Frequently Occurring Reconnection Jets from Sunspot Light Bridges

Hui Tian, Vasyl Yurchyshyn, Hardi Peter, Sami K. Solanki, Peter R. Young, Lei Ni, Wenda Cao, Kaifan Ji, Yingjie Zhu, Jingwen Zhang, Tanmoy Samanta, Yongliang Song, Jiansen He, Linghua Wang, Yajie Chen

Research output: Contribution to journalArticlepeer-review

38 Scopus citations

Abstract

Solid evidence of magnetic reconnection is rarely reported within sunspots, the darkest regions with the strongest magnetic fields and lowest temperatures in the solar atmosphere. Using the world's largest solar telescope, the 1.6 m Goode Solar Telescope, we detect prevalent reconnection through frequently occurring fine-scale jets in the Hα line wings at light bridges, the bright lanes that may divide the dark sunspot core into multiple parts. Many jets have an inverted Y-shape, shown by models to be typical of reconnection in a unipolar field environment. Simultaneous spectral imaging data from the Interface Region Imaging Spectrograph show that the reconnection drives bidirectional flows up to 200 km s-1, and that the weakly ionized plasma is heated by at least an order of magnitude up to ∼80,000 K. Such highly dynamic reconnection jets and efficient heating should be properly accounted for in future modeling efforts of sunspots. Our observations also reveal that the surge-like activity previously reported above light bridges in some chromospheric passbands such as the Hα core has two components: the ever-present short surges likely to be related to the upward leakage of magnetoacoustic waves from the photosphere, and the occasionally occurring long and fast surges that are obviously caused by the intermittent reconnection jets.

Original languageEnglish (US)
Article number92
JournalAstrophysical Journal
Volume854
Issue number2
DOIs
StatePublished - Feb 20 2018

All Science Journal Classification (ASJC) codes

  • Astronomy and Astrophysics
  • Space and Planetary Science

Keywords

  • Sun: UV radiation
  • Sun: chromosphere
  • Sun: transition region
  • magnetic reconnection
  • sunspots

Fingerprint

Dive into the research topics of 'Frequently Occurring Reconnection Jets from Sunspot Light Bridges'. Together they form a unique fingerprint.

Cite this