A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active Region
Coronal loop oscillations are common phenomena in the solar corona, which are often classified as decaying and decayless oscillations. Using the high-resolution observation measured by the Extreme Ultraviolet Imager (EUI) on board the Solar Orbiter, we statistically investigate small-scale transvers...
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| Format: | Article |
| Language: | English |
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IOP Publishing
2023-01-01
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| Series: | The Astrophysical Journal |
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| Online Access: | https://doi.org/10.3847/1538-4357/acacf4 |
| _version_ | 1797697251960684544 |
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| author | Dong Li David M. Long |
| author_facet | Dong Li David M. Long |
| author_sort | Dong Li |
| collection | DOAJ |
| description | Coronal loop oscillations are common phenomena in the solar corona, which are often classified as decaying and decayless oscillations. Using the high-resolution observation measured by the Extreme Ultraviolet Imager (EUI) on board the Solar Orbiter, we statistically investigate small-scale transverse oscillations with short periods (<200 s) of coronal loops in an active region (AR), i.e., NOAA AR 12965. A total of 111 coronal loops are identified in EUI 174 Å images, and they all reveal transverse oscillations without any significant decaying, regarded as decayless oscillations. Oscillatory periods are measured from ∼11 to ∼185 s, with a median period of 40 s. Thus, they are also termed short-period oscillations. The corresponding loop lengths are measured from ∼10.5 to ∼30.2 Mm, and a strong dependence of oscillatory periods on loop lengths is established, indicating that the short-period oscillations are standing kink-mode waves in nature. Based on the coronal seismology, kink speeds are measured to be ∼330–1910 km s ^−1 , and magnetic field strengths in coronal loops are estimated to be ∼4.1–25.2 G, while the energy flux carried by decayless kink oscillations lies in the range from roughly 7 to 9220 W m ^−2 . Our estimations suggest that the wave energy carried by short-period decayless kink oscillations cannot support the coronal heating in the AR. |
| first_indexed | 2024-03-12T03:37:40Z |
| format | Article |
| id | doaj.art-5358c180e500471a8a572a79abe58b83 |
| institution | Directory Open Access Journal |
| issn | 1538-4357 |
| language | English |
| last_indexed | 2024-03-12T03:37:40Z |
| publishDate | 2023-01-01 |
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| spelling | doaj.art-5358c180e500471a8a572a79abe58b832023-09-03T13:07:51ZengIOP PublishingThe Astrophysical Journal1538-43572023-01-019441810.3847/1538-4357/acacf4A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active RegionDong Li0https://orcid.org/0000-0002-4538-9350David M. Long1https://orcid.org/0000-0003-3137-0277Purple Mountain Observatory, Chinese Academy of Sciences , Nanjing 210023, People’s Republic of China ; lidong@pmo.ac.cnUCL-Mullard Space Science Laboratory , Holmbury House, Holmbury St. Mary, Dorking, Surrey, RH5 6NT, UKCoronal loop oscillations are common phenomena in the solar corona, which are often classified as decaying and decayless oscillations. Using the high-resolution observation measured by the Extreme Ultraviolet Imager (EUI) on board the Solar Orbiter, we statistically investigate small-scale transverse oscillations with short periods (<200 s) of coronal loops in an active region (AR), i.e., NOAA AR 12965. A total of 111 coronal loops are identified in EUI 174 Å images, and they all reveal transverse oscillations without any significant decaying, regarded as decayless oscillations. Oscillatory periods are measured from ∼11 to ∼185 s, with a median period of 40 s. Thus, they are also termed short-period oscillations. The corresponding loop lengths are measured from ∼10.5 to ∼30.2 Mm, and a strong dependence of oscillatory periods on loop lengths is established, indicating that the short-period oscillations are standing kink-mode waves in nature. Based on the coronal seismology, kink speeds are measured to be ∼330–1910 km s ^−1 , and magnetic field strengths in coronal loops are estimated to be ∼4.1–25.2 G, while the energy flux carried by decayless kink oscillations lies in the range from roughly 7 to 9220 W m ^−2 . Our estimations suggest that the wave energy carried by short-period decayless kink oscillations cannot support the coronal heating in the AR.https://doi.org/10.3847/1538-4357/acacf4Solar ultraviolet emissionSolar oscillationsMagnetohydrodynamicsSolar coronal seismologySolar coronal loops |
| spellingShingle | Dong Li David M. Long A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active Region The Astrophysical Journal Solar ultraviolet emission Solar oscillations Magnetohydrodynamics Solar coronal seismology Solar coronal loops |
| title | A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active Region |
| title_full | A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active Region |
| title_fullStr | A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active Region |
| title_full_unstemmed | A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active Region |
| title_short | A Statistical Study of Short-period Decayless Oscillations of Coronal Loops in an Active Region |
| title_sort | statistical study of short period decayless oscillations of coronal loops in an active region |
| topic | Solar ultraviolet emission Solar oscillations Magnetohydrodynamics Solar coronal seismology Solar coronal loops |
| url | https://doi.org/10.3847/1538-4357/acacf4 |
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