Zobrazeno 1 - 10
of 242
pro vyhledávání: '"Yasunobu Ogawa"'
Autor:
Tikemani Bag, Yasunobu Ogawa
Publikováno v:
Scientific Reports, Vol 14, Iss 1, Pp 1-13 (2024)
Abstract Nitric oxide (NO) emission via 5.3 µm wavelength plays dominant role in regulating the thermospheric temperature due to thermostat nature. The response of NO 5.3 mm emission to the negative pressure impulse during November 06–09, 2010 is
Externí odkaz:
https://doaj.org/article/ec1ecdb06b664328a8d668a6c1d39cf4
Autor:
Takanori Nishiyama, Masato Kagitani, Senri Furutachi, Yuki Iwasa, Yasunobu Ogawa, Takuo T. Tsuda, Peter Dalin, Fuminori Tsuchiya, Satonori Nozawa, Fred Sigernes
Publikováno v:
Earth, Planets and Space, Vol 76, Iss 1, Pp 1-9 (2024)
Abstract This study presents a first simultaneous observation of $$\mathrm {N_{2}^{+}}$$ N 2 + Meinel (0,0) band (hereafter, $$\mathrm {N_{2}^{+}}$$ N 2 + (M)) aurora by cutting-edge short-wavelength infrared imaging spectrograph (NIRAS-2) and monoch
Externí odkaz:
https://doaj.org/article/2dd7d8c20b0d4324893da652d3f506fb
Publikováno v:
Earth, Planets and Space, Vol 75, Iss 1, Pp 1-11 (2023)
Abstract We study the effect of the mirror force on the collision rate due to the energetic electron precipitation into the ionosphere. We solve the motion of individual precipitating electrons with the mirror force, where collisions with neutral gas
Externí odkaz:
https://doaj.org/article/3b5fade8fac742ad81b6cc56e099b24a
Autor:
Shin-ichiro Oyama, Anita Aikio, Takeshi Sakanoi, Keisuke Hosokawa, Heikki Vanhamäki, Lei Cai, Ilkka Virtanen, Marcus Pedersen, Kazuo Shiokawa, Atsuki Shinbori, Nozomu Nishitani, Yasunobu Ogawa
Publikováno v:
Earth, Planets and Space, Vol 75, Iss 1, Pp 1-13 (2023)
Abstract Ion drag associated with the ionospheric plasma convection plays an important role in the high-latitude thermospheric dynamics, yet changes in the thermospheric wind with geomagnetic activity are not fully understood. We performed a statisti
Externí odkaz:
https://doaj.org/article/12474185579b450188a60e5cd3dcdc32
Autor:
Shin-ichiro Oyama, Heikki Vanhamäki, Lei Cai, Anita Aikio, Michael Rietveld, Yasunobu Ogawa, Tero Raita, Mirjam Kellinsalmi, Kirsti Kauristie, Boris Kozelov, Atsuki Shinbori, Kazuo Shiokawa, Takuo T. Tsuda, Takeshi Sakanoi
Publikováno v:
Earth, Planets and Space, Vol 74, Iss 1, Pp 1-17 (2022)
Abstract The thermospheric wind response to a sudden westward turning of the ion velocity at a high latitude was studied by analyzing data obtained with a Fabry–Perot interferometer (FPI; 630 nm), Dynasonde, and Swarm A & C satellites during a conj
Externí odkaz:
https://doaj.org/article/f1c0d9a93a554d81ae5f7ef5e41bf4bf
Autor:
Vladimir Safargaleev, Tima Sergienko, Keisuke Hosokawa, Shin-ichiro Oyama, Yasunobu Ogawa, Yoshizumi Miyoshi, Satoshi Kurita, Ryochi Fujii
Publikováno v:
Earth, Planets and Space, Vol 74, Iss 1, Pp 1-12 (2022)
Abstract Data from three all-sky cameras in Kiruna and Tjautjas (Sweden) were used to estimate the altitude of pulsating arc-like forms using optical tomography. The event under consideration occurred during the substorm recovery phase and comprised
Externí odkaz:
https://doaj.org/article/5a01860ee85e42b0ac96394a317600b4
Publikováno v:
Atmosphere, Vol 14, Iss 3, p 556 (2023)
The geomagnetic storm is the manifestation of the solar wind–magnetosphere interaction. It deposits huge amount of the solar energy into the magnetosphere–ionosphere–thermosphere (MIT) system. This energy creates global perturbations in the che
Externí odkaz:
https://doaj.org/article/45941bae59f449c19b0dab7966c3c078
Autor:
Takanori Nishiyama, Makoto Taguchi, Hidehiko Suzuki, Peter Dalin, Yasunobu Ogawa, Urban Brändström, Takeshi Sakanoi
Publikováno v:
Earth, Planets and Space, Vol 73, Iss 1, Pp 1-12 (2021)
Abstract We have carried out ground-based NIRAS (Near-InfraRed Aurora and airglow Spectrograph) observations at Syowa station, Antarctic ( $$69.0^{\circ }\text {S}$$ 69 . 0 ∘ S , $$39.6^{\circ }\text {E}$$ 39 . 6 ∘ E ) and Kiruna ( $$67.8^{\circ
Externí odkaz:
https://doaj.org/article/ee2690c688ff4c12a700f033f34c4393
Autor:
Yuki Kawamura, Keisuke Hosokawa, Satonori Nozawa, Yasunobu Ogawa, Tetsuya Kawabata, Shin-Ichiro Oyama, Yoshizumi Miyoshi, Satoshi Kurita, Ryoichi Fujii
Publikováno v:
Earth, Planets and Space, Vol 72, Iss 1, Pp 1-9 (2020)
Abstract Using a ground-based five-wavelength photometer, which has been operative in Tromsø, Norway since February 2017, we have statistically analyzed the lifetime of O(1S) to reveal the emission altitude of pulsating aurora (PsA). For the statist
Externí odkaz:
https://doaj.org/article/f9356eb9ae1d46f69d22d578bb9a846c
Autor:
Keisuke Hosokawa, Kohei Takami, Susumu Saito, Yasunobu Ogawa, Yuichi Otsuka, Kazuo Shiokawa, Chia-Hung Chen, Chien-Hung Lin
Publikováno v:
Earth, Planets and Space, Vol 72, Iss 1, Pp 1-11 (2020)
Abstract Here, we introduce a low-cost airglow imaging system developed for observing plasma bubble signatures in 630.0-nm airglow emission from the F region of the ionosphere. The system is composed of a small camera, optical filter, and fish-eye le
Externí odkaz:
https://doaj.org/article/1f63e17c9b034c7694cfd3b33e4c7d9c