Topology and dynamics
of solar prominences(Option B)	
2010.03.11
Takenori J. Okamoto & T. E. Berger(NAOJ)	

(LMSAL)	

! Recent Hinode observations have shown “dynamic” activities
in fine structures of prominences.
! Active motions of fine structures provide various information	
lateral motion(Alfvenic wave)	

(Okamoto et al. 2007)	

horizontal flowin vertical structure	

vertical motion (largebubble, small plume)	

(Chae et al. 2008)	

(see Berger et al. 2008, 2010)	

strength of mag. fields	

structure of mag. fields	
density and temperature of plasma	Impact of prominence	! Visualization of coronal field and information
about density of plasma are useful forinvestigations of! magnetic configuration in the corona! energy transfer by MHD waves! triggering mechanism of flares and CMEs

! Necessary to clarify! fine structures! formation and evolution process! dynamical phenomena (bubble etc.)

Fine structures	
! width < 0.3” by SST observations (Lin et al. 2005)! mag. field strength, plasma density of each thread ?
! important to understand the property of mag. field from thephotosphere to the corona! What is located in between threads ?	
Not so strong request toachieve 0.1” resolution（0.2” is enough ?）High-res. obs. without
physical quantity cannot
provide useful information 	Magnetic configuration is helical ?	
! Yes! flux rope in the corona (e.g., Gibson &Fan 2006)! speculation from photospheric!

mag. fields （Lites 2005)
magnetic dips support cool mass
Lites (2005)! No! magnetic shear and minority!

polarity patches
flows along threads maintain mass
(Zirker et al. 1998, Karpen et al. 2001)	

Martin (1998)

Magnetic configuration	
vector mag. fieldvector velocity
simultaneously! 200”x 100”
! 0.3” (slitscan 0.15”)! limb observation is better(easier to get information about height)
impossible from ground withconsiderations of dynamic prominence& AO does not work at the limb
 space obs. is required	

3D configuration along
magnetic fieldFormation of mag. field	
About helical field	
! flux rope model
originally-twisted flux emerges
from below the photosphere	

Rust & Kumar (1994)! sheared-arcade modelby photospheric shear andconverging motions, andreconnection in the corona

van Ballegooijen & Martens (1989)

Formation of mag. field	
! good example of helical flux emergence under prominence! question : this flux emergence contributed formation ofprominence ?	

Okamoto et al. (2008)

(deg)
+90
0-90

To know the behavior of the emerging flux in the chromosphere and corona,simultaneous observation of chromospheric fields is important in addition tophotospheric vector fields.	

Plumes and bubbles	
Hinode/SOT discovered dynamic phenomena inprominence.	
bubble	plume	

Berger et al. (2008)

Plumes and bubbles	! What are these ?
! flux emergence ?
! hot component ?	
The true identity
remains unknown.	
Berger et al. (2010)

spectrometric observation is required for the dynamics
 information about time evolution of density and velocity	Prominence observations	! Most of the prominence studies (as chromosphericmaterial) with Hinode are performed only with“filtergraph”.
! For accurate and quantitative studies, we need toobserve density, LOS velocity, and chromosphericmag. field of fine structures with! spectrometer! spectro-polarimeter! in addition to photospheric vector fields (Hinode/SP)! High-cadence observations are required in any
cases of prominence studies.

Measurement of mag. field in prominence	! long-integration time is required formeasurement (accuracy : 10-3 ~ -4)! due to seeing! 20~50-min average for spicule （Centenoet al. 2009）! 100-s integration for prominence（Merenda et al. 2006)

Casini et al. (2003)	

! 2~3” res. to achieve the accuray! acceptable for “dynamic”
chromosphere ?
! assumed that material moves along
stationary mag. fields	

Large advantage of space observation

Merenda et al. (2006)	

HAO ProMag	
! Prominence Magnetometer! Sac Peak, 40-cm aperture! res. 2~3”, FOV >100”! 2 wavelengths, simultaneously （5876 or 6563 +10830）

Important issue :Measurement of prominence fields “actually” provide
useful information without difficulty to analyze ?
 guideline for Option-B (as is also IRIS)

Summary	
! Observation of chromospheric mag. fields fromspace has a significant advantage to investigate
prominences itself and the surrounding
environment.
! Note that prominence is a part of overallmagnetic structures. We have to observe not
only cool material but also photospheric fields
and its coronal cavity, simultaneously.
! Chromosphere including prominence is so
dynamic that high telemetry is essential for thestudies. (Option B)request to Option-B	! spatial resolution ~< 0.2” (100 cm @ 10,000 A)! FOV 200”x 200” (~SOT/FG)! cadence : 8 s (0.2” displacement with 20 km/s)! long-duration observation is also important! spectrometry： Mg ? Na D ? He I ? H I ?
! spectro-polarimetry： < 0.05% (see ProMag）