skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: KINEMATICS AND FINE STRUCTURE OF AN UNWINDING POLAR JET OBSERVED BY THE SOLAR DYNAMIC OBSERVATORY/ATMOSPHERIC IMAGING ASSEMBLY

Abstract

We present an observational study of the kinematics and fine structure of an unwinding polar jet, with high temporal and spatial observations taken by the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory and the Solar Magnetic Activity Research Telescope. During the rising period, the shape of the jet resembled a cylinder with helical structures on the surface, while the mass of the jet was mainly distributed on the cylinder's shell. In the radial direction, the jet expanded successively at its western side and underwent three distinct phases: the gradually expanding phase, the fast expanding phase, and the steady phase. Each phase lasted for about 12 minutes. The angular speed of the unwinding motion of the jet and the twist transferred into the outer corona during the eruption are estimated to be 11.1 x 10{sup -3} rad s{sup -1} (period = 564 s) and 1.17-2.55 turns (or 2.34-5.1{pi}), respectively. On the other hand, by calculating the azimuthal component of the magnetic field in the jet and comparing the free energy stored in the non-potential magnetic field with the jet's total energy, we find that the non-potential magnetic field in the jet is enough to supply the energy for themore » ejection. These new observational results strongly support the scenario that the jets are driven by the magnetic twist, which is stored in the twisted closed field of a small bipole, and released through magnetic reconnection between the bipole and its ambient open field.« less

Authors:
;  [1];  [2];  [3]
  1. National Astronomical Observatories/Yunnan Observatory, Chinese Academy of Sciences, Kunming 650011 (China)
  2. Key Laboratory of Solar Activity, National Astronomical Observatories, Chinese Academy of Science, Beijing 100012 (China)
  3. Physics and Astronomy Department, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia)
Publication Date:
OSTI Identifier:
21562547
Resource Type:
Journal Article
Journal Name:
Astrophysical Journal Letters
Additional Journal Information:
Journal Volume: 735; Journal Issue: 2; Other Information: DOI: 10.1088/2041-8205/735/2/L43; Journal ID: ISSN 2041-8205
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CHROMOSPHERE; FINE STRUCTURE; FREE ENERGY; JETS; MAGNETIC FIELDS; MAGNETIC RECONNECTION; SOLAR CORONA; ATMOSPHERES; ENERGY; PHYSICAL PROPERTIES; SOLAR ATMOSPHERE; STELLAR ATMOSPHERES; STELLAR CORONAE; THERMODYNAMIC PROPERTIES

Citation Formats

Shen Yuandeng, Liu Yu, Su Jiangtao, and Ibrahim, Ahmed, E-mail: ydshen@ynao.ac.cn. KINEMATICS AND FINE STRUCTURE OF AN UNWINDING POLAR JET OBSERVED BY THE SOLAR DYNAMIC OBSERVATORY/ATMOSPHERIC IMAGING ASSEMBLY. United States: N. p., 2011. Web. doi:10.1088/2041-8205/735/2/L43.
Shen Yuandeng, Liu Yu, Su Jiangtao, & Ibrahim, Ahmed, E-mail: ydshen@ynao.ac.cn. KINEMATICS AND FINE STRUCTURE OF AN UNWINDING POLAR JET OBSERVED BY THE SOLAR DYNAMIC OBSERVATORY/ATMOSPHERIC IMAGING ASSEMBLY. United States. doi:10.1088/2041-8205/735/2/L43.
Shen Yuandeng, Liu Yu, Su Jiangtao, and Ibrahim, Ahmed, E-mail: ydshen@ynao.ac.cn. Sun . "KINEMATICS AND FINE STRUCTURE OF AN UNWINDING POLAR JET OBSERVED BY THE SOLAR DYNAMIC OBSERVATORY/ATMOSPHERIC IMAGING ASSEMBLY". United States. doi:10.1088/2041-8205/735/2/L43.
@article{osti_21562547,
title = {KINEMATICS AND FINE STRUCTURE OF AN UNWINDING POLAR JET OBSERVED BY THE SOLAR DYNAMIC OBSERVATORY/ATMOSPHERIC IMAGING ASSEMBLY},
author = {Shen Yuandeng and Liu Yu and Su Jiangtao and Ibrahim, Ahmed, E-mail: ydshen@ynao.ac.cn},
abstractNote = {We present an observational study of the kinematics and fine structure of an unwinding polar jet, with high temporal and spatial observations taken by the Atmospheric Imaging Assembly on board the Solar Dynamic Observatory and the Solar Magnetic Activity Research Telescope. During the rising period, the shape of the jet resembled a cylinder with helical structures on the surface, while the mass of the jet was mainly distributed on the cylinder's shell. In the radial direction, the jet expanded successively at its western side and underwent three distinct phases: the gradually expanding phase, the fast expanding phase, and the steady phase. Each phase lasted for about 12 minutes. The angular speed of the unwinding motion of the jet and the twist transferred into the outer corona during the eruption are estimated to be 11.1 x 10{sup -3} rad s{sup -1} (period = 564 s) and 1.17-2.55 turns (or 2.34-5.1{pi}), respectively. On the other hand, by calculating the azimuthal component of the magnetic field in the jet and comparing the free energy stored in the non-potential magnetic field with the jet's total energy, we find that the non-potential magnetic field in the jet is enough to supply the energy for the ejection. These new observational results strongly support the scenario that the jets are driven by the magnetic twist, which is stored in the twisted closed field of a small bipole, and released through magnetic reconnection between the bipole and its ambient open field.},
doi = {10.1088/2041-8205/735/2/L43},
journal = {Astrophysical Journal Letters},
issn = {2041-8205},
number = 2,
volume = 735,
place = {United States},
year = {2011},
month = {7}
}