(Proposal ID) S14B-055

(PI) Kasaba Yasumasa

(Proposal Title)
 Horizontal and vertical structures of Jovian IR aurora with EUV/UV (retry)

(Abstract)
We propose the IRCS observation of Jupiter's IR aurora, which consists of H_2 
(neutral) and H_3^+ (plasma) emissions, in Jan 2015 as the retry of S14A-061 
suffered by bad weather. IRCS can provide simultaneous slit spectroscopy of 
multiple H_2 and H_3^+ emission lines in K-band with H_3^+ line images in L-
band, with the highest spatial resolution (0.1" = 200km at Jupiter) assisted 
by AO188 locked to Galilean satellites. This strong capability provides the 
best chance to compare neutral (H_2) and plasma (H_3^+) atmospheres in both 
hemispheres, and to solve the contradicted differences in the horizontal and 
vertical distributions of neutral (H_2) and plasma (H_3^+) aurora found in our 
past studies. Tis proposal is jointed to JAXA Hisaki/EXCEED, which is 
providing  the first continuous information of aurora activity in UV and Io 
plasma torus in EUV. With Hisaki, we will be able to study the contribution 
from the flux and energy of precipitating aurora electrons derived from UV and 
the mass loading from Io plasma torus derived from EUV. The results will 
contribute to the study of the heating and cooling of Jovian thermosphere, 
which is the key of the energy transfer through the Jovian Magnetosphere - 
Ionosphere - Thermosphere coupling system.