Premium
Photometric measurement of cold helium ions in the magnetotail by an EUV Scanner onboard planet‐B: Evidence of the existence of cold plasmas in the near‐Earth plasma sheet
Author(s) -
Yoshikawa I.,
Yamazaki A.,
Shiomi K.,
Yamashita K.,
Takizawa Y.,
Nakamura M.
Publication year - 2000
Publication title -
geophysical research letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.007
H-Index - 273
eISSN - 1944-8007
pISSN - 0094-8276
DOI - 10.1029/2000gl000100
Subject(s) - plasma sheet , plasma , magnetosphere , physics , ion , extreme ultraviolet lithography , helium , extreme ultraviolet , planet , astronomy , astrophysics , atomic physics , optics , nuclear physics , laser , quantum mechanics
The first optical measurement of He + ions in the plasma sheet was successful by using the XUV scanner onboard Planet‐B. The intensity of He II (304 Å) was ∼0.02 Rayleigh. This result encourages future imaging missions for the whole magnetosphere by detecting He II (304 Å) emission. This is also a proof of the existence of cold plasmas in the plasma sheet. The existence of cold ions brings a new question: How can they remain cold in the plasma sheet?