Time Evolution of Plasma Parameters during the Rise of a Solar Prominence Instability

Orozco Suárez, D.; Díaz, A. J.; Asensio Ramos, A.; Trujillo Bueno, J.
Referencia bibliográfica

The Astrophysical Journal Letters, Volume 785, Issue 1, article id. L10, 6 pp. (2014).

Fecha de publicación:
4
2014
Número de autores
4
Número de autores del IAC
3
Número de citas
13
Número de citas referidas
11
Descripción
We present high-spatial resolution spectropolarimetric observations of a quiescent hedgerow prominence taken in the He I 1083.0 nm triplet. The observation consisted of a time series in sit-and-stare mode of ~36 minutes duration. The spectrograph's slit crossed the prominence body and we recorded the time evolution of individual vertical threads. Eventually, we observed the development of a dark Rayleigh-Taylor plume that propagated upward with a velocity, projected onto the plane of the sky, of 17 km s–1. Interestingly, the plume apex collided with the prominence threads pushing them aside. We inferred Doppler shifts, Doppler widths, and magnetic field strength variations by interpreting the He I Stokes profiles with the HAZEL code. The Doppler shifts show that clusters of threads move coherently while individual threads have oscillatory patterns. Regarding the plume we found strong redshifts (~9-12 km s–1) and large Doppler widths (~10 km s–1) at the plume apex when it passed through the prominence body and before it disintegrated. We associate the redshifts with perspective effects while the Doppler widths are more likely due to an increase in the local temperature. No local variations of the magnetic field strength associated with the passage of the plume were found; this leads us to conclude that the plumes are no more magnetized than the surroundings. Finally, we found that some of the threads' oscillations are locally damped, what allowed us to apply prominence seismology techniques to infer additional prominence physical parameters.
Proyectos relacionados
Project Image
Magnetismo, Polarización y Transferencia Radiativa en Astrofísica
Los campos magnéticos están presentes en todos los plasmas astrofísicos y controlan la mayor parte de la variabilidad que se observa en el Universo a escalas temporales intermedias. Se encuentran en estrellas, a lo largo de todo el diagrama de Hertzsprung-Russell, en galaxias, e incluso quizás en el medio intergaláctico. La polarización de la luz
Tanausú del
Pino Alemán