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High Energy Measurements for Solar, Heliospheric, Magnetospheric, and Atmospheric Physics

Explore cutting-edge high-energy measurement projects in solar, atmospheric, and magnetospheric physics including RHESSI, THEMIS, and more. Discover advanced instrumentation and groundbreaking findings in this fascinating field.

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High Energy Measurements for Solar, Heliospheric, Magnetospheric, and Atmospheric Physics

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  1. High Energy Measurements for Solar, Heliospheric, Magnetospheric, and Atmospheric Physics R. P. Lin J. Sample, A. Shih, S. Christe, S. Krucker, I. Hannah Physics Department & Space Sciences Laboratory University of California, Berkeley & D. Smith (UCSC), R. Millan (Dartmouth)

  2. Apollo 15 Subsatellite

  3. FAST • (Fast Auroral SnapshoT) • Science Package • Electric Field Instruments • Particle Instruments • Electronics • Mission Operations • Science Operations • Launched on 21 Aug 1996 • Mission Presently Operating

  4. RHESSI • (Ramaty High Energy Solar Spectroscopic Imager) • Project Management • Spacecraft Bus • Science Package • Imager • Spectrometer • Electronics • Mission Operations • Science Operations • Ground Data Systems • Launched February 5, 2002 • Mission presently operating

  5. Cosmic Hot interstellar Plasma Spectrometer (CHIPS)

  6. THEMIS Integration and Test • Currently ongoing at the UCB Space Sciences Laboratory • 5 identical spacecraft & instrument suites

  7. RHESSI TGFs: Lightcurves Durations from 200 us to 3.5 ms; consistent with BATSE, shorter than most TLEs.

  8. RHESSI TGFs: Spectrum Summed spectrum of 289 TGFs Spectra tend to be similar from event to event, but slightly more variation than chance Models are relativistic runaway breakdown simulation by J. Dwyer. Unabsorbed bremsstrahlung must be steeper than E around 1 MeV; spectrum seen requires > 50 g/cm of intervening air (Dwyer & Smith 2005, in press) -1 2

  9. Jan 17 2004, 12:46:50.970 Longest and brightest RHESSI TGF Northern Chad (Sahara). No storms here, but plenty of storms in January at the conjugate point. If every TGF has a conjugate flash, the first Sahara event we see should be faint, not bright! Unless..... We got lucky and caught the e- beam directly with the spacecraft! Currently looking for conjugate storms & sferics.

  10. Multiple Scintillators for Terrestrial, Cosmic, Solar, and Magnetospheric Events (MSTCSM) John Sample and Albert Y. Shih

  11. Science objectives of MSTCSM MSTCSM can provide improved and completely new observations of events ranging from those of terrestrial or magnetospheric origins to those of solar or cosmic origins MSTCSM observes 20 keV to 16 MeV photons and 600 keV to 6 MeV electrons with excellent time resolution For terrestrial gamma-ray flashes (TGFs), MSTCSM is more sensitive than RHESSI and can obtain better timing information and structure For microbursts in the magnetosphere, MSTCSM can determine the spectrum of the relevant particles for the first time and improve the pitch angle determination by SAMPEX For solar flares, MSTCSM has an order of magnitude better time resolution than RHESSI and more effective area (~ 8 times more at X-ray energies, and ~ 2–3 times more at gamma-ray energies) For cosmic sources such as gamma-ray bursts and magnetars, MSTCSM can look for time structure better than other instruments

  12. Instrument design for MSTCSM To Sun 2 cm To Earth 20 cm 40 cm LaBr plastic To Sun 2 cm To Earth 20 cm Spacecraft in a sun-synchronous polar low-Earth orbit Fixed pointing towards the Earth and the Sun, but minimal requirements on accuracy Two lanthanum bromide (LaBr) scintillators and four plastic scintillators, each 1-cm thick Two sizes of plastic scintillators for dynamic range Orientation of scintillators is depicted for two points of view One set of scintillators is shadowed from the Sun for deadtime and pileup considerations

  13. Technical details for MSTCSM Analysis chain similar to RHESSI Each scintillator event recorded separately with time and energy Fast and slow shaping channels Timing: < 0.05 microseconds At very high count rates, individual events are not retained, but spectra are produced from the fast channel Onboard generation of lightcurves for automatic and/or manual selection of data periods to keep ~ 3 GB of data produced per day 8 GB solid state recorder 4 Mbit/s downlink ~ 0.1 m2 of solar panels with battery to provide ~ 10 W power < 0.1 m3 total volume

  14. Spectral Components total model broad De-excitation lines -narrow Neutron-capture2.2 MeV power law - electron bremsstrahlung 511 keV- positron annihilation

  15. Germanium Array in Low Earth Orbit (GALEO)

  16. Solar Hard X-ray Focusing Optics S. Christe, S. Krucker, B. Ramsay (MSFC) • Flare/CME Coronal Acceleration Region • Micro-Nano Flares • Electron beams • Type III radio bursts. • Type I Bursts • Quiet Sun • Axions

  17. Science - Quiet Sun/Nanoflares

  18. Hannah et al, 2007 THEMIS THEMIS THEMIS

  19. Optic - 1 m focal length

  20. Some Pictures Detectors : Pixelated Si

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