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Title: HOMOLOGOUS HELICAL JETS: OBSERVATIONS BY IRIS, SDO, AND HINODE AND MAGNETIC MODELING WITH DATA-DRIVEN SIMULATIONS

Abstract

We report on observations of recurrent jets by instruments on board the Interface Region Imaging Spectrograph, Solar Dynamics Observatory (SDO), and Hinode spacecraft. Over a 4 hr period on 2013 July 21, recurrent coronal jets were observed to emanate from NOAA Active Region 11793. Far-ultraviolet spectra probing plasma at transition region temperatures show evidence of oppositely directed flows with components reaching Doppler velocities of ±100 km s{sup −1}. Raster Doppler maps using a Si iv transition region line show all four jets to have helical motion of the same sense. Simultaneous observations of the region by SDO and Hinode show that the jets emanate from a source region comprising a pore embedded in the interior of a supergranule. The parasitic pore has opposite polarity flux compared to the surrounding network field. This leads to a spine-fan magnetic topology in the coronal field that is amenable to jet formation. Time-dependent data-driven simulations are used to investigate the underlying drivers for the jets. These numerical experiments show that the emergence of current-carrying magnetic field in the vicinity of the pore supplies the magnetic twist needed for recurrent helical jet formation.

Authors:
; ; ; ; ; ; ; ; ;  [1]; ; ; ; ; ;  [2];  [3]; ;  [4];  [5] more »; « less
  1. Lockheed Martin Solar and Astrophysics Laboratory, 3251 Hanover Street Bldg. 252, Palo Alto, CA 94304 (United States)
  2. Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States)
  3. University of Applied Sciences and Arts Northwestern Switzerland, Bahnhofstr. 6, 5210 Windisch (Switzerland)
  4. Department of Physics, Montana State University, Bozeman, P.O. Box 173840, Bozeman, MT 59717 (United States)
  5. Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029, Blindern, NO-0315 Oslo (Norway)
Publication Date:
OSTI Identifier:
22522064
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 801; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CHROMOSPHERE; COMPARATIVE EVALUATIONS; EMISSION SPECTRA; FAR ULTRAVIOLET RADIATION; JETS; MAGNETIC FIELDS; PHOTOSPHERE; PLASMA; SPACE VEHICLES; SUN; TIME DEPENDENCE; TOPOLOGY; VELOCITY

Citation Formats

Cheung, Mark C. M., Pontieu, B. De, Tarbell, T. D., Fu, Y., Martínez-Sykora, J., Boerner, P., Wülser, J. P., Lemen, J., Title, A. M., Hurlburt, N., Tian, H., Testa, P., Reeves, K. K., Golub, L., McKillop, S., Saar, S., Kleint, L., Kankelborg, C., Jaeggli, S., Carlsson, M., E-mail: cheung@lmsal.com, and and others. HOMOLOGOUS HELICAL JETS: OBSERVATIONS BY IRIS, SDO, AND HINODE AND MAGNETIC MODELING WITH DATA-DRIVEN SIMULATIONS. United States: N. p., 2015. Web. doi:10.1088/0004-637X/801/2/83.
Cheung, Mark C. M., Pontieu, B. De, Tarbell, T. D., Fu, Y., Martínez-Sykora, J., Boerner, P., Wülser, J. P., Lemen, J., Title, A. M., Hurlburt, N., Tian, H., Testa, P., Reeves, K. K., Golub, L., McKillop, S., Saar, S., Kleint, L., Kankelborg, C., Jaeggli, S., Carlsson, M., E-mail: cheung@lmsal.com, & and others. HOMOLOGOUS HELICAL JETS: OBSERVATIONS BY IRIS, SDO, AND HINODE AND MAGNETIC MODELING WITH DATA-DRIVEN SIMULATIONS. United States. doi:10.1088/0004-637X/801/2/83.
Cheung, Mark C. M., Pontieu, B. De, Tarbell, T. D., Fu, Y., Martínez-Sykora, J., Boerner, P., Wülser, J. P., Lemen, J., Title, A. M., Hurlburt, N., Tian, H., Testa, P., Reeves, K. K., Golub, L., McKillop, S., Saar, S., Kleint, L., Kankelborg, C., Jaeggli, S., Carlsson, M., E-mail: cheung@lmsal.com, and and others. 2015. "HOMOLOGOUS HELICAL JETS: OBSERVATIONS BY IRIS, SDO, AND HINODE AND MAGNETIC MODELING WITH DATA-DRIVEN SIMULATIONS". United States. doi:10.1088/0004-637X/801/2/83.
@article{osti_22522064,
title = {HOMOLOGOUS HELICAL JETS: OBSERVATIONS BY IRIS, SDO, AND HINODE AND MAGNETIC MODELING WITH DATA-DRIVEN SIMULATIONS},
author = {Cheung, Mark C. M. and Pontieu, B. De and Tarbell, T. D. and Fu, Y. and Martínez-Sykora, J. and Boerner, P. and Wülser, J. P. and Lemen, J. and Title, A. M. and Hurlburt, N. and Tian, H. and Testa, P. and Reeves, K. K. and Golub, L. and McKillop, S. and Saar, S. and Kleint, L. and Kankelborg, C. and Jaeggli, S. and Carlsson, M., E-mail: cheung@lmsal.com and and others},
abstractNote = {We report on observations of recurrent jets by instruments on board the Interface Region Imaging Spectrograph, Solar Dynamics Observatory (SDO), and Hinode spacecraft. Over a 4 hr period on 2013 July 21, recurrent coronal jets were observed to emanate from NOAA Active Region 11793. Far-ultraviolet spectra probing plasma at transition region temperatures show evidence of oppositely directed flows with components reaching Doppler velocities of ±100 km s{sup −1}. Raster Doppler maps using a Si iv transition region line show all four jets to have helical motion of the same sense. Simultaneous observations of the region by SDO and Hinode show that the jets emanate from a source region comprising a pore embedded in the interior of a supergranule. The parasitic pore has opposite polarity flux compared to the surrounding network field. This leads to a spine-fan magnetic topology in the coronal field that is amenable to jet formation. Time-dependent data-driven simulations are used to investigate the underlying drivers for the jets. These numerical experiments show that the emergence of current-carrying magnetic field in the vicinity of the pore supplies the magnetic twist needed for recurrent helical jet formation.},
doi = {10.1088/0004-637X/801/2/83},
journal = {Astrophysical Journal},
number = 2,
volume = 801,
place = {United States},
year = 2015,
month = 3
}
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