Bibcode
Kubo, M.; Katsukawa, Y.; Suematsu, Y.; Kano, R.; Bando, T.; Narukage, N.; Ishikawa, R.; Hara, H.; Giono, G.; Tsuneta, S.; Ishikawa, S.; Shimizu, T.; Sakao, T.; Winebarger, A.; Kobayashi, K.; Cirtain, J.; Champey, P.; Auchère, F.; Trujillo Bueno, J.; Asensio Ramos, A.; Štěpán, J.; Belluzzi, L.; Manso Sainz, R.; De Pontieu, B.; Ichimoto, K.; Carlsson, M.; Casini, R.; Goto, M.
Bibliographical reference
The Astrophysical Journal, Volume 832, Issue 2, article id. 141, 9 pp. (2016).
Advertised on:
12
2016
Journal
Citations
20
Refereed citations
20
Description
High-cadence observations by the slit-jaw (SJ) optics system of the
sounding rocket experiment known as the Chromospheric Lyman Alpha
Spectropolarimeter (CLASP) reveal ubiquitous intensity disturbances that
recurrently propagate in either the chromosphere or the transition
region or both at a speed much higher than the speed of sound. The
CLASP/SJ instrument provides a time series of two-dimensional images
taken with broadband filters centered on the Lyα line at a 0.6 s
cadence. The multiple fast-propagating intensity disturbances appear in
the quiet Sun and in an active region, and they are clearly detected in
at least 20 areas in a field of view of 527″ × 527″
during the 5 minute observing time. The apparent speeds of the intensity
disturbances range from 150 to 350 km s-1, and they are
comparable to the local Alfvén speed in the transition region.
The intensity disturbances tend to propagate along bright elongated
structures away from areas with strong photospheric magnetic fields.
This suggests that the observed fast-propagating intensity disturbances
are related to the magnetic canopy structures. The maximum distance
traveled by the intensity disturbances is about 10″, and the
widths are a few arcseconds, which are almost determined by a pixel size
of 1.″03. The timescale of each intensity pulse is shorter than 30
s. One possible explanation for the fast-propagating intensity
disturbances observed by CLASP is magnetohydrodynamic fast-mode waves.