EIS - MSSL/NRL EUV Imaging Spectrometer SOT - ISAS/NAOJ Solar Optical Telescope XRT - SAO/ISAS X-ray Telescope FPP - Lockheed/NAOJ Focal Plane Package
Mission Characteristics Launch date: August 2006 Launch vehicle: ISAS MV Mission lifetime: 3 years Orbit: Polar, sun synchronous Inclination: 97.9 degrees Altitude: 600 km. Mass: 900 kg
Large Effective Area in two EUV bands: Å and Å –Multi-layer Mirror (15 cm dia ) and Grating; both with optimised Mo/Si Coatings –CCD camera; Two 2048 x 1024 high QE back illuminated CCDs Spatial resolution: 1 arcsec pixels/2 arcsec resolution Line spectroscopy with ~ 25 km/s pixel sampling Field of View ： –Raster: 6 arcmin×8.5 arcmin; –FOV centre moveable E – W by ± 15 arcmin Wide temperature coverage: log T = 4.7, 5.4, K Simultaneous observation of up to 25 lines EIS - Instrument Features
Slit Exchange Mechanism Primary Mirror Entrance Filter Concave Grating Filter CCDs Shutter 1939 mm 1440 mm 1000 mm EIS Optical Diagram Grating Front Baffle Entrance Filter Primary Mirror CCD Camera
Installation of Key Subsystems in Structure Primary Mirror Grating Entrance Filter Holder Dual CCD Camera Filter Holder Installed EIS Instrument Completed
Observables Observation of single lines –Line intensity and profile –Line shift ( ) → Doppler motion –Line width ( w) and temperature → Nonthermal motion Observation of line pair ratios –Temperature –Density Observation of multiple lines –Differential emission measure ww
Emission Lines on EIS CCDs 1024 pixels
Four slit/slot selections available EUV line spectroscopy - Slits - 1 arcsec 512 arcsec slit - best spectral resolution - 2 arcsec 512 arcsec slit - higher throughput EUV Imaging – Slots –Overlappogram; velocity information overlapped –40 arcsec 512 arcsec slot - imaging with little overlap –250 arcsec 512 arcsec slot - detecting transient events Slit and Slot Interchange
EIS Field-of-View (FOV) 360 512 EIS Slit Maximum FOV for raster observation 512 900 Raster-scan range Shift of FOV center with coarse-mirror motion 250 slot 40 slot 512
EIS Sensitivity IonWavelength (A) logTN photons ARM2-Flare Fe X Fe XII / /21105/130 Fe XXI Fe XI / / 15110/47 Fe XXIV 10 4 Fe XII Ca XVII 10 3 Fe XII Fe XII / /16538/133 Fe XIII Fe XIII Fe XIII / /2038/114 Detected photons per 1 1 area of the sun per 1 sec exposure. IonWavelength (A) logTN photons ARM2-Flare Fe XVI Fe XXII Fe XVII Fe XXVI 10 3 He II 10 3 Si X Fe XVI Fe XXIII 10 3 Fe XIV Fe XIV Fe XIV Fe XV 10 3 AR: active region
Expected Accuracy of Velocity Doppler velocity Line width Bright AR line Flare line Photons (1 1 area) -1 sec -1 Photons (1 1 area) -1 (10sec) -1 Number of detected photons
Processed Science Data Products Intensity Maps (T e, n e ):Intensity Maps (T e, n e ): – images of region being rastered from the zeroth moments of strongest spectral lines Doppler Shift Maps (Bulk Velocity):Doppler Shift Maps (Bulk Velocity): – images of region being rastered from first moments of the strongest spectral lines Line Width Maps (NT Velocity):Line Width Maps (NT Velocity): – images of region being rastered from second moments of the strongest spectral lines Norikura coronagraph observations of all three of these parameters
The first 3 months…. atial determination of evaporation and turbulence in a flareFlare trigger and dynamics: Spatial determination of evaporation and turbulence in a flare patial determination of the velocity field in active region loopsActive region heating: Spatial determination of the velocity field in active region loops easurement of intensity and velocity field at a coronal hole boundaryCoronal Hole Boundaries: Measurement of intensity and velocity field at a coronal hole boundary etermination of the relationship between different categories of quiet Sun events.Quiet Sun Brightenings: Determination of the relationship between different categories of quiet Sun events.
Active Regions connect the photospheric velocity field to the signatures of coronal heating. This will allow us to determine the dominant heating mechanism in active regions, and will be extended to other coronal brightenings. search for evidence of waves in loops and make use of observations for coronal seismology study dynamic phenomena within active region loops.
Quiet Sun link quiet Sun brightenings and explosive events to the magnetic field changes in the network and inter-network to understand the origin of these events. determine the variation of explosive events and blinkers with temperature. Search for evidence of reconnection and flows at junctions between open and closed magnetic field at coronal hole boundaries. Determine the impact of quiet Sun events on larger scale structures within the corona. Determine physical size scales using density diagnostics.
Solar Flares determine the source and location of flaring and identify the source of energy for flares. EIS will measure the velocity fields and observe coronal structures with temperature information. Hence will allow us to address the trigger mechanism. detection of reconnection inflows, outflows and the associated turbulence which play the pivotal role in flare particle acceleration.
Coronal Mass Ejections determine the location of dimming (and the subsequent velocities) in various magnetic configurations allowing us to determine the magnetic environment that leads to a coronal mass ejection. The situations to be studied include filaments, flaring active regions and trans-equatorial loops.
Large Scale Structures determine the temperature and velocity structure in a coronal streamer determine the velocity field and temperature change of a trans-equatorial loop, and search for evidence of large-scale reconnection. Using a low-latitude coronal hole, search for evidence of the fast solar wind.
Information is maintained on our website; The EIS science planning guide shows details of the 3 month plan studies including line choices, which slit/slot, FOV etc. The planning software will be released into SSW in the autumn. Quicklook software etc. is already in SSW. Details are on the website. The next solar-B science meeting will be in Kyoto in November.