Preliminary PresentationBy Matthew Lewis

2nd December 2005

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Contents

•Introduction•The Project

•SMART 1: XSMDCIXS

•Preliminary Results•Questions

•GOES

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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

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The Sun

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

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The Suns Activity

• Disrupt radio transmissions

• Cause power blackouts• Damage satellites• Effects astronauts and

airline pilots

A more serious side…..

New York during power blackout in 2003

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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

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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

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Activity of the SunVideo Clips from SOHO Extreme Ultraviolet Imaging Telescope

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The Sun as an X-ray Source

• At surface temp of sun (~6000K) X-ray emission should be weak

• But solar corona is much hotter (>1,000,000K)

Thermal radiation

Soft X-ray image from GOES 12 SXI taken on 15th November 2005

The black part of the image represents no X-ray source

Very little intensity in X-ray wavelengths

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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???

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Hard X-Ray EmissionMust be a process associated with the flare

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

Magnetic field lines

Solar surface

Reconnection

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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

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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

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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

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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

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XSM

• More info on XSM

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GOES• Geostationary Operational

Environmental Satellite• GOES-1 launched 16th

October 1965• GOES-12 is newest

addition, launched 23rd July 2001

• Weather satellitte

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Solar Environment Monitor (SEM)

1) Energetic particle sensor (EPS)2) two magnetometer sensors3) Solar x-ray sensor (XRS)

•XRS is an X-ray telescope•Measures solar X-ray emission in two ranges: 0.5 – 3 Å

1 – 8 Å

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Method

•Familiarisation with IDL and project literature

•Calibration and background correction of XSM spectra

•Acquisition and interpolation of GOES solar X-ray flux

Work completed

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Preliminary Results: GOES

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GOES Results

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GOES Results

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Preliminary Results: XSM

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XSM Results

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XSM Results

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XSM Results

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XSM Results

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XSM Results

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Future Work

•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

Work still to be completed

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Preliminary Presentation

THE END!!

QUESTIONS???