accretion disk means it may may be around neutron star, pulsar, magnetar, BH, Local bubble , sun , etc
Indian Institute of Technology Guwahati
Charles Ivie, Thanks for the answer. Yes, the flow seems to possibly behave as a two-temperature flow, which is due to the different coupling between electrons and ions. But It is not very clear how magnetic fields affect them generating the anisotropy?
Indian Institute of Technology Guwahati
Charles Ivie, Thanks for the answer. Yes, the flow seems to behave as a two-temperature flow due to the different coupling between electrons and ions. But It is not very clear how magnetic fields affect them generating the anisotropy in temperature?
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