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I nter P lanetary S cintillation IPS. induced Pluripotent Stem cell i PS. What is the I nter P lanetary S cintillation (IPS)?. Why is the IPS a useful and powerful tool for space weather forecast?. I nter p lanetary S cintillation. V & △Ne. 1964
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InterPlanetaryScintillationIPS induced Pluripotent Stem cell iPS
What is the InterPlanetary Scintillation (IPS)? Why is the IPS a useful and powerful tool for space weather forecast?
Interplanetary Scintillation V & △Ne
1964 Discoveryof interplanetary scintillation Antony Hewish
Large aperture (high gain) antenna • Short-time constant receiver 81.5 MHz 36000 m2
5 years later after IPS discovery IPS observations were begun in Japan.
STEL Radiotelescope Array dedicated for IPS Observations Sugadaira Kiso • Data • Solar Wind Speed • Scintillation level (g-value) Aperture Size = ~ 2000or ~ 3400㎡ Frequency 327MHz Toyokawa Fuji
STEL IPS Antennas as Viewed in Google Earth Fuji IPS Telescope (FIT) Kiso IPS Telescope (KIT)
Toyokawa Observatory SWIFT
Solar Wind Imaging Facility at Toyokawa 327 MHz EW40m×NS106m
Fresnel filter a weight z E Radio source
Radio source size a weight z Radio source E
Solar wind electron distribution Sun ★ weight E Radio source E
less weighted by radio source size effect and lower SW density Line of sight Highest SW density less weighted by Fresnel filter and lower SW density
Fresnel filter zo=2πa2/λ Radio source a/zo>θ zo=1 AU =1.5×108 km λ=1 m ⇒ a=150 km θ<0.2 arcsec
IPS vs. in situ after Coles (1978)
Scintillation index Heliocentric Distance (Rs)
It can observe the near Sun region. Interplanetary Scintillation It can observe high latitude regions. It has wide spatial coverage of 3D space. It can observe vast space in a short time. Complementary observations to spacecraft
Ulysses First and only one Solar polar orbiter
NS asymmetry Velocity gradient bimodal
V B Plasma density distribution, IPS diffraction pattern