Diffuse AuroraDiffuse Aurora
Eric Donovan – Midway Utah – June 21, 2007
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1. Introduction2. Where do the particles come from?3. How do they become diffuse auroray ff4. Remote sensing the magnetosphere5. Unstructured quiet time H+ aurora6. Structure in the diffuse aurora7. Opportunities for future studies8. Final thoughts
Acknowledgements: Stephen Mende, Fokke Creutzberg, Leroy Cogger, Brian Jackel, Emma Spanswick, Vassilis Angelopoulos, Louni Jussila, Mikko Syrjäsuo, Noora Partmies, Chuck Carlson, Howard Singer, Trond Trondsen, Mike Henderson Sandy Murphree Don Wallis Matthieu Meurant NASA
Eric Donovan June 2007
Mike Henderson, Sandy Murphree, Don Wallis, Matthieu Meurant, NASA, CSA, CDAWeb, SSCWeb.
Diffuse Aurora
A Few Details
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007Images from rom http://spaceweb.oulu.fi/~jussila/aurora/
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
I t d tiIntroduction
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
from - www.aldebaran.cz/actions/2002_aurora/start.html
Diffuse Aurora
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Diffuse Aurora
Show SNKQ Movie
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
0.2
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ergy
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FAST Orbit 05849 - 980213IES and EES data from CDAWeb
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Magnetic Latitude (Degrees)
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Magnetic Latitude (Degrees)
Diffuse Aurora
Where do the Particles Come From?From?
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
vD =ExBB2 +
m2q
2v ||2 + v⊥
2( )Bx∇BB3
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurorarg
y (k
eV)
Ene
r
Eric Donovan June 2007
Diffuse Aurorarg
y (k
eV)
Ene
r
Eric Donovan June 2007
Diffuse Aurora
How does this become Diffuse Aurora?Aurora?
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
0.2
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ergy
Flu
x
sec/
cm^2
)
FAST Orbit 05849 - 980213IES and EES data from CDAWeb
0.0
0.1
Ene
(erg
/s
1.2e6
gy F
lux
m^2
/s/s
r/eV
)
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egre
es)
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-50 -40 -30 -20 -10 0 10 radial distance (Re)
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Eric Donovan June 2007
Magnetic Latitude (Degrees)
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Eric Donovan June 2007
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Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Remote Sensing the MagnetosphereMagnetosphere
Eric Donovan June 2007
Diffuse Aurora
Latitude of equatorward boundary of proton aurora is highly correlated with magnetic field topology near the CPS inner edge.e d topo ogy ea t e C S e edge.
Eric Donovan June 2007
Diffuse Aurora
T
chu
esk
0240
0245
0250
0255
0300
0305
0310
0315
0320
The brightness of the proton aurora tracks sudden changes in solar wind dynamic pressure.
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gil
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32
47
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(R
)
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rees
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62
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ss (
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UT (hh )
-10010
SY
M-H
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UT (hhmm)
Diffuse Aurora
Poleward boundary of the diffuse 630 nm (Oxygen “Redline”) emissions is an excellent proxy for the open-closed boundary.
Eric Donovan June 2007
Diffuse Aurora
Unstructured Quiet Time H+ AuroraAurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Structure in the Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Proton (Hβ) auroral fading before EVERY substorm onsetonset.
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse AuroraQuestions that need answering!
Frames separated by 3 seconds
Vertical striations on keograms are a consequence of patches “flashing” on.
Whatever process is on one level aliasing with 3 seconds & the one second exposure time.
Eric Donovan June 2007
094533 094536 094539Athabasca THEMIS ASI 2007-03-13
Diffuse Aurora
Ath bAthabasca
Optical Pi2
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p
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Reproduced from Figure 10 in Yamamoto, T., S. Inoue, and C. Meng, Formation of auroral omega bands in the paired region 1 and region 2 field aligned current system JGR 102(2531 2544) 1997
Eric Donovan June 2007
the paired region 1 and region 2 field-aligned current system, JGR, 102(2531-2544), 1997.
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Opportunities for New Studies
Eric Donovan June 2007
Diffuse AuroraQuestions that need answering!
Why does proton auroral fading occur in the 20 minutes prior to onset?Is proton diffuse auroral precipitation structured?Wh t th l ti t ib ti f th i f t i it ti ?
Proton Diffuse Aurora
What are the relative contributions of the various causes of proton precipitation?Are inductive electric fields important in proton auroral precipitation near onset?Are all discrete electron auroral arcs embedded in the proton aurora?Is there such a thing as a discrete proton auroral arc?g p
What determines structure in the electron diffuse aurora?What is the role of CPS turbulence in diffuse auroral structure/brightness?
Electron Diffuse Aurora
What is the role of CPS turbulence in diffuse auroral structure/brightness?Develop a relationship between CPS conditions and electron auroral brightness.Do processes such as BBFs play a role in diffuse auroral brightness?Is there a diffuse auroral signature of mid-tail reconnection?Develop a relationship between CPS conditions and electron auroral brightness.What are the relative contributions of the various causes of electron precipitation?Why is the poleward boundary of the diffuse electron aurora sometimes so sharp?Is the redline poleward boundary always a good proxy for the separatrix?
Eric Donovan June 2007
Is the redline poleward boundary always a good proxy for the separatrix?
Diffuse AuroraQuestions that need answering!
Eric Donovan June 2007
094533 094536 094539
Diffuse AuroraQuestions that need answering!
Frames separated by 3 seconds
Vertical striations on keograms are a consequence of patches “flashing” on.
Whatever process is on one level aliasing with 3 seconds & the one second exposure time.
Show THEMIS-Athabasca Movie
Eric Donovan June 2007
094533 094536 094539Athabasca THEMIS ASI 2007-03-13
Diffuse AuroraPlasma physical mechanisms of DA precipitation
Athabasca University Geophysical ObservatoryInstrument Complement
NORSTAR H-beta ImagerOMTI Multi-Spectral ImagerNORSTAR Rainbow ImagerNORSTAR D A I (N FNORSTAR Denswe Array Imager (Narrow FTHEMIS Panchromatic ImagerOMTI Meridian Scanning PhotometerOMTI Induction Coil MagnetometerNRCAN Fluxgate (at Meanook)NRCAN Riometer (at Meanook)NORSTAR Dense Array Imager (at Legal)
Fl M
MSP Scan Plane
Fluxgate Mags
MAGICMACCSDMIAGIAthabasca U.IGPP-LANLMcMac
61.37
62.37
63.37
Athabasca
Slave Lake
Legal
Calling Lake
THEMIS GBOTHEMIS EPOMEASURENRCanCARISMA
CGSM/NORSTAR ContextProposed AUGO Campaign
Edmonton
Red Deer
Calgary
Legal
Eric Donovan June 2007
Eric Donovan & Mike GreffenCGSM/NORSTAR Context
Meanook (very near Athabasca in above map)
Diffuse Aurora
CHAMP OrbitMagnetic Midnight
In the following plots I am stepping forward one orbit at a timeIn the following plots I am stepping forward one orbit at a time starting from an orbit where the satellite passes through the night side over eastern Russia.
The contours show constant PACE latitudes from 50 to 80 degrees gand longitudes separated by one hour of local time.
The orbit is shown in red (projected geographically to the surface which is not too bad for the orbit we are talking about. Magnetic
Eric Donovan June 2007
g gmidnight is indicated by the dashed white thick line from 50 to 80 degrees PACE.
The black dots indicate fluxgate mags in North America and
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Eric Donovan June 2007
Diffuse Aurora
Considering just this one day in 2002, had all of the ASIs been operating that I expect will be operating by 2009 been running….
Champ would have passed though the FOVs of roughly 50 ASIs with one pass having continuous optical coverage from 55 degrees mlat (NORSTAR) to the magnetic pole (CHAIN) and passing though the FOVs of AMISR and PolarDARN.
WE can expect this number of conjunctions for all three SWARM satellites during most times of year. With three satellites and the quality f E d B b i h SWARM ill id hi ill b
Eric Donovan June 2007
of E and B observations that SWARM will provide this will be an unprecedented opportunity for studies of auroral eledctrodynamics.
Diffuse Aurora
Final Thoughts
Eric Donovan June 2007
Diffuse Aurora
Plasma Physics
What causes the
Geospace Remote Sensing
Role in Dynamics
Is the diffuse auroraWhat causes the precipitation?? What can we infer
about geospace from the diffuse aurora?
Is the diffuse aurora “important”?
ECHChorusEMIC
OC BoundaryE- CPS inner edgeH+ CPS inner edge
Loss of low E e-Loss of high E e-Loss of low E H+EMIC
TurbulencePotential DifferenceFL Curvature
H+ CPS inner edgeStretched-dipolar transStretchingH+ pressure
f
Loss of low E H+Low of high E H+Direct role in currentsConductivity effects
MASER●●
Presence of MHD wavesPresence of waves
●●
Role in wave generation●●
Eric Donovan June 2007
Diffuse Aurora
References
Eric Donovan June 2007
Diffuse AuroraHigh Points
Rees, M., A. Belon, and G. Romick,The systematic behvior of H emission in the aurora, PSS, 5, 87-91, 1961.
Discovery & Early Exploration of the Diffuse Aurora
Petschek., H., and C. Kennel,Tail flow, auroral precipitation, and ring currents., Trans. Am. Geophys. Union, Volume 47, 137-138, 1966.
L i A P P l S I Ak f d C ALui, A., P. Perreault, S.-I. Akasofu, and C. AngerThe Diffuse Aurora, PSS, Volume 21, 857-861, 1973
Eather, R., and S. MendeAirborne Observations of Auroral Precipitation PatternsAirborne Observations of Auroral Precipitation Patterns,JGR, Volume 76, 1746-1755, 1971.
Fukunishi,H.,Dynamic relationship between proton and electron auroral substormsDynamic relationship between proton and electron auroral substorms,JGR, Volume 80, 553-574, 1975.
Mende, S., and R. Eather, Monochromatic all-sky observations and auroral precipitation patterns,
Eric Donovan June 2007
y p p pJGR, Volume 81., 3771-138, 1966.
Diffuse AuroraHigh Points
Frank, L., Relationship of the plasma sheet, ring current, trapping boundary, and plasmapause near the magnetic equator and local midnight, JGR, 76(2265 2275) 1971
Properties of the major relevant plasma populations (mostly the CPS)
76(2265-2275), 1971.
Wing, S., Central plasma sheet ion properties as inferred from ionospheric observations, JGR, 103(6785-6800), 1998.
Friedel, R.,Airborne Observations of Auroral Precipitation Patterns,JGR, 76(1746-1755), 1971.
Kennel, C., and H. Petchek, Limit on stably trapped particle fluxes, JGR, 71(1-28), 1966.
Diffusion mechanisms
Sergeev, V., E. Sazhina, N. Tsyganenko, J. Lundblad, and F. Søraas, Pitch-angle scattering of energetic protons in the magnetotail current sheet as the dominant source of their isotropic precipitation into the nightside i h PSS 31(1147 1155) 1983
Eric Donovan June 2007
ionosphere, PSS, 31(1147-1155), 1983.
Diffuse AuroraHigh Points
A. Lui, C.-I. Meng, and S. Ismail, Large amplitude undulations on the equatorward boundary of the diffuse aurora, JGR, 87(2385-2400), 1982.
Inferring things from diffuse auroral boundaries
W. Imhof, Fine resolution measurements of the L-ependent energy threshold for isotropy at the trapping boundary, JGR, 93(9743-), 1988.
V. Sergeev and B. Gvozdevsky, MT-index: a new index to characterize the configuration of the magnetotail, Ann. Geophys., 13(1093-1103), 1993.
G. Blanchard, L. Lyons, J. Samson, and F. Rich, Locating the polar cap boundary from observations of 6300 Å auroral emission, JGR, 100(7855-7862), 1995.
E. Donovan, B. Jackel, I. Voronkov, T. Sorirelis, F. Creutzberg, and N. Nicholson,Ground-based optical determination of the b2i boundary: A basis for an optical MT-index, JGR, 108(doi:10.1029/2001JA009198), 2003.
Rae, Kabin, Rankin, Fenrich, Liu, Wanliss, Ridley, Gombosi, and De ZeeuwComparison of photometer anf glbal MHD determination of the open-closed field line boundary, JGR, 109(doi:10.1029/2003JA009968), 2004.
Eric Donovan June 2007
Diffuse AuroraHigh Points
M. Ashour-Abdalla, and C. Kennel,Diffuse auroral precipitation, in Auroral Processes, C. Russell Ed., 1977.
Papers from which I learned the most
V. Sergeev, E. Sazhina, N. Tsyganenko, J. Lundblad, and F. Søraas,Pitch-angle scattering of energetic protons in the magnetotail currentsheet as the dominant source of their isotropic precipitation into the nightime ionosphere PSS 31(1147 1155) 1983nightime ionosphere, PSS, 31(1147-1155), 1983.
D. Fontaine and M. BlancA theoretical approach to the morphology and dynamics of diffuse auroral zones, JGR, 88(7171-7184), 1983.zones, JGR, 88(7171 7184), 1983.
D. Fairfield and A. ViñasThe inner edge of the PS and the diffuse aurora, JGR, 89(841-854), 1984.
P N ll Y F ld t i Y G l i d C I MP. Newell, Y. Feldstein, Y. Galperin, and C.-I. Meng,Morphology of nightside precipitation, JGR, 101(10737-10748), 1986.
Frey, Mende, Carlson, Gérard, Hubert, Spann, Gladstone, and ImmelThe electron and proton aurora as seen by IMAGE FUV and FAST GRL
Eric Donovan June 2007
The electron and proton aurora as seen by IMAGE-FUV and FAST, GRL, 28(1135-1138), 2001.