[P-EM13] Dynamics of the Inner Magnetospheric System

[PEM13-P29] LAMP Observation of Precipitating Electron Simultaneously Forming Microbursts and Pulsating Auroras

*Taku Namekawa^1,2, Takefumi Mitani², Kazushi Asamura², Yoshizumi Miyoshi³, Keisuke Hosokawa⁴, Marc Lessard⁵, Chrystal Moser⁵, Alexa J. Halford⁶, Takeshi Sakanoi⁷, Miki Kawamura⁷, Masahito Nose³, Reiko Nomura², Mariko Teramoto⁸, Don Hampton⁹, Mykhaylo Shumko¹⁰, Allison N. Jaynes¹¹, Matthew G. McHarg¹², Vincent Ledvina⁹ (1.The University of Tokyo, 2.The Japan Aerospace Exploration Agency, 3.Nagoya University, 4.The University of Electro-Communications, 5.University of New Hampshire, 6.NASA Goddard Space Flight Center, 7.Tohoku University, 8.Kyushu Institute of Technology, 9.University of Alaska Fairbanks, 10.University of Maryland, 11.University of Iowa, 12.United States Air Force Academy)

Keywords:microburst, pulsating aurora, sounding rocket

Microburst precipitations of several hundred keV to several MeV electrons are observed as precipitations into the Earth’s auroral atmosphere on a time scale of less than one second. It is suggested that microbursts are a loss mechanism of the outer radiation belt electrons [e.g., Thorne et al., 2005; Clilverd et al., 2006; Dietrich et al., 2010; Lorentzen et al., 2001]. Although microbursts are suggested to be caused by pitch angle scattering due to magnetospheric whistler-mode chorus waves propagating from the magnetic equatorial plane to higher magnetic latitudes, observational verification has not been made yet [Miyoshi et al., 2020]. The mechanism of microbursts under consideration is similar to that of pulsating aurora observed in the Earth’s polar region. Thus, the origin of microbursts can be clarified by simultaneous observation of microbursts and pulsating auroras.
A high energy electron detector (HEP) was developed and installed in Loss through Auroral Microburst Pulsation (LAMP) sounding rocket experiment which aimed to simultaneously observe pulsating auroras and microbursts. LAMP launched at 11:27:30 UT (MLT = 0.1h) on March 5, 2022 and simultaneously observed pulsating auroras and quasi-relativistic electron microbursts with inverse energy dispersion where the high energy electrons appear after the low energy electrons. The observed inverse energy dispersion is consistent with the theoretical expectation [Miyoshi et al., 2020]. In this presentation, we will show the outline of HEP and the observational results of LAMP experiment.