Formation and Impact of Type II Spicules

ROSES ID: NNH10ZDA001N      Selection Year: 2011      

Program Element: Sun Climate

Principal Investigator: Bart De Pontieu

Project Member(s):
Carlsson, Mats Collaborator University of Oslo
Hansteen, Viggo Haraldson Collaborator University of Oslo
Rouppe van der Voort, Luc Collaborator Universitetet i Oslo
McIntosh, Scott William Co-I National Center for Atmospheric Research
Martinez Sykora, Juan Collaborator Lockheed Martin Solar & Astrophysics lab

Summary:

We propose to study the formation and impact on the solar atmosphere of so-called type II spicules using a broad range of observations that cover all temperatures between photosphere and corona, in combination with state-of-the-art radiative 3D MHD numerical simulations of a domain encompassing the convection zone through the photosphere, chromosphere into the corona. Type II spicules are the most ubiquitous jets in the solar atmosphere with the largest potential for playing a significant role in the mass and energy balance of the corona and solar wind. We will build on our recent discovery of this novel, more violent type of spicules that appear to be associated with rapid upflows with velocities of order 50-100 km/s in the lower solar atmosphere including the transition region and corona. These upflows may be the "missing link" at the heart of the solar plasma energization quandary, and are specifically called out in the description of Focused Science Topic (c) of the TR&T Announcement of Opportunity (AO). We will investigate what role the magnetic field and photospheric dynamics play in their formation, and whether these chromospheric jets play a major role in providing the corona and solar wind with hot plasma.

We will use an arsenal of coordinated observations, covering the temperatures between photosphere and corona - including data from Hinode/SOT-EIS-XRT, SDO, Swedish Solar Telescope, and the Interface Region Imaging Spectrograph (IRIS, to be launched in December 2012). We will exploit our discovery of the disk counterpart of type II spicules (so-called rapid-blueshifted events, or RBEs) to avoid the enormous line-of-sight superposition that has plagued spicule studies at the limb for many decades. We will use already developed automated detection software to determine and develop a database of detailed properties of thousands of these jets for a variety of solar targets. We will combine these measurements with magnetic field measurements in both the photosphere and chromosphere to investigate the role of reconnection and flux emergence in the formation mechanism(s) of these jets. To gauge the impact of chromospheric jets on the corona and solar wind, we will study the association of these jets with brightenings in TR/coronal images of the footpoints of coronal loops, and with high velocity blue-wing asymmetries of TR/coronal spectral line profiles at the loop footpoints. We will exploit the presence of a weak, but significant, coronal response to chromospheric jets to provide an accurate estimate of the mass and energy flux carried into the corona by heating events associated with spicules. The observations will be rigorously compared with synthetic observables of jets from radiative 3D MHD numerical simulations (from our no-cost collaborators in Oslo) that include seed magnetic fields derived from our photospheric observations. The combined results of these investigations will help reveal how these jets form and whether they play a significant role in the heating of plasma to coronal temperatures.

The proposed research is highly relevant to the scientific goals of the Focused Science Topic (c) on Jets in the Solar Atmosphere and will be a strong contribution to the Focus Team's efforts. Our research will directly involve three of the four different types of investigations listed in the AO. We will "characterize the properties of chromospheric jets", "study the statistics of the jets and their role in providing mass and energy to the corona and solar wind", and "develop physical models of jet acceleration". We will directly advance "our understanding of the origins, structure and dynamics of chromospheric jets", and the combination of observations and modeling will lead to "models for the UV-X-ray emission from jets and their contribution to the mass and energy flux of closed and open fields in the corona and solar wind". All of these are direct measures of success outlined in the AO.

Publications:

Performance Year	Reference	Investigation Type	Actions
1	Judge, Philip G.; de Pontieu, Bart; McIntosh, Scott ...	not set
1	Sekse, D. H.; Rouppe van der Voort, L.; De Pontieu,...	not set
1	De Pontieu, B.; Carlsson, M.; Rouppe van der Voort,Â...	not set
1	Pereira, Tiago M. D.; De Pontieu, Bart; Carlsson, Ma...	not set
1	Pereira, Tiago M. D.; De Pontieu, Bart; Carlsson, Ma...	not set
1	Sekse, D. H.; Rouppe van der Voort, L.; De Pontieu,...	not set
1	Sekse, D. H.; Rouppe van der Voort, L.; De Pontieu,...	not set
1	Martínez-Sykora, Juan; De Pontieu, Bart; Leenaarts, J...	not set
1	Pereira, T. M. D.; De Pontieu, B.; Carlsson, M.; Ha...	not set
1	Rouppe van der Voort, L.; De Pontieu, B.; Pereira, ...	not set
1	Skogsrud, H.; Rouppe van der Voort, L.; De Pontieu,Â...	not set

Presentations:

Performance Year	Reference	Actions
1	Chamberlin, Phillip C.; Allred, J.; Airapetian, V.; G...
1	Chamberlin, P. C.; Allred, J. C.; Airapetian, V.; Go...
1	Pereira, T. M.; De Pontieu, B.; Carlsson, M.; (2011),...

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