1 / 30

Contents

Contents. The Project. Introduction. SMART 1:. XSM DCIXS. GOES. Preliminary Results. Questions. The Project.

amina
Download Presentation

Contents

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Contents • The Project • Introduction • SMART 1: XSM DCIXS • GOES • Preliminary Results • Questions

  2. The Project An investigation to determine whether the two broad band X-ray measurements from the NASA geostationary operational environmental satellite (GOES) can reproduce the full X-ray spectrum of the Sun

  3. The Sun The Sun has a huge impact on life upon Earth!!!

  4. The Suns Activity A more serious side….. • Disrupt radio transmissions • Cause power blackouts • Damage satellites • Effects astronauts and airline pilots New York during power blackout in 2003

  5. Solar Flares • Sudden release of energy from the Sun • Energy appears as radiation over a range of wavelengths • …but also as mass, particle, wave and shock wave motions

  6. The Solar Cycle • Is 11 years in duration • 22 years until magnetic polarity restored • Poloidal field is converted into a toroidal field by differential rotation • Driven by internal magnetic field in the tachocline

  7. Activity of the Sun Video Clips from SOHO Extreme Ultraviolet Imaging Telescope

  8. The Sun as an X-ray Source Thermal radiation • At surface temp of sun (~6000K) X-ray emission should be weak • But solar corona is much hotter (>1,000,000K) Soft X-ray image from GOES 12 SXI taken on 15th November 2005 Very little intensity in X-ray wavelengths The black part of the image represents no X-ray source

  9. The Sun as an X-ray Source • Soft X-ray continuum caused, at least partly, by Bremmstrahlung radiation • Hard X-ray emission of flares would require much more energetic conditions • Assuming an energy distribution of a hot gas, maxwellian distribution, temperatures would have to be >108K ….. What produces the hard x-ray emission during a solar flare???

  10. Hard X-Ray Emission Reconnection Must be a process associated with the flare Magnetic field lines Solar surface Magnetic Reconnection • Two volumes containing oppositely directed fields are brought in close contact • Current sheet has to exist at boundary • Small, local resistance leading to dissipation of current and heating • Magnetic field ‘diffuses away’ • Energy in current appears as heat/ acceleration of particles

  11. Soft X-Ray Line Spectrum • Soft X-Ray spectrum consists of lines • Temperature is so high that atoms are stripped of n=2 & n=3 electrons • Remaining bound electrons excited by collisions with free electrons • Photons then emitted by downward transition of excited, bound electrons This produces resonance lines of Hydrogen and Helium like ions of abundant elements in the soft solar X-ray spectrum

  12. SMART-1 • To test new technology to be used on bigger projects • Primary objective – test electric primary propulsion • Successfully launched 27th September 2003 • Entered lunar orbit 15th November 2004

  13. D-CIXS • Demonstration of compact imaging X-ray spectrometer • Built to provide global coverage of the lunar surface in X-rays • Will give absolute measurements of elemental abundances

  14. XSM • X-Ray Solar Monitor • Used to callibrate D-CIXS, but also used for independent science • 105 degree field of view • Energy range 1-20 keV • Energy resolution of 250 eV at 6 keV • 512 channels, 40eV/channel

  15. XSM • More info on XSM

  16. GOES • Geostationary Operational Environmental Satellite • GOES-1 launched 16th October 1965 • GOES-12 is newest addition, launched 23rd July 2001 • Weather satellitte

  17. 0.5 – 3 Å • 1 – 8 Å Solar Environment Monitor (SEM) 1) Energetic particle sensor (EPS) 2) two magnetometer sensors 3) Solar x-ray sensor (XRS) • XRS is an X-ray telescope • Measures solar X-ray emission in two ranges:

  18. Method Work completed • Familiarisation with IDL and project literature • Calibration and background correction of XSM spectra • Acquisition and interpolation of GOES solar X-ray flux

  19. Preliminary Results: GOES

  20. GOES Results

  21. GOES Results

  22. Preliminary Results: XSM

  23. XSM Results

  24. XSM Results

  25. XSM Results

  26. XSM Results

  27. XSM Results

  28. Future Work Work still to be completed • Correction for position of the Sun as seen by XSM • Acquisition and averaging of the GOES solar X-ray flux • Determination of correlation between XSM and GOES data • Advanced work depending on the correlation outcome

  29. Preliminary Presentation THE END!! QUESTIONS???

More Related