1. 1. Twist propagation in Hα surges Patricia Jibben and Richard C. Canfield 2004, ApJ, 610, 1129 2. Observation of the Molecular Zeeman Effect in the G Band A.Asensio Ramos et al., 2004, ApJ, 611, L61 2004 Sep 27 雑誌会速報 J. Kiyohara

2. Twist propagation in Hα surges Patricia Jibben and Richard C. Canfield 2004, ApJ, 610, 1129 － The relationship between surge spin and the stored twist in the magnetic field was examined. － Hα spectroheliograms (Mees CCD Imaging Spectrograph) spectral range : Hα±10 Å 2”.3 pixel -1 spatial and 0.37 Å pixel -1 spectral resolution vector magnetogram (Haleakala Stokes Polarimeter) Fe I : 6301.5 and 6302.5 magnetogram － Active region selection criteria - change of the active region area ⊿ a/a>10% - δor βγδregion - relatively large area ( a > 500μh) - well sampled with MCCD and HSP - within ± 45°of central meridian → 396 surges were selected

3. velocity map white : red shift black : blue shift Hα map → handedness could be determined in 249 → 68% correlation between surge handedness and the hemisphere of the Sun Hα spectropheliograms and Doppler Shifts

4. HSP vector magnetograms and αmaps left : vector magnetogram right : αmap negative : dashed positive : solid α ＞ 0 : right-handed

5. － Most of the surges tend to occur near the edge of a sunspot and near a boundary separating opposite signs of α. － A correlation between the stored twist in the magnetic field at the point of origin and handedness of the surge spin at the 99% confidence level. Of all the observed surges, only 26 surges could be determined both the handedness of the surge and the sign of α at its point of origin.

6. Interpretation Magnetic reconnection of twisted magnetic flux with less twisted flux explains the correlation. right-handed left-handed － energy release will accompany reconnection, and brightenings are a common feature of the observed events. － if the reconnected field lines do not have the same twist per unit length, post-reconnection twist propagation will take place.

7. Observation of the Molecular Zeeman Effect in the G Band A. Asensio Ramos et al., 2004, ApJ, 611, L61 Photospheric bright points observed in G band are seen with very high contrast. → Theoretical investigation (Uietenbroek et al. 2004) → This paper shows － first observational study ( 4304 Å + 4312 Å ) NOAA0477 on 2003 Aug. 30 with ZIMPOL (Zurich Imaging Polarimeter) piezoelastic modulator + linear polarizer － radiative transfer calculations

8. Theoretical prediction of the G-band polarization in Sunspot calculation including both the atomic and CH lines calculation including only the CH lines calculation without including any stray-light contamination In one wavelength location near 4303 Å, the overlap of several magnetically sensitive and nonsensitive CH lines was predicted to produce a single-lobed Stokes V profile.

9. calculations observed V/I positive polarity observed V/I negative polarity

10. calculations observed V/I observed Q/I in penumbrae non negligible linear polarization

11. － The observed polarization profiles confirm the previous theoretical prediction of the Zeeman effect in the G band. － Non-negligible Linear polarization was detected in both umbrae and penumbrae. － preliminary comparison V/I amplitude is smaller than the theoretical prediction (2000G) → an indication of the presence of horizontal inhomogeneities in th photospheric regions of sunspot umbrae coexisting within the spatiotemporal resolution element of the observation. → these inhomogeneities might be associated with the multitude of umbral dots. → linear polarization signal observed in sunspot umbrae could be an indication that the umbral dot component has inclined magnetic fields. － The theoretical interpretation of observations of the Zeeman effect in the G band offers a new diagnostic window for exploring the thermal and magnetic structuring of the solar photosphere. conclusion