Post on 02-Jan-2016
RBSP SWG Meeting 1 3/5/2009
BARREL Update(Balloon Array for RBSP Relativistic Electron Losses)
R. M. Millan
and the
BARREL Team
RBSP SWG Meeting 2 3/5/2009
BARREL project overview
• Two Antarctic science campaigns during RBSP mission– 20 balloon launched each campaign in 2012 and 2013– Launched successively to set up slowly drifting array – LDB flights => ~30 day campaign duration
– >3000 hours of data in radiation belt region (L<7)– Launch sites: South African Antarctic Station (SANAE) and
Halley Bay
• Phase B test flights – Piggyback flight in December 2008– Test campaign from McMurdo in December 2009
BARREL is a multiple-balloon experiment designed to study relativistic electron precipitation.
BARREL is a multiple-balloon experiment designed to study relativistic electron precipitation.
RBSP SWG Meeting 3 3/5/2009
BARREL concept
• Launch Sites– SANAE IV– Halley Bay
BARREL uses an array of balloons to achieve its science objectives.
RBSP SWG Meeting 4 3/5/2009
Balloon observations of precipitation
• Bremsstrahlung X-rays are produced as precipitating electrons collide with atmospheric neutrals
• First observation of X-rays to MeV energies made in 1996 over Kiruna, Sweden.• Nearly stationary balloon platform => complementary to spacecraft measurements
(Foat et al., 1998)
~30 km
~70 km
RBSP SWG Meeting 5 3/5/2009
Kiruna REP Event
(from Lorentzen, 1999)
Riometer
X-ray instrument
RBSP SWG Meeting 6 3/5/2009
RBSP/Balloon Conjunctions
• Baseline: two campaigns separated by one year– Measurements of BOTH microbursts and duskside
precipitation during both camaigns.
Conjunctions with RBSP spacecraft in dusk and dawn sectors
Dusk conjunctions in 2012
Dawn conjunctions in 2013
BARREL MLT
Hou
rsH
ours
RBSP SWG Meeting 7 3/5/2009
Large-scale spatial structureS2
S3
X-ray count rate
Balloon locations
~800km separation
• Precipitation simultaneously observed by two balloons on January 21, 2005
L=3.5
L=4L=6
18MLT 6 MLT18 MLT
1840 UT
L=4L=6
18MLT 6 MLT18 MLT
1845 UT
RBSP SWG Meeting 9 3/5/2009
BARREL project overview
• Two Antarctic science campaigns during RBSP mission– 20 balloon launched each campaign in 2012 and 2013– Launched successively to set up slowly drifting array – LDB flights => ~30 day campaign duration
– >3000 hours of data in radiation belt region (L<7)– Launch sites: South African Antarctic Station (SANAE) and
Halley Bay
• Phase B test flights – Piggyback flight in December 2008– Test campaign from McMurdo in December 2009
RBSP SWG Meeting 10 3/5/2009
2009 Piggyback Test Flight
RBSP SWG Meeting 11 3/5/2009
2008/2009 Piggyback Test Flight
Launch: McMurdo, Dec. 28, 2008Duration: 54 daysAltitude: 34 km (112 kft)
Photo Courtesy D. GregoryNASA BPO
RBSP SWG Meeting 12 3/5/2009
Summary Plot: X-ray Count Rate
RBSP SWG Meeting 13 3/5/2009
Summary Plot: X-ray Count Rate
Relativistic PrecipitationRelativistic Precipitation
RBSP SWG Meeting 14 3/5/2009
~10-100 keV Precipitation Event
X-ray Count Rate
9:00 UT9:00 UT
RBSP SWG Meeting 15 3/5/2009
BARREL LocationBARREL Location
THEMIS spacecraft at 9:00 UT
TIPSOD
RBSP SWG Meeting 16 3/5/2009
THEMIS AE IndexTHEMIS AE Index
SST electronsSST electrons
Electric FieldElectric Field
THEMIS Data on Jan. 3, 2009
RBSP SWG Meeting 17 3/5/2009
Feb 14-15, 2009
X-ray SpectrumX-ray Spectrum
Cou
nts/
sC
ount
s/s
Energy (keV)Energy (keV)
RBSP SWG Meeting 18 3/5/2009
WHAT’S NEXT?
• Two Antarctic science campaigns during RBSP mission– 20 balloon launched each campaign in 2012 and 2013– Launched successively to set up slowly drifting array – LDB flights => ~30 day campaign duration
– >3000 hours of data in radiation belt region (L<7)– Launch sites: South African Antarctic Station (SANAE) and
Halley Bay
• Phase B test flights – Piggyback flight in December 2008– Test campaign from McMurdo in December 2009
RBSP SWG Meeting 19 3/5/2009
2009/2010 Test Campaign
• Currently building hardware for 6 payloads. • Integration at Dartmouth starts at end of this month• Thermal Vac and test launch in Palestine, TX summer 2009• Deploy to Antarctica November 2009
RBSP SWG Meeting 20 3/5/2009
Objectives of BARREL with RBSP
• Directly test models of wave-particle interactions.– Conjunctions between balloons and RBSP spacecraft
=> measurements of parameters needed to model interaction
– Comparison of predicted and observed precipitating flux and energy distribution
• Large-scale spatial structure and total loss rate estimates.– What are the most useful data products or methods
for displaying data?
RBSP SWG Meeting 21 3/5/2009
Cold plasma 50 cm-3, 1 eV
Magnetic Field 170 nT
Composition 85% H, 10% He, 5% O
Hot Protons:
Density -----
Energy -----
Tperp/T// ----
1 cm-3
12 keV
1.47
•Input parameters for WHAMP during the Jan. 19, 2000 precipitation event. Parameters are mean values taken from LANL MPA, except magnetic field taken from IGRF and plasma composition which was taken from Meredith et al., (2003).
•WHAMP calculation of the wave frequency for three branches of EMIC waves
ω/o
meg
ai
k k
ωim
agin
ary /
omeg
ai
Modeling EMIC Wave Growth
RBSP SWG Meeting 22 3/5/2009
Barrel Primary Science Teams
University of WashingtonNaI ScintillatorFlight Computer
UC Berkeley-SSLPower SystemMission AssuranceSE oversight
GSFC + Balloon Program OfficeProgrammatic, Management oversight
CSBFMIPLaunch Training
UC Santa CruzMagnetometerGround Station
Dartmouth CollegePI-InstitutionSystems EngineeringEngineering DataIntegration & Test
RBSP SWG Meeting 23 3/5/2009