An Intriguing Chromospheric Jet Observed by Hinode: I. Fine Structure Kinematics and Evidence of Unwinding Twists

Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

6 pages, 4 figures, accepted by The Astrophysical Journal Letters (2009 Oct 27); online only material (movies) available at:

Scientific paper

We report a chromospheric jet lasting for more than 1 hr observed by Hinode Solar Optical Telescope in unprecedented detail. The ejection occurred in three episodes separated by 12-14 min, with the amount and velocity of material decreasing with time. The upward velocities range from 438 to 33 km/s, while the downward velocities of the material falling back have smaller values (mean: -56 km/s) and a narrower distribution (standard deviation: 14 km/s). The average acceleration inferred from parabolic space-time tracks is 141 m/s^2, a fraction of the solar gravitational acceleration. The jet consists of fine threads (0.5-2.0 arcsec wide), which exhibit coherent, oscillatory transverse motions perpendicular to the jet axis and about a common equilibrium position. These motions propagate upward along the jet, with the maximum phase speed of 744 +/- 11 km/s at the leading front of the jet. The transverse oscillation velocities range from 151 to 26 km/s, amplitudes from 6.0 to 1.9 Mm, and periods from 250 to 536 s. The oscillations slow down with time and cease when the material starts to fall back. The falling material travels along almost straight lines in the original direction of ascent, showing no transverse motions. These observations are consistent with the scenario that the jet involves untwisting helical threads, which rotate about the axis of a single large cylinder and shed magnetic helicity into the upper atmosphere.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

An Intriguing Chromospheric Jet Observed by Hinode: I. Fine Structure Kinematics and Evidence of Unwinding Twists does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with An Intriguing Chromospheric Jet Observed by Hinode: I. Fine Structure Kinematics and Evidence of Unwinding Twists, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and An Intriguing Chromospheric Jet Observed by Hinode: I. Fine Structure Kinematics and Evidence of Unwinding Twists will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-483638

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.