11:00 〜 13:00
[PCG19-P06] 低エネルギー電子を用いたフローティング式アバランシェフォトダイオード実験
Avalanche PhotoDiodes (APDs) are prevailing for high-energy electron detection with rough energy analyses in space observations. For instance, the electron detector system of the Medium-Energy Particle instrument for electrons (MEP-e) for ERG mission consists of an array of APDs [Kasahara et al., EPS 2018]. Kasahara et al. [NIM, 2012] reported that a minimum detectable energy with an APD is 5 keV at 20 ℃.
Our purpose is to reduce the lowermost energy of electron energy analyses with APD and to install APDs in low-energy electron analyzers. In order to detect lower-energy electrons below 5 keV, we applied the floating voltage to APD so that the incident electrons could be accelerated up to energies enough large for the APD detection, depending on the floating voltage.
While we could analyze 5 keV electrons by about 4 keV energy-resolution without the floating voltage at 20 ℃ in our beam line facility, we also confirmed an equivalent energy-resolution due to using the low-pass filtered floating voltage when electrons are accelerated by 5 keV.
We installed electron guns near APD so that lower-energy electrons irradiated it under Earth’s magnetic field. Then, we will be able to detect electrons of a few hundreds of eV by applying floating voltage. This shows the possibility that the floating-mode APDs could be applied as low-energy electron detectors with a high-sensitivity and a rough energy analysis.
Our purpose is to reduce the lowermost energy of electron energy analyses with APD and to install APDs in low-energy electron analyzers. In order to detect lower-energy electrons below 5 keV, we applied the floating voltage to APD so that the incident electrons could be accelerated up to energies enough large for the APD detection, depending on the floating voltage.
While we could analyze 5 keV electrons by about 4 keV energy-resolution without the floating voltage at 20 ℃ in our beam line facility, we also confirmed an equivalent energy-resolution due to using the low-pass filtered floating voltage when electrons are accelerated by 5 keV.
We installed electron guns near APD so that lower-energy electrons irradiated it under Earth’s magnetic field. Then, we will be able to detect electrons of a few hundreds of eV by applying floating voltage. This shows the possibility that the floating-mode APDs could be applied as low-energy electron detectors with a high-sensitivity and a rough energy analysis.