Distribution and dynamics of the solar magnetic flux in the photosphere and heliosphere

ROSES ID: NNH06ZDA001N      Selection Year: 2007      

Program Element: Independent Investigation

Principal Investigator: Valentyna Abramenko

Affiliation(s): Big Bear Solar Observatory

Project Member(s):
Yurchyshyn, Vasyl Co-I New Jersey Institute of Technology
Zurbuchen, Thomas H Co-I University of Michigan
Fisk, Len Co-I University of Michigan

Summary:

This proposal is being written in response to a request by the TRT focus team

on "Solar and Heliospheric Magnetic Field" led by T.H. Zurbuchen, University of

Michigan. The team, and especially its lead, have encouraged to propose for a

third year of funding to allow a successful completion of the focus team work.

The need for this proposal arises from two reasons. First, our initial proposal

extended only over two years. We are well on the way to achieving the

statements of work (SOW) for this initially proposed research. Second, in

response to team-objectives, we have adjusted our SOW to be of maximum help to

the focus team and our work is now well connected to other parts of the

team-work.



During the first year of our collaboration we have analyzed dynamics of

emergence of new dipoles inside coronal holes and in adjacent quiet-Sun areas.

We have shown for the first time that the dipole emergence rate of the

magnetic flux inside coronal holes is suppressed as compared to the quiet sun

areas. This finding agrees with the idea that coronal holes are formed at

location where the dipole emergence rate is low and therefore open magnetic

flux can be accumulated at these places (theory of the coronal holes formation

and solar wind acceleration, Fisk 2005). This theory suggests that

reconnection between open magnetic flux and closed magnetic loops is an

essential diffusion mechanism for open filed lines.



We are currently improving and modifying our existing algorithms and numerical

codes to calculate power spectra of magnetic field fluctuations (both spatial

and temporal) as well as high statistical structure functions, which would

allow us to derive flatness functions and filling factor and estimate

intermittency of the magnetic field both in the photosphere and in the solar

wind. This analysis will then be compared to the results of other team members

(both observational and theoretical). Our funding is likely to run out before

the completion of this collaboration, which is an important part of the work

by the focus team.



During the third year, we will study magnetic flux distribution in the

photosphere both inside and outside of coronal holes. We intend to apply our

techniques to photospheric and solar wind measurements. Conclusions and

parameters obtained from the study will be used as input date

and/or constrain the models of coronal hole formation and solar wind

acceleration developed by our focus team.

Publications:

Performance Year	Reference	Investigation Type	Actions
1	Abramenko, Valentyna; Yurchyshyn, Vasyl; Wang, Haimin; ...	not set

Presentations:

Performance Year	Reference	Actions
1	Abramenko, Valentyna; Pevtsov, A.; (2007), Magnetic Diss...
1	Abramenko, V.; Yurchyshyn, V.; Wang, H.; (2008), Interm...
1	Abramenko, Valentyna; (2009), How the Magnetic Flux Insid...
1	Abramenko, Valentyna; (2011), Turbulent Diffusion on Very S...

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