000005652 001__ 5652
000005652 005__ 20220131113619.0
000005652 0247_ $$2DOI$$a 10.3847/2041-8213/ac3007
000005652 037__ $$aSCART-2022-0033
000005652 100__ $$aPanesar, Navdeep K.
000005652 245__ $$aThe Magnetic Origin of Solar Campfires
000005652 260__ $$c2021
000005652 520__ $$aSolar campfires are fine-scale heating events, recently observed by Extreme Ultraviolet Imager (EUI) on board Solar Orbiter. Here we use EUI 174 Å images, together with EUV images from Solar Dynamics Observatory (SDO)/Atmospheric Imaging Assembly (AIA), and line-of-sight magnetograms from SDO/Helioseismic and Magnetic Imager (HMI) to investigate the magnetic origin of 52 randomly selected campfires in the quiet solar corona. We find that (i) the campfires are rooted at the edges of photospheric magnetic network lanes; (ii) most of the campfires reside above the neutral line between majority-polarity magnetic flux patch and a merging minority-polarity flux patch, with a flux cancelation rate of ~1018 Mx hr-1; (iii) some of the campfires occur repeatedly from the same neutral line; (iv) in the large majority of instances, campfires are preceded by a cool-plasma structure, analogous to minifilaments in coronal jets; and (v) although many campfires have "complex" structure, most campfires resemble small-scale jets, dots, or loops. Thus, "campfire" is a general term that includes different types of small-scale solar dynamic features. They contain sufficient magnetic energy (~1026-1027 erg) to heat the solar atmosphere locally to 0.5-2.5 MK. Their lifetimes range from about 1 minute to over 1 hr, with most of the campfires having a lifetime of <10 minutes. The average lengths and widths of the campfires are 5400 ± 2500 km and 1600 ± 640 km, respectively. Our observations suggest that (a) the presence of magnetic flux ropes may be ubiquitous in the solar atmosphere and not limited to coronal jets and larger-scale eruptions that make CMEs, and (b) magnetic flux cancelation is the fundamental process for the formation and triggering of most campfires.
000005652 594__ $$aSTCE
000005652 6531_ $$aSolar Orbiter
000005652 6531_ $$aEUI
000005652 700__ $$aTiwari, Sanjiv K.
000005652 700__ $$aBerghmans, David
000005652 700__ $$aCheung, Mark C. M.
000005652 700__ $$aMüller, Daniel
000005652 700__ $$aAuchere, Frederic
000005652 700__ $$aZhukov, Andrei
000005652 773__ $$n1, id.L20$$pThe Astrophysical Journal Letters$$v921$$y2021
000005652 8560_ $$fdavid.berghmans@observatoire.be
000005652 85642 $$ahttps://ui.adsabs.harvard.edu/abs/2021ApJ...921L..20P/abstract
000005652 905__ $$apublished in
000005652 980__ $$aREFERD