Solar System Science

Flares and Solar Energetic Particles

Terrestrial Gamma-Ray Flashes

Cosmic-ray interactions with Earth, Sun, Moon, etc.

Plans:Optimization of GLAST flare responseSolar Physics paper on GLAST capabilities

GLAST Solar Flare Response

GLAST launch late in solar minimum Rise in solar activity 2008-9; peak 2010-2014.(But remember 20 January 2005 flare—later discussion)

Possible Solar Flare Mode

Activate overall solar-flare capability when probability for X-class flare exceeds 5% in a 24 day period

GBM trigger:

Soft- spectrum burst detected <20 degrees from Sun; detectable flux > 1 MeV

GLAST action:

ACD veto disabled

Sun < 70 deg from Z-axis –

Data analyzed from 4 central towers below first 4(?) layers.Return to normal mode in 1000 s or when GBM solar-side BGO rate < R.

Sun >70 deg from Z-axis

Calorimeter trigger: lowered energy threshold (~100 MeV).Return to normal mode in 1000 s or when GBM solar-side BGO rate < R.

Hardest flare ever detected in space.(near solar minimum!!)

Milagro Observation of >10 GeV Particles from Sun on 20 Jan 2005

GOES proton data>10 MeV>50 MeV>100 MeV

Milagro scaler data> 10 GeV protons

~1 min rise-time

~5 min duration

Milagro Observed > 10 GeV from the Solar Energetic Particle events on

• 6 November 1997• 14 July 2000• 15 April 2001• 20 January 2005

2005 January 20 Gamma Ray Spectrum at Peak

Very hard accelerated particle spectrum, s ~ 2.2, from annihilation and neutron capture line comparison.

Lines??

RHESSI

Nuclear continuum dominates for hard spectra, masking the discrete lines. Just statistics or something

fundamental?

RHESSI

SMM

7:01 UT X7.1 N14W61

6.60 6.65 6.70 6.75 6.80 6.85 6.90 6.95 7.00UT (÷àñû è äî ëè ÷àñà) 20/01/2005

1E+0

1E+1

1E+2

1E+3

1E+4

1E+5

X è ãàììà (ÑÎÍÃ), 1/ñåê

Coronas-F Song

0.01 0.1 1 10 10010-6

1x10-4

10-2

100

102

104

0.1 1 10 100

0.1 1 10 10010-6

1x10-4

10-2

100

102

104

0.1 1 10 100

20 January, 2005 SONG

I II

E, MeV

F, cm

-2 s

-1 MeV

-1

III

E, MeV

IV

Pion peak?

Coronas observed pion radiation here.

Is the long 511 keV flux tail due to newly revealed radioactive material?

Terrestrial flashes observed by RHESSI (David Smith)

1 ms duration; associated with lightening (sprites); discovered by BATSE; tens per day

globally.

Summed TGF spectrum extending up to ~20 MeV; GLAST observations of Earth’s

atmosphere?