The Hinode XRT: Overview

1
The Hinode XRT Overview

• Leon Golub
• Smithsonian Astrophysical Observatory
• With contributions by Ed DeLuca, Mark Weber,
  Jonathan Cirtain, Kathy Reeves, Trish Jibben
• and the entire U.S. and Japanese Team

2
Mission Overview

• Hinode is an international collaboration between
  Space Agencies of Japan, the USA, the UK and
  Europe.
• It contains three instruments for coordinated
  observations to follow the generation, transport
  and dissipation of magnetic energy from the
  photosphere to the corona
• SOT a high resolution optical telescope that
  provides spectrally resolved images, Dopplergrams
  and vector magnetograms
• XRT A high resolution X-ray telescope that
  provides coronal temperature and density maps
• EIS An EUV imaging spectrometer that provides
  spatially resolved high resolution spectra.

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The Hinode Spacecraft

• The Hinode spacecraft is built around the
  optical telescope assembly (OTA).
• The focal plane package (FPP) of the OTA, the XRT
  and EIS are strapped to the sides of the OTA.
• The payload has a dry weight of 875 kg, the
  solar arrays provide 1000 w of power and the
  telemetry systems has a downlink capability of
  4.2 Mbps.
• ESA is providing 15 contacts per day from
  Svalbard to supplement the four daily passes at
  Kagoshima for a total of 7 GB per day.

Two Views of Hinode
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The Focal Plane Package
The FPP contains three instruments SP, BFI and
NFI. Dimensions 1.63 x 0.65 x 0.37 m3 Mass
48.4 kg

• The Spectropolarimeter (HAO) records full Stokes
  profiles of the magnetic field
• Slit Width 1.6 x 164 arcsec2
• Spectral Range 6302.05Å
• Spectral Resolution 25 mÅ
• Polarimetric Accuracy 104
• The Broad Band Filter Imager retains the highest
  spatial resolution (0.053 pixels) for photo and
  chromospheric imaging in six bands, 380 670 nm
• The Narrow Band Filter Imager measures vector
  magnetic fields and Dopplergrams using a tunable
  filter
• Spectral Coverage 5170 6570 Å
• Magnetic Sensitivity 5 G (long) 50 G (trans)
• Doppler Velocities 50 100 ms-1

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The EUV Imaging Spectrometer

• The EIS is a joint effort between MSSL and NRL.
• EIS provides temperature and density diagnostics
  of coronal and transition region plasmas and will
  attempt to detect reconnection flows.
• Properties
• Wavelengths 170-210 Å, 250-290 Å
• Resolution Spatial 1.0 arcsec pixel Spectral
  2.23 mÅ/pixel
• Slits1 x 512 and 2 x 512 arcsec2
• Slot 40 x 512 and 250 x 512 arcsec2

Final Preparations for EIS
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The X-Ray Telescope

• The telescope is a modified Wolter I with a 35 cm
  aperture and a 2.71 m focal length. It has
  on-orbit focus adjustment and provides a flare
  flag to alert the other instruments.
• Properties
• Angular Resolution 1 arcsec pixels
• Encircled Energy 50 within a 1 arcsec diameter
  circle at 0.523 KeV
• Improved temperature sensitivity over the range
  from 130 MK using a back thinned 2048x2048 CCD

Length 3.0 m, Diameter 0.42 m (max), Mass 48.4 kg
XRT Point Spread Function 50 Power Within One
Pixel
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Comparative Fields of View
EIS can independently offset along the EW axis.
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XRT Science Goals

• Coronal Mass Ejections
• Large field of view
• Coronal Heating
• High spatial resolution
• Reconnection and Jets
• Broad T-coverage
• Flare Energetics
• High time resolution
• Large dynamic range
• Photospheric-Coronal Coupling
• Coordination with SOT and EIS

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XRT Observation Modes

• Dynamics
• Rapid evolution associated with reconnection and
  plasma instabilities
• High Cadence
• Energetics
• The thermal evolution of structures heating
  cooling
• The emission measure evolution of structures up
  flows down flows
• Multiple filters
• Topology
• Identify the magnetic connections that control
  the heating and dynamics
• Large FOV, long and short exposures

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XRT First Light
28 October 2006
Hinode XRT Quiet Sun
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28 October 2006
Hinode XRT False Color
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A typical corona (QS small AR) requires gt104
dynamic range
Combined 4s 0.5s XRT exposures, Thin Al filter.
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TRACE and XRT are Complementary
TRACE 173Å 11/13/06
XRT Thin Al 11/13/06
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XRT Sees Fine Detail in ARsThe High Temperature
Corona is NOT Fuzzy!
1 arcmin
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B vs. X
MDI Magnetogram
XRT Thin Ti, 1 sec., 11/04/06
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XRT works with EIS for combined diagnostics
EIS 40 Slot
??? XRT ??
XRT
Fe XV 284
He II 256
EIS Spectrum
??(nm)
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XRT Combines With SOT for Photosphere/Corona
Connectivity Studies
XRT v. SOT G-band 11/14/06 B bifurcation over
light bridge
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XRT Shows Extent of Structure Surrounding ARs
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Detailed views of AR from XRT
Small AR near CMP
Thin Al/Poly 1 sec
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Filament/Prominence Studies Cavity Structures
Seen at Limb
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Transit of Mercury (Useful for finding the best
focus)
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Synoptic Sun-Center Program 5-min cadence, 8-hr
duration
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Quiet Sun XBP Studies30-sec cadence, 12-hour
duration
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Coronal Dynamics in XRT
5-min cadence, 12-hour duration
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Downflows Seen in Flares
Note highly sheared inner and unsheared outer
loops in flaring region.
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Growth of Postflare Cusp
Note downward-moving cooling fronts.
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Flare of 17-DEC-2006

• EIS 256 x 256 raster - 1 slit
• He II (log T 4.9) and ions for
• 6.0 lt log T lt 6.7
• Bi-directional Doppler shifts
• seen in the loop-top source

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EIS view at limb
TRACE movie
EIS movie
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Some flares show unexpected behavior
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Combined SOT and XRT Observations
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Extensive Structure Seen Above ARs
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Does XRT See Slip-Running Reconnection?
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Polar JetsNumerous Jet-like Events Observed
Image Cadence 30 sec.
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LEFT XRT Polar Jet movie RIGHT Shimojo,
M., and Shibata, K., ApJ 542, 1100 (2000). From
the Hudson Solar Cartoon Archive
(http//solarmuri.ssl.berkeley.edu/hhudson/cartoo
ns/overview.html)
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Coronal Dynamics in XRT North Polar XBP and Jets
11/23/06 Thin Al/Poly 4s. exp. 30-sec cadence,
7-hour duration
Mass loss estimate Np1037 per event Event
frequency 10/hr Net flux gt1012 p/cm2/s Avg.
solar wind flux 1013 p/cm2/s
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Combined EIS/XRT Polar Jet Obs
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Access to Hinode data

• Chief Coordinators
• John Davis (john.m.davis_at_nasa.gov)
• Tetsuya Watanabe (watanabe_at_uvlab.mtk.nao.ac.jp)
• Science Schedule Coordinators (in U.S.)
• SOT T. Berger (berger_at_lmsal.com)
• XRT L. Golub (golub_at_cfa.harvard.edu)
• EIS J. Mariska (mariska_at_nrl.navy.mil)
• L. Culhane (jlc_at_mssl.ucl.ac.uk) in Europe
• XRT Observing (XOB) Proposals http//solar.physic
  s.montana.edu/HINODE/XRT
• Master Schedule will be placed on line
• Hinode-timeline.xls