Bastian-Solar Radiophysics of the...

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Solar & HeliosphericRadiophysics of the Future

T. S. BastianNRAO

• Science drivers• Observations & techniques• New instrumentation

Science Issues (~10 yrs)• Magnetic energy storage and release

flares and CMEs

• Particle acceleration

SEPs

• Wave dissipation

Corona/Chromosphere/Solar Wind

• Space weather prediction

from L. Lanzerotti

Long duration flare observed on west limb by Yohkoh and the Nobeyamaradioheliograph on 16 March 1993.

Y. Hanaoka Aschwanden & Benz 1997

Plasma rad.

Thermal f-f

Gyrosynchrotron

Isliker & Benz 1994

Reverse slope type IIIdm radio bursts

17 GHz intensity 17 GHz circ. pol. 34 GHz intensity

Magnetic loop in the solar corona illuminated by gyrosynchrotronemission from nonthermal electrons.

Nobeyama RH

TRACE 195 A: 21 April 2002

Bastian et al. (2001)

Noise storm

Bastian et al. (2001)

300.335 x 1052212.8-1.074

1900.696.5 x 106219.52.40.033

2651.031.35 x 107218.52.050.542

3301.472.5 x 1072341.451.811

LoS α Rsun φ (deg) ne (cm-3) B(G) νRT (MHz)

Török & Kliem (2005) Linton & Loncope (2005)

New Observables/Techniques

Time resolved, wide-band, imaging spectroscopy (FASR)coronal magnetography, magnetic energy release, electron distribution function & evolution, shock & beam tracers

Scintillation tomography (MWA, LWA)IP Spatial spectrum electron density turbulence, IP macrostructures (CIRs), IP magnetic field constraints (FR)

Lee et al 1998

Patzöld et al. 1987

Faraday rotation measurements using a radio beacon on Helios

Patzöld et al. (1987)

Jackson et al. 2001

Tomographic reconstruction of recurrent structures in the inner heliosphere using observations of inter-planetary scintillation (IPS).

New Instrumentation• Frequency Agile Solar Radiotelesope (FASR)• Mileura Widefield Array (MWA)• Long Wavelength Array (LWA)

• Solar Imaging Radio Array (SIRA) • Lunar based opportunities?

May 12: NASA RFI - “Developing a Strategy for Future Ecploration of the Moon and Beyond”

July 28: ROSES-2006, NASA establishes a new program element in Appendix E.4 entitled "Concept Studies for Lunar Sortie Science Opportunities (LSSO)."

FASR is a solar-dedicated radio telescope designed to perform dynamic broadband imaging spectroscopy.

It will do so with time resolution, frequency resolution, and angular resolution commensurate with the physical phenomena of interest.

Frequency Agile Solar Radiotelescope

FASR Specifications

~4.5 kmFootprint

>0.5 degField of View

20/ν9 arcsecAngular resolution

Stokes IV(QU)Polarization

A: 2 m B: 6 m C: LPDA or similar

Size antennas

A (2-20 GHz): ~100 B (0.25-3 GHz): ~80C (50-300 MHz): ~60

Number antennas

100 msTime resolution

1%Frequency resolution

50 MHz - 20 GHz30 MHz – 30 GHz (goal)

Frequency range

FASR A: ~3-30 GHz

FASR B: ~0.3-3 GHz

FASR C: ~30-300 MHz

(a milli-SKA!)

FASR Key ScienceNature & Evolution of Coronal Magnetic FieldsMeasurement of coronal magnetic fields Temporal & spatial evolution of fieldsRole of electric currents in coronaCoronal seismology

Physics of FlaresMagnetic energy releasePlasma heatingElectron acceleration and transportOrigin of SEPs

Drivers of Space WeatherBirth & acceleration of CMEsProminence eruptionsOrigin of SEPsFast solar wind streams

FASR Science (cont)The “thermal” solar atmosphere

Coronal heating - nanoflaresThermodynamic structure & dynamics Formation & structure of filaments

Solar WindBirth in network Coronal holesFast/slow wind streamsTurbulence and waves

Synoptic studiesRadiative inputs to upper atmosphereGlobal magnetic field/dynamoFlare statistics