Is the mechanism of solar flares on red dwarfs and brown dwarfs the same as that on the Sun?

2018-10-23 09:33:40

The Sun has solar flares that are caused when there is a magnetic reconnection in the Sun's atmosphere, causing a loop of magnetic field to be ejected at high energy, along with a large number of protons, giving a intense burst of radiation.

Other stars - notably some red dwarfs - have much more intense flares than the Sun does. Is the mechanism the same in these stars as in the Sun, and in larger stars? What causes the flares in red dwarfs, and even brown dwarfs? Why do less powerful stars have more powerful flares?

Jupiter also has a magnetic field, and it's magnetosphere is composed of plasmas. Why aren't "Jovian Flares" seen?

Related: How do large solar flares compare to flares on other stars?

Yes, the basic mechanism is thought to be the same on red dwarfs and at least the hotter brown dwarfs, but the details can be different.

As you say, magnetic reconnection in the corona is the starting point. Well, actually it is fluid motions at the magnetic loop footp

  • Yes, the basic mechanism is thought to be the same on red dwarfs and at least the hotter brown dwarfs, but the details can be different.

    As you say, magnetic reconnection in the corona is the starting point. Well, actually it is fluid motions at the magnetic loop footpoints that is the starting point. The B-field and partially ionised plasma are coupled and photospheric motions put (magnetic) potential energy into the B-field structures.

    This potential energy can be released suddenly in reconnection events. These can drive coronal mass ejections or accelerate charged particles along the loop field lines.

    A flare occurs when a significant amount of energy goes into accelerating charged particles down the field lines towards the loop footpoints. These charge particles emit radio waves and then non-thermal hard X-rays as they impact the thicker chromosphere/photosphere. Their energy is then thermalised, heating the chromosphere and possibly causing hot ($>10^{6}$ K) material to evapo

    2018-10-23 09:41:39