AN INTRIGUING CHROMOSPHERIC JET OBSERVED BY HINODE: FINE STRUCTURE KINEMATICS AND EVIDENCE OF UNWINDING TWISTS

Journal Article · Thu Dec 10 00:00:00 EST 2009 · Astrophysical Journal (Online)

DOI:https://doi.org/10.1088/0004-637X/707/1/L37· OSTI ID:21389324

Wei, Liu; Berger, Thomas E; Title, Alan M; Tarbell, Theodore D ^[1]

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1. Lockheed Martin Solar and Astrophysics Laboratory, Department ADBS, Building 252, 3251 Hanover Street, Palo Alto, CA 94304 (United States)

We report a chromospheric jet lasting for more than 1 hr observed by the Hinode Solar Optical Telescope in unprecedented detail. The ejection occurred in three episodes separated by 12-14 minutes, with the amount and velocity of material decreasing with time. The upward velocities range from 438 to 33 km s{sup -1}, while the downward velocities of the material falling back have smaller values (mean: -56km s{sup -1}) and a narrower distribution (standard deviation: 14km s{sup -1}). The average acceleration inferred from parabolic spacetime tracks is 141 m s{sup -2}, a fraction of the solar gravitational acceleration. The jet consists of fine threads (0.''5-2'' 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{sup -1}at the leading front of the jet. The transverse oscillation velocities range from 151 to 26 km s{sup -1}, 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.

• OSTI ID: 21389324
• Journal Information: Astrophysical Journal (Online), Vol. 707, Issue 1; Other Information: DOI: 10.1088/0004-637X/707/1/L37; ISSN 1538-4357
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
ACCELERATION
CHROMOSPHERE
FINE STRUCTURE
HELICITY
OSCILLATIONS
PARTICLE TRACKS
SOLAR CORONA
SOLAR FLARES
SPACE-TIME
SUN
TELESCOPES
ATMOSPHERES
MAIN SEQUENCE STARS
PARTICLE PROPERTIES
SOLAR ACTIVITY
SOLAR ATMOSPHERE
STARS
STELLAR ACTIVITY
STELLAR ATMOSPHERES
STELLAR CORONAE
STELLAR FLARES