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Explore magnetic reconnection and particle acceleration on the Sun using Hinode XRT for broad temperature coverage and high spatial resolution observations.
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XRT Magnetic Reconnection and Particle Acceleration on the Sun Using the Hinode X-ray Telescope (XRT) Kelly E. Korreck Harvard-Smithsonian Center for Astrophysics Cambridge, MA Smithsonian Astrophysical Observatory
Outline • Reconnection and the Sun • Macrophysics versus Microphysics • XRT and Reconnection • Polar Jets • XRT and particle acceleration • On disk loops • “Shrinking” limb loops • Future Prospects for Solar Reconnection Studies Smithsonian Astrophysical Observatory
Yohkoh Solar Missions and Reconnection Courtesy of JAXA Cusp structure at the top of a flare loop discovered by Yohkoh , and hard X-ray sources above a flare loop (the contour lines in white) . These discoveries are regarded evidence for magnetic reconnection. Smithsonian Astrophysical Observatory
UVCS CME results: Reconnection physics • On several occasions, narrow brightening in Fe XVIII (Te ~ 6 MK) appears in the probable location of a current sheet. • Lin et al. (2005) also saw Lyman alpha “closing down” in the sheet: one can measure reconnection rate (Vin / Vout ) Slide Courtesy of Steve Cranmer
Science Questions to Address with Hinode Data The three instruments are designed to provide coordinated observations that will follow the generation, transport and ultimate dissipation of magnetic energy from the photosphere to the corona. • Coronal Heating • Reconnection, particle acceleration,and jets • Flare Energetics • Coronal Mass Ejections Smithsonian Astrophysical Observatory
HINODE (Solar-B) Sept 22, 2006 JAXA, NASA, & PPARC • Solar Optical Telescope (SOT) • Magnetic fields, photosphere, & Chromosphere (LM, NAOJ) • Broad and Narrow Band Filters • EUV Imaging Spectrometer (EIS) • Transition Region, Corona (170-210 Å & 250-290 Å) (NRL, MSSL) • X-ray Telescope (XRT) • Corona, Soft X-rays (6-200 Å) • G-band 4305 Å • SAO & JAXA Uchinoura Space Center, Japan Smithsonian Astrophysical Observatory
XRT • Wolter-I grazing incidence mirror with co-focal visible light optics • 2048x2048 back-illuminated CCD 13.5 µm pixel size FOV 34 x 34 arcmin Plate scale 1”/pixel Smithsonian Astrophysical Observatory
XRT Science Goals for Reconnection Studies Reconnection and Jets • Where and how does reconnection occur? Is it related to slow CMEs? • High time resolution • Large FOV • What are the relations to the local magnetic field? • High spatial resolution • Broad temperature coverage • Coordinated observing with EIS/SOT Smithsonian Astrophysical Observatory
Al Poly C Poly Be Thin Smithsonian Astrophysical Observatory
SXT & XRT Smithsonian Astrophysical Observatory
SXT & XRT Smithsonian Astrophysical Observatory
XRT & SXI Smithsonian Astrophysical Observatory
Magnetic Energy in X-rays MDI Magnetogram XRT Thin Ti, 1 sec., 11/04/06 Smithsonian Astrophysical Observatory
TRACE 11/13/06 XRT 11/13/06 TRACE & XRT are Complimentary Smithsonian Astrophysical Observatory
Pre-flare Configuration 12/14/2006 10:54 UT ~107 km TRACE 195 XRT thin-Be Smithsonian Astrophysical Observatory
Post-flare Configuration 12/15/2006 01:33 UT TRACE 195 XRT thin-Be Smithsonian Astrophysical Observatory
Coordinated XRT-SOT Flare Observations Smithsonian Astrophysical Observatory
AR 0930 - 2 X-flares! Smithsonian Astrophysical Observatory
Limb Jets:Reconnection Loop Height of ~7Mm Extent of Jet~96 Mm T~2MK Smithsonian Astrophysical Observatory
Reconnection in Jets thus far • Yohkoh started matching corona loops structures with acceleration sites • Utilized an observation of a loop on the limb as a reconnection site. • Study the outflow from this region using EIS, SOT and XRT- Results to be soon published in PASJ by Cirtain and Savcheva Smithsonian Astrophysical Observatory
Electron sites (contours) Solar limb Ion sites (circles) Hurford et al, ApJ, 595, L77 (2003) Smithsonian Astrophysical Observatory
Al_med C_poly Al_poly Be_med Be_thin Smithsonian Astrophysical Observatory MDI Magnetogram
171 A 195 A Complimentary Data 284 A TRACE adds information about structure as well as more filters for temperature analysis Smithsonian Astrophysical Observatory
Determining Temperatures • Useful for understanding location of flare heating, cooling processes in flares and solar eruptions. • Method 1 - Filter Ratios • Method 2 - Differential Emission Measure Analysis Smithsonian Astrophysical Observatory
Observations Courtesy of K. Reeves Smithsonian Astrophysical Observatory
Filter Ratio Analysis Smithsonian Astrophysical Observatory
Filter Ratios * * * Smithsonian Astrophysical Observatory
Filter Ratio Analysis Smithsonian Astrophysical Observatory
DEM Analysis • Method developed by M. Weber, E. DeLuca, L. Golub (see L. Golub et al., 2004) • DEM determined by a least-squares minimization algorithm • Random error generation for determining DEM errors Smithsonian Astrophysical Observatory
DEM Analysis ambient corona flare loop Smithsonian Astrophysical Observatory
DEM Analysis ambient corona flare loop Smithsonian Astrophysical Observatory
RHESSI Data Smithsonian Astrophysical Observatory
Conclusions so far... • Post-flare loops contain multi-thermal plasma, ambient corona is closer to two-temperature plasma, we need to pick out the accelerated particles • Hot plasma is not well determined using this method with only XRT data • RHESSI data should be useful in constraining high temperature plasma Smithsonian Astrophysical Observatory
Future • Coordinated SOT/XRT/EIS on limb as well as on disk reconnection site observations to get high time cadence and many filter (temperature) observations • Use Rhessi data to understand the characteristics of the electrons in the process • DEM and filter ratio temperature determination • Modeling of energies available for particle acceleration for these reconnection sites Smithsonian Astrophysical Observatory
Access To Hinode Data • Chief Coordinators: • John Davis (john.m.davis@nasa.gov) • Tetsuya Watanabe (watanabe@uvlab.mtk.nao.ac.jp) • Science Schedule Coordinators (in U.S.): • SOT: T. Berger (berger@lmsal.com) • XRT: L. Golub (golub@cfa.harvard.edu) • EIS: J. Mariska (mariska@nrl.navy.mil) • XRT Observing (XOB) Proposals: http://solar.physics.montana.edu/HINODE/XRT • XRT Data release on Virtual Solar Observatory on May 27, 2007 Smithsonian Astrophysical Observatory