First Imaging Observation of Standing Slow Wave in Coronal Fan Loops

Pant, Vaibhav, Tiwari, Ajay, Ding, Yuan and Banerjee, Dipankar (2017) First Imaging Observation of Standing Slow Wave in Coronal Fan Loops. The Astrophysical Journal Letters, 847. L5. ISSN 2041-8205

[img] Text (Full text)
Pant et al - First Imaging Observation of Standing Slow Wave in Coronal Fan Loops.pdf - Accepted Version
Restricted to Repository staff only until 14 September 2018.

Download (1MB)
Official URL:


We observe intensity oscillations along coronal fan loops associated with the active region AR 11428. The intensity oscillations were triggered by blast waves that were generated due to X-class flares in the distant active region AR 11429. To characterize the nature of oscillations, we created time–distance maps along the fan loops and noted that the intensity oscillations at two ends of the loops were out of phase. As we move along the fan loop, the amplitude of the oscillations first decreased and then increased. The out-of-phase nature together with the amplitude variation along the loop implies that these oscillations are very likely to be standing waves. The period of the oscillations is estimated to be ~27 minutes, damping time to be ~45 minutes, and phase velocity projected in the plane of sky to be ~65–83 km s−1. The projected phase speeds were in the range of the acoustic speed of coronal plasma at about 0.6 MK, which further indicates that these are slow waves. To the best of our knowledge, this is the first report on the existence of the standing slow waves in non-flaring fan loops.

Item Type: Article
Uncontrolled Keywords: Sun: corona, Sun: oscillations, Sun: UV radiation
Subjects: F500 Astronomy
Department: Faculties > Engineering and Environment > Mathematics, Physics and Electrical Engineering
Depositing User: Ajay Tiwari
Date Deposited: 28 Mar 2018 15:03
Last Modified: 05 May 2018 00:14

Actions (login required)

View Item View Item


Downloads per month over past year

View more statistics

Policies: NRL Policies | NRL University Deposit Policy | NRL Deposit Licence