Hi friends, just to inform you about a paper accepted for publication on ApJ Letters: short heat pulses can trigger strong plasma sloshing in coronal loops. This provides a new key to interpret possible oscillations in light curves. Thank you for your attention Fabio Reale
https://arxiv.org/abs/1607.01329 https://arxiv.org/abs/1607.01329
Plasma sloshing in pulse-heated solar and stellar coronal loops
Astrophysics > Solar and Stellar Astrophysics
F. Reale </find/astro-ph/1/au:+Reale_F/0/1/0/all/0/1> (Submitted on 5 Jul 2016)
There is evidence that coronal heating is highly intermittent, and flares are the high energy extreme. The properties of the heat pulses are difficult to constrain. Here hydrodynamic loop modeling shows that several large amplitude oscillations (~ 20% in density) are triggered in flare light curves if the duration of the heat pulse is shorter that the sound crossing time of the flaring loop. The reason is that the plasma has not enough time to reach pressure equilibrium during the heating and traveling pressure fronts develop. The period is a few minutes for typical solar coronal loops, dictated by the sound crossing time in the decay phase. The long period and large amplitude make these oscillations different from typical MHD waves. This diagnostic can be applied both to observations of solar and stellar flares and to future observations of non-flaring loops at high resolution. Submission history
From: Fabio Reale [view email https://arxiv.org/show-email/423ef955/1607.01329] [v1] Tue, 5 Jul 2016 17:02:27 GMT (341kb)
Hi Fabio,
Thanks for the interesting paper. Attached is a paper where we did something similar, using multiple loops to simulate a flare. We speculated that the collision of density fronts could be the reason for loop-top bars of emission that are sometimes seen in the EUV in two-ribbon flares, though, as you point out, that scenario requires some symmetry.
The nanoflare connection is interesting too, and definitely has implications for the next generation of instrumentation!
Best regards,
Kathy
On Jul 6, 2016, at 6:02 AM, Fabio Reale reale@astropa.unipa.it wrote:
Hi friends, just to inform you about a paper accepted for publication on ApJ Letters: short heat pulses can trigger strong plasma sloshing in coronal loops. This provides a new key to interpret possible oscillations in light curves. Thank you for your attention Fabio Reale
https://arxiv.org/abs/1607.01329 https://arxiv.org/abs/1607.01329
Plasma sloshing in pulse-heated solar and stellar coronal loops
Astrophysics > Solar and Stellar Astrophysics
F. Reale </find/astro-ph/1/au:+Reale_F/0/1/0/all/0/1> (Submitted on 5 Jul 2016)
There is evidence that coronal heating is highly intermittent, and flares are the high energy extreme. The properties of the heat pulses are difficult to constrain. Here hydrodynamic loop modeling shows that several large amplitude oscillations (~ 20% in density) are triggered in flare light curves if the duration of the heat pulse is shorter that the sound crossing time of the flaring loop. The reason is that the plasma has not enough time to reach pressure equilibrium during the heating and traveling pressure fronts develop. The period is a few minutes for typical solar coronal loops, dictated by the sound crossing time in the decay phase. The long period and large amplitude make these oscillations different from typical MHD waves. This diagnostic can be applied both to observations of solar and stellar flares and to future observations of non-flaring loops at high resolution. Submission history
From: Fabio Reale [view email https://arxiv.org/show-email/423ef955/1607.01329] [v1] Tue, 5 Jul 2016 17:02:27 GMT (341kb)
Loops mailing list Loops@solar.physics.montana.edu https://mithra.physics.montana.edu/mailman/listinfo/loops
loops@solar.physics.montana.edu