Hinode Coordinated Observations: Solar Flare Production

1. Hinode Coordinated Observations: Solar Flare Production • Question: Do photospheric dynamics play an important role in the production of great solar flares? • Formation of non-potential magnetic field that provides the energy to drive the flare may be driven by photospheric flows • Observations from Hinode/SOT and Hinode/XRT: • High-speed photospheric flows (approaching sonic velocities) persist for hours before and after flare • Location of flare ribbons determined from SOT/BFI Ca II images and XRT • Flows appear to be aligned along the horizontal magnetic field at the polarity inversion line between the flare ribbons • Flows co-spatial with strong fields (1200-1400 Gauss) SOT/SP magnetic field vector SOT/SP Doppler velocity • Implication: • High-speed photospheric flows may produce the build-up of magnetic shear leading to the flare instability Contributed by the Hinode/SOT team through the Lockheed Martin Solar and Astrophysics Laboratory

2. Hinode Coordinated Observations: Solar Cycle Question: How does the weakest component of quiet Sun flux vary with the solar cycle? • Hinode SOT Observations: • Monthly “HOP 79” observations from pole-to-pole since 2008 • SOT Spectro-Polarimeter has uniquecapability to observe very weak flux at high resolution – permits separation of strong-field “network” regions from the very weak signal “internetwork” • With a very few exceptions, HOP 79 observations observe quiet Sun Left image: All measured HOP 79 flux versus solar disk angle (North positive) and time. Clear presence of stronger flux in the sunspot belt, and increase of flux with rise of solar cycle in 2010 and later. Right image: Same as left image, except excluding the strong “Network” flux. • Findings: • The weak internetwork flux has very little, if any, dependence on the solar cycle • No association with the solar cycle indicates an origin of the pervasive weak internetwork flux that is distinct from that of the network and active region flux • Results strongly support the hypothesis of a small-scale turbulent dynamo operating in the upper solar convection zone Contributed by the Hinode/SOT team through the Lockheed Martin Solar and Astrophysics Laboratory

3. Hinode Coordinated Observations: Polar Jets OBSERVATIONSThree very large solar jets were observed during a three-week period in September 2007 with Hinode XRT (Polar Region Observation Campaign, HOP 02), coronagraph LASCO C2, STEREO COR2, and SMEI. [Past coordinated observations with external observatories continuing to produce results!] DATA ANALYSIS i) Hinode XRT high-cadence data: Timing and X-ray brightness coincident with the SMEI analysis period ii)LASCO and STEREO: visualization of the present/depleted material during jet events plus tracking through heliosphere. iii)SMEI: 3D analysis of volume, total density, and energy of the outward flow of the jet response at different solar distances • RESULTS • High-speed responses show a close association in onset time when traced back with constant speed to the Hinode X-ray jet peak brightness • Propagated outward at these speeds the jet responses are also observed in SMEI 3D reconstructions. • The jets may contribute ∼3.2% of the mass of solar wind and ∼1.6% of the solar wind energy, by comparing our measurements to Ulysses polar solar wind values. Outward motion of two the coronal responses to the jets observed by Hinode XRT on September 2007. The outward speed for the other one is ~420 km/s. Contributed by the Hinode/SOT team through the Lockheed Martin Solar and Astrophysics Laboratory