All Questions
6 questions
4
votes
2
answers
118
views
Plage regions data
Plages are phenomena of stellar activity.
Where can I find openly-accessible data of plage regions of the Sun with other parameters such as faculae region, magnetic field, etc?
- 193
2
votes
1
answer
64
views
Interaction of supersonic wind with static Inter-Stellar Medium (ISM)
Recently I was studying about the interaction of supersonic flow (wind) with a slowly flowing medium. In a paper by Dyson, Falle, and Perry 1980 MNRAS stated that when a supersonic wind impinged upon ...
- 97
2
votes
1
answer
88
views
What is the most efficient particle acceleration mechanism in space and astrophysical plasmas
My question is:
What are the most efficient particle acceleration mechanisms in space and astrophysical plasmas: wave-particle interactions, collisionless shocks, or magnetic reconnection?
Does it ...
- 490
2
votes
1
answer
71
views
Derivation of average momentum change in diffusive shock acceleration
I am trying to figure out a specific step in the derivation of the power law spectrum for cosmic ray particles upon diffusive shock acceleration. I am working with Drury 1983 (pdf link) but I have ...
- 21
1
vote
1
answer
178
views
Bulk viscosity in jump conditions for shock waves
One of the jump conditions for shock waves can be derived from the Navier-Stokes equation and it takes the form (see Shu, Gas dynamics, p.212)
$\dfrac{d}{dx}\left(\rho u^2 + P - \frac{4}{3}\mu \frac{...
- 111
3
votes
2
answers
724
views
A question about the Fermi acceleration
In high school physics, we know that a charged particle cannot gain energy from a magnetic field. But, it seems that in the so-called Fermi acceleration, the particle is accelerated by the magnetic ...
- 1,075