2003-2004 Annual report to NASA on progress of NRA 00-OSS-01 SEC
Sun-Earth Connection Guest Investigator Program Research.
(Year 3 of a 3-year grant)
Wave propagation in the solar atmosphere.
17 March 2004
PI: Dr. Thomas J. Bogdan
National Center for Atmospheric Research
High Altitude Observatory
3450 Mitchell Lane
Boulder, CO 80301
Prof. Mats Carlsson, collaborator
Institute of Theoretical Astrophysics
University of Oslo
PO Box 1029 Blindern
N-0315 Oslo, Norway
tel. 303-497-1457
fax 303-497-1589
e-mail: tom@hao.ucar.edu
tel. +47-2285 6501
fax +47-2285 6505
e-mail: mats.carlsson@astro.uio.no
http://www.astro.uio.no/~matsc/
Dr. Philip Judge, co-PI
National Center for Atmospheric Research
High Altitude Observatory
3450 Mitchell Lane
Boulder CO 80301
e-mail: judge@hao.ucar.edu
tel. 303-497-1502
fax 303-497-1589
Dr. Elizabeth J. Zita, co-PI
The Evergreen State College
Lab II, Physics & Astronomy
Olympia, WA 98505, USA
e-mail: zita@evergreen.edu
tel. (360) 867-6853, fax (360) 867-5430
(on medical leave?)
http://academic.evergreen.edu/z/zita/home.htm
A. CONTINUING WORK: OLD
1. Numerical analyses of MHD simulations.
Following the methods of Rosenthal et al. (2002), and building on work by Evergreen
undergraduates (Johnson et al., 2002), Bogdan and Zita continue to analyze MHD mode mixing
and interactions due to localized wave sources in magnetic flux concentrations. We investigated
several possible formulations of energy flux, and found that some appear to describe circulation
while others better describe actual propagation. Our fourth team of Evergreen undergraduates is
currently learning solar physics and data analysis techniques in order to contribute to this research
in summer 2004.
2. Analysis and interpretation of chromospheric UV data.
While on medical leave, Judge continued independent analysis of chromospheric UV data,
following the methods of Judge et al. (2001). Spanning wavelengths from 170 to 91 nm and
heights from 0.4 to 1.8 Mm, the UV signals are brighter where plasma temperatures are higher or
magnetic fields are stronger (Lites, 1993?). Judge did ___ and found ___
(Here are results from last year.)
(1)
Power in the 2-5 mHz band appears increases with wavelength (or decrease with
height) in the chromosphere (Fig.1, attached document).
(2)
In the 0-2 frequency range, there is consistently more power in the network
(magnetic) regions than in internetwork regions.
(3)
In the 5-10 frequency range, there tends to be more power in the internetwork
regions.
3. Comparison of observations with simulations.
The UV observations in A.2 complement our simulation analyses in A.1. We compared
strengths of various waves and their energy fluxes as they propagate up from the photosphere in
network regions with localized radial drivers. For example, the observed decrease of p-mode
power with altitude is consistent with simulations showing decreasing amplitudes of acoustic
waves in the chromosphere, even when they steepen into shocks. Higher amplitudes of magnetic
waves in the simulations indicate that acoustic oscillations mode-convert to MHD waves,
especially near =1 regions. Simulations show clear evidence of magnetosonic waves propagating
across penumbral wings of network regions, consistent with observations of running penumbral
waves. Simulations also show clear evidence of excitation of Alfvénic, magnetosonic, and hybrid
MHD waves, The extent to which these waves carry significant energy to higher altitudes depends
on resolving the question of circulating flux versus propagating flux, noted in A.1.
Synthesizing simulation analyses and data analyses contributes to our development of a
clearer understanding of mode interactions and the possible role of magnetic waves in heating the
chromosphere.
B. NEW WORK
During 2002-03, Zita synthesized results from Evergreen students’ analyses of simulation data in
summer 2001 (Johnson et al. 2002) and observational data in summer 2002 (Heller et al. 2003),
which are documented in our previous annual reports to NASA. Zita presented the synthesis at the
AGU meeting in Dec.2003.
In academic year 2003-04, a new team of Evergreen undergraduates is learning solar physics by
reading the papers above and supporting articles. Zita provided these learning opportunities,
including workshops and tutorials, while on unpaid leave in fall 2003.
Our research team met for a week of planning and work in Oslo in Sept.2003. Bogdan facilitated a
discussion of our new ApJ paper, and led our planning activities. We agreed to a list of future
analyses and decided who will be responsible for each task. These are listed in D. Future Plans
below.
Carlsson and colleagues at ITA provided access to their complete set of simulation data and IDL
analysis programs, to share with Evergreen undergraduates. Zita learned new techniques for
analyzing these data, and began writing new code to carry out our plans for Evergreen’s
contribution to our continued work, focusing on energy flux analyses and the generation of (k)
diagrams from simulations.
We have completed the establishment of a basic solar physics research infrastructure at Evergreen.
With the help of technicians at the Computer Applications Laboratory on campus, we have
expressly dedicated a public Linux workstation to our research, in a homeroom set aside for
advanced physics students. (Unfortunately, Windows is the primary operating system on campus.)
All the simulation data and analysis programs from Bogdan and Carlsson have been downloaded to
this workstation, together with Zita’s new codes. New research students have learned Linux, IDL,
LaTex, and are already modifying existing programs and practicing with data analysis, in
preparation for our coming research summer. The homeroom also houses a growing library of solar
physics texts and technical manuals, including tutorials written by Evergreen alums for
undergraduates following their footsteps
Bogdan finished his two-year tour of duty at NSF in October 2003, and has returned to
HAO/NCAR. He continues to analyze simulation data and to advise the Evergreen team on our
work. (More about your new work, Tom…).
________________________________________________________
Tom: Should we include discussions of Mats’ work?
C. DISSEMINATION
New publications resulting from this past year’s work include Bogdan et al. (Ap.J., 2003)
 Articles by Mats? (I have his list)
 Articles by Phil (should we include?)
The simulation analyses of the first team of Evergreen undergraduates in summer 2001 are
documented in our 2001 NASA report and detailed in their paper (Johnson et al., 2002). The
observational data analyses of the summer 2002 team is documented in last year’s NASA report
and detailed in Heller et al., 2003. The synthesis of these works is documented on Zita’s research
page at Evergreen, and has been incorporated into colleagues’ publications above. Articles such as
these serve as important resources in training successive teams of Evergreen undergraduate
research students.
Zita continues to give presentations about astronomy and solar physics research, at a reduced rate
while on leave in Fall 2003. Outreach in the first half of the 2003-2004 academic year included
four talks at Olympia high schools, a workshop for middle school girls at Expanding Your
Horizons, and the AGU poster in SF.
Bogdan has presented our joint solar physics research at (lots and lots of meetings)
….
Mats Carlsson presented research results at …
Judge is still on medical leave, and writing articles from home, based on analysis of chromospheric
UV data.
D. FUTURE PLANS
In our team planning meeting in Oslo in Sept. 2003, we agreed to the following six new tasks.
Tom, insert your list, or I will reconstruct from my notes…
The Evergreen team’s ability to complete our share of the tasks (in energy flux analysis and (k)
diagrams) depends on future funding, as our current grant expires in May.2004. The steps below
may help provide some of the required resources for our future work:
 No-cost extension of current NASA grant through summer 2004
 New proposals to funding agencies, including (paste new NASA proposal number)
If these resources become available, Zita and two Evergreen undergraduates plan to work at HAO
again for part of summer 2004. As the Evergreen team has learned the skills and established the
local infrastructure to more independently fulfill our commitments to our joint research activities,
we may spend less time in Boulder and more time working in Olympia. As discussed in B. above,
students are currently working on simulation data analysis at Evergreen, at a slower pace during the
academic year, when we all have full-time commitments to classes.
Bogdan has been invited to visit Evergreen for another public presentation in spring 2004, and to
meet with our student candidates for summer research.
We will continue documenting our work with posters, presentations, and internal papers by the
Evergreen team and refereed journal articles by Bogdan and co-PIs.
If our research is funded for the next three years, it is time for Zita and the Evergreen team to turn
our internal papers into refereed journal articles.
References:
Bogdan, T.J., Carlsson, M, Hansteen, V., McMurray, A, Rosenthal, C.S., *Johnson, M., *PettyPowell, S., Zita, E.J., Stein, R.F., McIntosh, S.W., Nordlund, Å., 2003, “Waves in the magnetized
solar atmosphere II: waves from localized sources in magnetic flux concentrations”, ApJ 597
Bogdan et al., AGU poster
T.J. Bogdan, C.S. Rosenthal, M. Carlsson, V. Hansteen, A. McMurry, E.J. Zita, M. Johnson, S.
Petty-Powell, S.W. McIntosh, A. Nordlund, R.F. Stein, and S.B.F. Dorch, Astronomische
Nachrichten, 323(3-4), 196-202, 2002.
N. Heller and E.J. Zita, Chromospheric UV emissions: frequency spectra in network and
internetwork regions, 2003, linked at http://academic.evergreen.edu/z/zita/research.htm
N. Heller and E.J. Zita, Chromospheric UV oscillations depend on altitude and local magnetic
field, poster presented at SHINE workshop in Banff, Aug 2002, linked at
http://academic.evergreen.edu/z/zita/research.htm
M. Johnson and S. Petty-Powell, Energy transport by waves above the photosphere: numerical
simulations, 2002
http://academic.evergreen.edu/z/zita/students/matt/mattmhd.pdf
M. Johnson and S. Petty-Powell, Magnetic energy transformations in the solar atmosphere:
numerical results, 2001,
http://online.itp.ucsb.edu/online/solar_c02/p_johnson/
P.G Judge, T.D Tarbell and K. Wilhelm, 2001, A Study of Chromospheric Oscillations using the
SOHO and TRACE spacecraft, Astrophysical Journal 554, 424
C.S. Rosenthal and T.J. Bogdan, 2002 Astrophysical Journal 564, pp. 08-52, Waves in the
Magnetized Solar Atmosphere. I. Basic Processes and Internetwork Oscillations
E.J. Zita, Magnetic Waves in Sheared Field Regions, poster presented at SHINE workshop in
Banff, Aug 2002, linked at http://academic.evergreen.edu/z/zita/research.htm
E.J. Zita, MHD waves in a sheared magnetic field, 2003, paper linked at
http://academic.evergreen.edu/z/zita/research.htm
Zita et al, AGU poster
TIMELINE – NOT FOR PUBLICATION
spring 2000?: Zita visited HAO, Tom wrote our first proposal
Summer 2001: HAO with Matt and Sara yielded Johnson et al. 2001
Summer 2002: HAO with Noah and AB yielded Heller et al. 2002
Summer 2003: no HAO visit. Worked with Jason and Katherine in academic year 2002-03. Zita
synthesized MS simulation analyses from summer 2001 with NH data analyses from summer 2002
Fall 2003: Zita on unpaid leave: planning activities in Oslo (early Sept.) and solar physics journal
club with contract students: Andrew White, Joey, Night, Chris
Summer 2004: return to HAO with Chris Dove and Night Song? Jason Wall?