JOP181 Fine Magnetic Structures as the Origin of Coronal Heating and Activities Short title: Fine Magnetic Structures/Coronal Heating Received: 11 May 2005 Revised: 1 June 2005 - T. Tarbell added, TIP -> TIP2 in VTT section Revised: 2 July 2005 - CDS details (e.g. study name) added AUTHORS: Y. Katsukawa, T. Shimizu, and S. Tsuneta (NAOJ) V. Martinez Pillet (IAC) T. Tarbell (LMSAL) INSTRUMENTS: SoHO CDS, EIT, and MDI TRACE GBO SST (La Palma), DOT (La Palma), and VTT (Tenerife) DATES: Jul. 3 - 14, 2005 SCIENCE OBJECTIVES: We propose to observe evolution and properties of small-scale magnetic features with SST, VTT, and DOT. The primary target in this observing run is inside of or around a sunspot, where various magnetic features and their dynamical behavior, such as interlaced penumbral fields and moving magnetic features (MMFs), are well observed. Simultaneous observations with TRACE and SOHO provide coronal features, such as coronal loops, moss structures, and microflares, associated with the magnetic fields at the photosphere/chromosphere. We expect that this program gives us the clue to clarify the causal relationship between the photospheric/ chromospheric magnetic signatures and the coronal heating and dynamics. SCIENTIFIC JUSTIFICATION: Recent observations of the solar corona with Yohkoh, SOHO, and TRACE show that the corona is quite non-uniform and has a variety of temperatures (1-5MK) and transient phenomena (microflares, X-ray jets, etc.). The main driver of the coronal heating and activities are magnetic fields in the photosphere. Magnetic fields are not uniformly distributed in the photosphere, but consist of concentrated fine magnetic elements whose spatial scale is much less than one arcsec. Thus, it is essential to measure the magnetic field vectors of the magnetic elements and to track their evolution in revealing the magnetic connectivity between the photosphere/chromosphere and the corona. In this campaign, we perform a simultaneous observation of (1) spatial distribution and temporal evolution of photospheric/ chromospheric fine features with SST and DOT, (2) vector magnetic fields in the photosphere and chromosphere with TIP on VTT, and (3) coronal quasi-steady structures (coronal loops and moss) and transient phenomena (e.g. microflares and jets) with TRACE and SOHO. We focus on the two topics in this program: (1) magnetic properties at the footpoints of the coronal loops, and (2) coronal activities caused by satellite spots and MMFs around a sunspot. EUV observations with TRACE show that 1 MK coronal loops emerging from sunspots form a fan-like structure. The footpoints of the loops are not uniformly distributed in a sunspot, but have preferred locations. Katsukawa (2004) compares the footpoint positions of the coronal loops with the photospheric vector magnetic fields derived with the Advanced Stokes Polarimeter (ASP), and shows that the footpoints of the cool loops are associated with the interlaced magnetic structure between umbra and penumbra. He suggests that built-in current sheets in the discontinuous magnetic structure release their magnetic energy through magnetic reconnection, leading to the heating of the base of the corona. The simultaneous measurement of the photospheric and chromospheric magnetic fields by TIP on VTT provides us with unique information on 3-dimensional structure located at the footpoints of the coronal loops. We will derive the flow pattern in the sunspot by applying feature tracking to the high-resolution image sequences obtained with SST and DOT, and investigate spatial correlation between the footpoints of the coronal loops and the photospheric flow pattern. Moving magnetic features (MMFs) are well observed in a moat region around a well-developed sunspot. Satellite spots are formed around the outer boundary of the moat region. Yohkoh soft X-ray observations show that microflares and X-ray jest occurs preferentially around leading sunspots. We plan to investigate three dimensional magnetic structures of MMFs, moat regions, and satellite spots from a simultaneous observation of the photospheric and chromospheric lines with TIP on VTT. MMFs move straight to the outer boundary of the sunspot moat region although granules have random motions. It is important to investigate the granular motion in the path of MMFs in order to understand the origin of outward straight motion of MMFs. The observation with SST and DOT are necessary to obtain their motions in detail owing to their high spatial and temporal resolution. The study of MMFs and satellite spots is also important in understanding a decaying process of sunspots. OPERATIONAL CONSIDERATIONS: Selection of the target active region will be made one day in advance to allow SOHO and TRACE time line preparation as usual. Active region near central meridian are preferred to minimize projection effects in the observation of vector magnetic fields. Following the same region for several days in a row is generally desirable. The hours of the observation in Canaries will be approximately 8 - 17 UT, with the best seeing conditions probably between 8-12 UT. OBSERVING SEQUENCES: SST -- Multi-frame blind deconvolution (MFBD) set-up in G-band and Ca-II imaging. Fe I 6302 magnetograms and FeI 5576 Dopplergrams with the SOUP tunable filter. DOT -- Multi-wavelength speckle imaging in H-alpha, G-band, CaII H, and red/blue continuum. VTT -- He I 10830 A and Fe I 6302 A spectro-polarimetry by Tenerife Infrared Polarimeter (TIP2) and Polarimetric Littrow Spectrograph (POLIS) MDI -- Full-disk magnetograms and Dopplergrams with 1 min cadence EIT -- Full-disk 195A images with 12-min cadence (195A CME watch) CDS -- 4'x4' NIS raster observation with the 4'' slit, and it takes 1hr 25mins for one raster. There are 20 wavelength windows, containg a large number of lines from the transition region through the corona. This study named STRONGLI is almost the same with ARDIAG_2 except that it includes a O III line without the density diagnostics. TRACE -- High quality, medium cadence 171 A images are the primary observation, with frequent context images in white light and 1600 A.