1. Observations of emerging and submerging regions with ASP and Solar-B
Masahito Kubo (University of Tokyo)

2. Introduction Emerging flux region
Observations with high accurate photospheric vector magnetic field
are important to understand the flux emergence processes
We observed an evolving active region that have significant emerging flux with ASP
We obtain vector magnetic properties of initial stages of emerging flux
Submerging region
A large-scale cancellation region was formed in our observed active region
This is first observation of cancellation region with vector magnetic field

3. Emerging and Submerging region in NOAA9231
move clockwise around leading sunspot
move to cancellation region
SoHO/MDI
bright loops appear and
connect emerging bipole
bright structure appear above
the cancellation region
Yohko/SXT
pre-existing loop-like structures
New connection appear

4. Observation of rapidly emerging bipole
a few hours old after their first appearance
their evolution during three hours was observed with ASP
Emerging region
19-NOV-00 17:41:50UT

5. Evolution of emerging flux in early phase
Magnetic flux
Pre-existing magnetic flux hide the negative pair
horizontal
vertical(outward)
vertical(inward)
Filling factor
• filling factor represent percentage of each pixel occupied by magnetic atmosphere
black represent large quantities of magnetic atmosphere are contained in a pixel
High filling factor (>80%) area appears between active emerging bipole.

6. Vector magnetic properties of high filling factor area
Inclination（θ）[deg]
vertical(inward)
In high filling factor area, the
direction of magnetic field is
horizontal to solar surface 5″
horizontal
vertical(outward)
Magnetic field strength(|B|) [Gauss]
Magnetic field strength in high filling
factor area is weaker (500 Gauss) than
surrounding horizontally oriented
magnetic field (800Gauss).
500[Gauss]
1600[Gauss]
800[Gauss]

7. Doppler velocity(vLOS) [km/s] line of sight
velocity of magnetic atmosphere
upward
upward velocity (~0.5 km/s)
downward

8. Summary of emerging flux region
High filling factor area appears between active emerging bipole with flux emergence
horizontal to the solar surface
Weak field strength (500Gauss)
upward velocity (0.5 km/s)
consistent with other ASP
observations of newly
emerging flux
(Lites et al. 1998)
• Another two active emerging bipoles were observed (One was after about
3 hours from their first appearance and another was after 12 hours)
High filling factor areas were also located between both active emerging bioples
Properties of magnetic fields in the high filling factor areas are almost same

9. Emerging and Submerging region in NOAA9231
move clockwise around leading sunspot
move to cancellation region
SoHO/MDI
bright loops appear and
connect emerging bipole
bright structure appear above
the cancellation region
Yohko/SXT
pre-existing loop-like structures
New connection appear

10. Magnetic field between colliding poles
magnetic flux map (ASP)
(arrow:tangential component, green line: neutral line)
vertical(inward)
horizontal
vertical(outward)
Horizontally oriented magnetic fields
increase during three days and they
connect colliding poles.

11. Horizontal magnetic field with downward velocity
Doppler velocity(vLOS) [km/s]
Perpendicular motion
extract horizontally oriented magnetic field
(45°< θ <135°)
upward
20-NOV-00 14:52:02(S24W24) + + － － + +
downward
Horizontally oriented magnetic fields have downward velocity
between colliding poles  submerging magnetic field

12. Field strength and filling factor in cancellation region
20-NOV-00 14:52:02
Magnetic field strength[Gauss]
horizontally oriented magnetic field
between colliding poles
 400 – 1500 Gauss　>　typical horizontal
magnetic field + － +
Filling factor
high filling factor (>80%) area exist
high filling factor area is almost coincided
with downward velocity area + A1 － +

13. Solar-B observation of cancellation region
Reconnection model
Corona (XRT, EIS)
bright structures between colliding poles + － + －
Photosphere (SOT)
horizontally oriented magnetic field
with downward velocity between
colliding poles
before reconnection
corona
Solar-B will be able to observe
submerging motion of identical
magnetic loop from corona
to photosphere
chromosphere
photosphere + － + －
after reconnection

14. Summary We obtain the vector magnetic properties of emerging and
submerging (cancellation) region as follow;
Emerging region
Submerging region
Doppler velocity upward (~0.5 km/s) downward (~0.5 km/s)
Inclination horizontal　　　　 horizontal
Field strength　　　　　 ~500[Gauss]　　　　　　 – 1500 [Gauss]
Filling factor high (> 80 %) high (> 80%)