Presentation on theme: "Density and payload potential HM, Erpa, PFISR, waves."— Presentation transcript:
Density and payload potential HM, Erpa, PFISR, waves
Density from HF?
First try inconsistent
Consider rammed thermal ions But analysis assumes O+ only
How about the e- erpa? Its skin channel is a langmuir probe with V_b=+4V But it doesn’t know about phi-s/c; also, no absolute scale
Certainly a density “hole” where precip is; but should there be?
Velocity fields as aurora alarm
Density from LHR?
Gives few-15*10^3/cc if O+ What if NO+?
ERPA stuff Electron RPA with +4V front screen Skin channel = Erpa-peak => energy of peak response Erpa-hi = electrons greater than 3eV (non- thermal) Temp: phi_sc = 5kT+Vsphere-skin (sphere float plus differential charging to skin)
Comparisons of phi-sc Dots: HM peak –Eram Black lines: 5kTe + avg(Vss) sub and fwd, no tweaks Blue lines: aft-erpa-peak fwd-erpa-peak – 0.42 HM cutoff ~1eV ERPA cutoff ~0.8eV Truest: 5kTe+avg(Vss)
Correcting erpa-peak Upper black: truest Bottom black: aftpeak Blue: Aftpeak + afthi*200 True from Te and HM consistent Erpapeaks have payload- dependent DC offset Erpapeaks suppressed by higher energy e- flux