[P-EM11] Dynamics of the Inner Magnetospheric System

[PEM11-P02] LAMPロケット搭載多波長オーロラ観測カメラAIC2による脈動オーロラ観測の初期報告

*坂野井 健¹、川村 美季¹、浅村 和史²、三好 由純³、細川 敬祐⁴、Halford Alexa⁵、Lessard Marc⁶ (1.東北大学大学院理学研究科惑星プラズマ・大気研究センター、2.JAXA宇宙科学研究所、3.名古屋大学宇宙地球環境研究所、4.電気通信大学情報理工学研究科、5.NASAゴダード宇宙飛行センター、6.ニューハンプシャー大学)

キーワード：脈動オーロラ、ロケット、マイクロバースト

We report the initial results of pulsating aurora observation with a multi-spectral auroral camera AIC2 on the LAMP The purpose of the LAMP rocket is to clarify the relationship between pulsating aurora and microbursts with simultaneous particle, magnetic field, and and imaging measurements. The instrumental package called PARM2 (Pulsating AuRora and Microburst 2) is provided by a Japanese team. AIC2 is one of PARM2 which will perform auroral imaging at two wavelengths simultaneously. AIC2 consists of 2 CMOS cameras, AIC-S1 and AIC-S2, and electronics AIC-E. AIC2 is characterized by a low noise (1.6 e-RMS) and wide dynamic range sampling capability (16 bit A/D) using the consumer CMOS sensor (ZWO AS1183MM). AIC-S1 targets the auroral molecular nitrogen emission at 670 nm (FWHM 20 nm) in the E-region with a field of view of 29 deg x 29 deg which covers 170 km x 170 km with a resolution of 3 km x 3 km at apogee (~440 km altitude). Combining the despun platform (provided by University of New Hampshire) with rocket attitude control, AIC-S1 continuously points to the magnetic footprint of rocket to carry out simultaneous observation between fine structure of pulsating aurora and precipitating electrons. AIC-S2 observes the auroral atomic oxygen emission at 844.6 nm (FWHM 4.4 nm) in the F-region with a φ106 deg circle field-of-view to observe the thickness of aurora and auroral distribution in the wide range. Two cameras take images simultaneously with a time resolution of 10 frame/s. The dynamic ranges of AIC-S1 and S2 are 1.1 - 860 kR, and 0.4 - 5800 kR, respectively, with a typical sensitivity resolution of a few tens Rayleighs. AIC-E consists of two NanoPi M4V2 board computers, FPGAs, power supply, and signal processing electronics to handle a large amount of image data generated in two cameras. We also use a newly developed oscillating heat pipes to cool the two CPUs of NanoPi boards. Total weight and power of AIC2 are 3.0 kg and 20 W, respectively.
From August to November 2021, the performance of AIC2 was verified by the integrated electrical interface test with the common electronics (COM-E) and other PARM2 instruments (high-energy electron sensor HEP and magnetometer MIM). We also carried the environmental tests of AIC2 including vibration, vacuum, and thermal tests, and focus alignment check. From December 2021 to January 2022, the PARM2 instruments (AIC2, high-energy electron sensor HEP and magnetometer MIM, and COM-E) were tested at Wallops Flight Facility of NASA and verified their functions. Flight operation is scheduled at Poker Flat, Alaska, from the middle of February to the beginning of March 2022. Ground observation with high-speed Phantom and EMCCD cameras are planned at Poker Flat, Venetie and Fort Yukon to observe internal 3-Hz modulation of pulsating aurora. Coordinate LAMP rocket and ground observations of pulsating aurora bring us the precise relationship between pulsating auroral emission and microburst, and understanding their generation mechanisms.