Publication list

 

Refereed journal

First author

​

  1. Oyama, S., Shinbori, A., Ogawa, Y., Kellinsalmi, M., Raita, T., Aikio, A., et al. (2020). An ephemeral red arc appeared at 68° MLat at a pseudo breakup during geomagnetically quiet conditions. Journal of Geophysical Research: Space Physics, 125, e2020JA028468. https://doi.org/10.1029/2020JA028468

  2. Oyama, S., T. T. Tsuda, K. Hosokawa, Y. Ogawa, Y. Miyoshi, S. Kurita, A. E. Kero, R. Fujii, Y. Tanaka, A. Mizuno, T. Kawabata, B. Gustavsson and T. Leyser, Auroral molecular-emission effects on the atomic oxygen line at 777.4 nm, Earth, Planets and Space, 70:166, doi:10.1186/s40623-018-0936-z, 2018.

  3. Oyama, S., Kubota, K., Morinaga, T., Tsuda, T. T., Kurihara, J., Larsen, M. F., M. Yamamoto, L. Cai, Simultaneous FPI and TMA measurements of the lower thermospheric wind in the vicinity of the poleward expanding aurora after substorm onset. Journal of Geophysical Research: Space Physics, 122. https://doi.org/10.1002/2017JA024613, 2017 featured in Eos Research Spotlight

  4. Oyama, S., A. Kero, C. J. Rodger, M. A. Clilverd, Y. Miyoshi, N. Partamies, E. Turunen, T. Raita, P. T. Verronen, and S. Saito, Energetic electron precipitation and auroral morphology at the substorm recovery phase, J. Geophys. Res. Space Physics, 122, doi:10.1002/2016JA023484, 2017.

  5. Oyama, S., K. Shiokawa, Y. Miyoshi, K. Hosokawa, B. J. Watkins, J. Kurihara, T. T. Tsuda, and C. T. Fallen, Lower thermospheric wind variations in auroral patches during the substorm recovery phase, J. Geophys. Res. Space Physics, 121, doi:10.1002/2015JA022129, March 31, 2016.  featured in JGR Space Physics

  6. Oyama, S., Y. Miyoshi, K. Shiokawa, J. Kurihara, T. T. Tsuda, and B. J. Watkins, Height-dependent ionospheric variations in the vicinity of nightside poleward expanding aurora after substorm onset, J. Geophys. Res. Space Physics, 119, doi:10.1002/2013JA019704, May 5, 2014.

  7. Oyama, S., T. Watanabe, R. Fujii, S. Nozawa, and T. T. Tsuda, Estimation of the layered ionospheric conductance using data from a multi-wavelength photometer at the European Incoherent Scatter (EISCAT) radar site, Antarctic Record, 57(3), 339-356, December, 2013.

  8. Oyama, S., J. Kurihara, B. J. Watkins, T. T. Tsuda, and T. Takahashi, Temporal variations of the ion-neutral collision frequency from EISCAT observations in the polar lower ionosphere during periods of geomagnetic disturbances, J. Geophys. Res., 117, A05308, doi:10.1029/2011JA017159, March 26, 2012.

  9. Oyama, S., and B. J. Watkins, Generation of atmospheric gravity waves in the polar thermosphere in response to auroral activity, Space Science Review, doi:10.1007/s11214-011-9847-z, November, 2011.

  10. Oyama, S., A. Brekke, T. T. Tsuda, J. Kurihara, and B. J. Watkins, Variance of the vertical ion speed measured with the EISCAT UHF radar in the polar lower ionosphere at Tromsoe, Norway, J. Geophys. Res., 116, A00K06, doi:10.1029/2010JA016129, April 4, 2011.

  11. Oyama, S., K. Shiokawa, J. Kurihara, T. T. Tsuda, S. Nozawa, Y. Ogawa, Y. Otsuka, and B. J. Watkins, Lower-thermospheric wind fluctuations measured with an FPI during pulsating aurora at Tromsoe, Norway, Ann. Geophysicae, 28, 1847-1857, 2010.

  12. Oyama, S., T. T. Tsuda, T. Sakanoi, Y. Obuchi, K. Asamura, M. Hirahara, A. Yamazaki, Y. Kasaba, R. Fujii, S. Nozawa, and B. J. Watkins, Spatial evolution of frictional heating and the predicted thermospheric-wind effects in the vicinity of an auroral arc measured with the Sondrestrom incoherent-scatter radar and the Reimei satellite, J. Geophys. Res., 114, A07311, doi:10.1029/2009JA014091, May 26, 2009.

  13. Oyama, S., B. J. Watkins, S. Maeda, H. Shinagawa, S. Nozawa, Y. Ogawa, A. Brekke, C. Lathuillere, and W. Kofman, Generation of the lower-thermospheric vertical wind estimated with the EISCAT KST radar at high latitudes during periods of moderate geomagnetic disturbance, Ann. Geophysicae, 26, 1491-1505, 2008.

  14. Oyama, S., B. J. Watkins, F. T. Djuth, M. J. Kosch, P. Bernhardt, and C. J. Heinselman,Persistent enhancement of the HF pump-induced plasma line measured with a UHF diagnostic radar at HAARP, J. Geophys. Res., 111, A06309, doi:10.1029/2005JA011363, March 15, 2006.

  15. Oyama, S., B. J. Watkins, S. Nozawa, S. Maeda, and M. Conde, Vertical ion motions observed with incoherent-scatter radars in the polar lower ionosphere, J. Geophys. Res., 110, A04302, doi:10.1029/2004JA010705, January 25, 2005.

  16. Oyama, S., B. J. Watkins, S. Maeda, and J. Watermann, Application of a new beam configuration to estimate lower thermospheric vertical velocities at high latitudes with mono-static incoherent scatter radars, Radio Sci., 40, RS4005, doi:10.1029/2004RS003205, April 26, 2005.

  17. Oyama, S., C. Lathuillere, S. Maeda, and B. J. Watkins, Summer-winter dependences of day-night differences in the ion temperature in the polar upper F region, Geophys. Res. Lett., 31, L05806, doi:10.1029/2003GL018820, February 9, 2004.

  18. Oyama, S., S. Nozawa, S. Maeda, Y. Murayama, R. Fujii, and H. Shinagawa, Field-aligned ion motions in the polar E-F transition region: Mean characteristics, J. Geophys. Res., 108(A8), 1334, doi:10.1029/2003JA009830, June 6, 2003.

  19. Oyama, S., M. Ishii, Y. Murayama, H. Shinagawa, S. C. Buchert, S. Nozawa, R. Fujii, and W. Kofman, Generation of atmospheric gravity waves associated with auroral activity in the polar F region, J. Geophys. Res., 106(A9), 18543–18554, doi:10.1029/2001JA900032, February 23, 2001.

  20. Oyama, S., H. Shinagawa, S. C. Buchert, R. Fujii, S. Nozawa, M. Ishii, Y. Murayama, and W. Kofman, Effects of auroral arc on the generation of atmospheric gravity waves in the auroral F-region, Advances in Space Research, 27, 1767-1772, 2001.

  21. Oyama, S., S. Nozawa, S. C. Buchert, M. Ishii, S. Watari, E. Sagawa, W. Kofman, J. Lilensten, and R. Fujii, Effects of atmospheric oscillations on the field-aligned ion motions in the polar F-region, Ann., Geophysicae, 18, 1154-1163, 2000.

 

Coauthor

  1. Kawai, K., K. Shiokawa, Y. Otsuka, S. Oyama, Y. Kasaba, Y. Kasahara, F. Tsuchiya, A. Kumamoto, S. Nakamura, A. Matsuoka, S. Imajo, Y. Kazama, Shiang-Yu, Wang, Sunny W. Y. Tam, T. F. Chang, B. J. Wang, K. Asamura, S. Kasahara, S. Yokota, K. Keika, T. Hori, Y. Miyoshi, C. Jun, M. Shoji, and I. Shinohara (2021). First simultaneous observation of a nighttime medium-scale traveling ionospheric disturbance from the ground and a magnetospheric satellite, J. Geophys. Res., 126, https://doi.org/10.1029/2020JA029086.

  2. Miyoshi, Y., Hosokawa, K., Kurita, S., Oyama, S., et al. Penetration of MeV electrons into the mesosphere accompanying pulsating aurorae. Sci Rep 11, 13724 (2021). https://doi.org/10.1038/s41598-021-92611-3.

  3. Ozaki, M., Inoue, T., Tanaka, Y., Yagitani, S., Kasahara, Y., Shiokawa, K., Miyoshi, Y., Imamura, K., Hosokawa, K., Oyama, S., Kataoka R., Ebihara, Y., Ogawa, Y. and Kadokura A. (2021). Spatial evolution of wave-particle interaction region deduced from flash-type auroras and chorus-ray tracing. Journal of Geophysical Research: Space Physics, 126, e2021JA029254. https://doi.org/10.1029/2021JA029254.

  4. Inaba, Y., K. Shiokawa1, S. Oyama et al. (2021), Multi-event Analysis of Plasma and Field Variations in Source of Stable Auroral Red (SAR) Arcs in Inner Magnetosphere during Non-storm-time Substorms, Journal of Geophysical Research: Space Physics, 126, https://doi.org/10.1029/2020JA029081.

  5. Hosokawa, K., Y. Miyoshi, S.-I. Oyama, Y. Ogawa, S. Kurita, Y. Kasahara, Y. Kasaba, S. Yagitani, S. Matsuda, M. Ozaki, F. Tsuchiya, A. Kumamoto, T. Takashima, I. Shinohara, and R. Fujii (2021), Over-darkening of pulsating aurora, Journal of Geophysical Research: Space Physics, 126, https://doi.org/10.1029/2020JA028838.

  6. Narayanan, V. L., Nozawa, S., Oyama, S.-I., Mann, I., Shiokawa, K., Otsuka, Y., Saito, N., Wada, S., Kawahara, T. D., and Takahashi, T.: Formation of an additional density peak in the bottom side of the sodium layer associated with the passage of multiple mesospheric frontal systems, Atmos. Chem. Phys., 21, 2343–2361, https://doi.org/10.5194/acp-21-2343-2021, 2021.

  7. Takeshita Y., K. Shiokawa, Y. Miyoshi, M. Ozaki, Y. Kasahara, S. Oyama, M. Connors, J. Manninen, V. K. Jordanova, D. Baishev, A. Oinats, and V. Kurkin (2020), Study of spatiotemporal development of global distribution of magnetospheric ELF/VLF waves using ground-based and satellite observations, and RAM-SCB simulations, for the March and November 2017 storms, J. Geophys. Res., 125, https://doi.org/10.1029/2020JA028216.

  8. Tsuda, T. T., Li, C., Hamada, S., Hosokawa, K., Oyama, S., Nozawa, S., et al. (2020). OI 630.0‐nm and N2 1PG emissions in pulsating aurora events observed by an optical spectrograph at Tromsø, Norway. Journal of Geophysical Research: Space Physics, 125, e2020JA028250. https://doi.org/10.1029/2020JA028250

  9. Miyoshi, Y., Saito, S., Kurita, S., Asamura, K., Hosokawa, K., Sakanoi, T., Mitani, T., Ogawa, Y., Oyama, S., Tsuchiya, F., Jones, S. L., Jaynes, A. N., Blake, J. B. (2020). Relativistic electron microbursts as high‐energy tail of pulsating aurora electrons. Geophysical Research Letters, 47, e2020GL090360. https://doi.org/10.1029/2020GL090360

  10. Inaba Y., K. Shiokawa, S. Oyama, Y. Otsuka, A. Oksanen, A. Shinbori, A. Yu. Gololobov, Y. Miyoshi, Y. Kazama, S.-Y. Wang, S. W. Y. Tam, T.-F. Chang, B.-J. Wang, S. Yokota, S. Kasahara, K. Keika, T. Hori, A. Matsuoka, Y. Kasahara, A. Kumamoto, Y. Kasaba, M. Shoji, I. Shinohara, and C. Stolle, Plasma and field observations in the magnetospheric source region of a stable auroral red (SAR) arc by the Arase satellite on 28 March 2017, J. Geophys. Res., 125, https://doi.org/10.1029/2020JA028068, 2020.

  11. Kawamura, Y., Hosokawa, K., Nozawa, S., Oyama, S., et al. Estimation of the emission altitude of pulsating aurora using the five-wavelength photometer. Earth Planets Space 72, 96 (2020). https://doi.org/10.1186/s40623-020-01229-8

  12. Hosokawa, K., Y. Miyoshi, M. Ozaki, S.-I. Oyama, Y. Ogawa, S. Kurita, Y. Kasahara, Y. Kasaba, S. Yagitani, S. Matsuda, F. Tsuchiya, A. Kumamoto, R. Kataoka, K. Shiokawa, T. Raita, E. Turunen, T. Takashima, I. Shinohara & R. Fujii, Multiple time-scale beats in aurora: precise orchestration via magnetospheric chorus waves. Nature Sci Rep 10, 3380 (2020). https://doi.org/10.1038/s41598-020-59642-8

  13. Nanjo, S., Hozumi, Y., Hosokawa, K., Kataoka, R., Miyoshi, Y., & Oyama, S.-i. (2020). Fine-scale visualization of aurora in a wide area using color digital camera images from the International Space Station. J. Geophys. Research: Space Physics, 125, e2019JA027729. https://doi.org/10.1029/2019JA027729

  14. Yadav, S., K. Shiokawa, S. Oyama and Y. Otsuka, Multi-event analysis of oscillatory motion of medium-scale traveling ionospheric disturbances observed by a 630-nm airglow imager over Tromsø, J. Geophys. Research: Space Physics, DOI: 10.1029/2019JA027598, 2020.

  15. Nishimura, Y., Lessard, M.R., Katoh, Y. et al., Diffuse and Pulsating Aurora, Space Sci Rev, 216: 4. https://doi.org/10.1007/s11214-019-0629-3, 2020.

  16. Ogawa, Y., Y. Tanaka, A. Kadokura, K. Hosokawa, Y. Ebihara, T. Motoba, B. Gustavsson, U. Brändström, Y. Sato, S. Oyama, M. Ozaki, T. Raita, F. Sigernes, S. Nozawa, K. Shiokawa, M. Kosch, K. Kauristi, C. Hall, S. Suzuki, Y. Miyoshi, A. Gerrard, H. Miyaoka, R. Fujiit, Development of low-cost multi-wavelength imager system for studies of aurora and airglow, Polar Science, 23, 100501, https://doi.org/10.1016/j.polar.2019.100501, 2020.

  17. Xu, H., Shiokawa, K., Oyama, S. et al. High-latitude thermospheric wind study using a Fabry–Perot interferometer at Tromsø in Norway: averages and variations during quiet times. Earth Planets Space 71, 110 (2019) doi:10.1186/s40623-019-1093-8

  18. Kozlovsky, A., S. Shalimov, S. Oyama, K. Hosokawa, M. Lester, Y. Ogawa and C. Hall (2019), Ground Echoes Observed by the Meteor Radar and High-Speed Auroral Observations in the Substorm Growth Phase, J. Geophys. Res., https://doi.org/10.1029/ 0.1029/2019JA026829.

  19. Xu, H., K. Shiokawa, S. Oyama, and Y. Otsuka (2019), Thermospheric wind variations observed by a Fabry-Perot interferometer at Tromsø, Norway, at substorm onsets, Earth, Planets and Space, 71:93, https://doi.org/10.1186/s40623-019-1072-0.

  20. Tanaka, Y.-M, T. Nishiyama, A. Kadokura, M. Ozaki, Y. Miyoshi, K. Shiokawa, S. Oyama, R. Kataoka, M. Tsutsumi, K. Nishimura, K. Sato, Y. Kasahara, A. Kumamoto, F. Tsuchiya, M. Fukizawa, M. Hikishima, S. Matsuda, A. Matsuoka, I. Shinohara, M. Nose, T. Nagatsuma, M. Shinohara, A. Fujimoto, M. Teramoto, R. Nomura, A. Sessai Yukimatu, K. Hosokawa, M. Shoji and R. Latteck (2019), Direct comparison between magnetospheric plasma waves and polar mesosphere winter echoes in both hemispheres, J. Geophys. Res., https://doi.org/10.1029/2019JA026891.

  21. Takeshita, Y., K. Shiokawa, M. Ozaki, J. Manninen, S. Oyama, M. Connors, D. Baishev, V. Kurkin and A. Oinats (2019), Longitudinal extent of magnetospheric ELF/VLF waves using multipoint PWING ground stations at subauroral latitudes, Journal of Geophysical Research: Space Physics, https://doi.org/10.1029/2019JA026810.

  22. Baron, P., Ochiai, S., Dupuy, E., Larsson, R., Liu, H., Manago, N., Murtagh, D., Oyama, S., Sagawa, H., Saito, A., Sakazaki, T., Shiotani, M., and Suzuki, M.: Potential for the measurement of MLT wind, temperature, density and geomagnetic field with Superconducting Submillimeter-Wave Limb-Emission Sounder-2 (SMILES-2), Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-217, 2019.

  23. Cai, L., Oyama, S., Aikio, A., Vanhamäki, H., & Virtanen, I. (2019). Fabry-Perot interferometer observations of thermospheric horizontal winds during magnetospheric substorms. Journal of Geophysical Research: Space Physics, 124, 3709–3728. https://doi.org/10.1029/2018JA026241

  24. Kawamura, S., K. Hosokawa, S. Kurita, S. Oyama, Y. Miyoshi, Y. Kasahara, M. Ozaki, S. Matsuda, A. Matsuoka, B. Kozelov, Y. Kawamura, I. Shinohara, Tracking the region of high correlation between pulsating aurora and chorus: simultaneous observations with Arase satellite and ground-based all-sky imager in Russia, J. Geophys. Res, 10.1029/2019JA026496, 2019.

  25. Ozaki, M., Y. Miyoshi, K. Shiokawa, K. Hosokawa, S. Oyama, R. Kataoka, Y. Ebihara, Y. Ogawa, Y. Kasahara, S. Yagitani, Y. Kasaba, A. Kumamoto, F. Tsuchiya, S. Matsuda, Y. Katoh, M. Hikishima, S. Kurita, Y. Otsuka, R. C. Moore, Y. Tanaka, M. Nosé, T. Nagatsuma, N. Nishitani, A. Kadokura, M. Connors, T. Inoue, A. Matsuoka, & I. Shinohara, Visualization of rapid electron precipitation via chorus element wave–particle interactions, Nature Communications, doi:10.1038/s41467-018-07996-z, 2019.

  26. Kurita, S., Y. Miyoshi, K. Shiokawa, N. Higashio, T. Mitani, T. Takashima, A. Matsuoka, I. Shinohara, C. A. Kletzing , J. B. Blake, S. G. Claudepierre, M. Connors, S. Oyama, T. Nagatsuma, K. Sakaguchi, D. Baishev and Y. Otsuka, Rapid loss of relativistic electrons by EMIC waves in the outer radiation belt observed by Arase, Van Allen Probes, and the PWING ground stations, Geophys. Res. Lett., 45, doi:10.1029/2018GL080262, 2018.

  27. Fukizawa, M., T. Sakanoi, Y. Miyoshi, K. Hosokawa, K. Shiokawa, Y. Katoh, Y. Kazama, A. Kumamoto, F. Tsuchiya, Y. Miyashita, Y. Nose, M. Tanaka, Y. Kasahara, M. Ozaki, A. Matsuoka, S. Matsuda, M. Hikishima, S. Oyama, Y. Ogawa, S. Kurita, R. Fujii, Electrostatic electron cyclotron harmonic waves as a candidate to cause pulsating auroras, Geophys. Res. Lett., 45, doi:10.1029/2018GL080145, 2018.

  28. Ozaki, M., K. Shiokawa, Y. Miyoshi, K. Hosokawa, S. Oyama, S. Yagitani, et al., Microscopic observations of pulsating aurora associated with chorus element structures: Coordinated Arase satellite-PWING observations, Geophysical Research Letters, 45. https://doi.org/10.1029/2018GL079812, 2018

  29. Shiokawa, K., M. Ozaki, A. Kadokura, Y. Endo, T. Sakanoi, S. Kurita, Y. Miyoshi, S. Oyama, M. Connors, I. Schofield, J. Michael Ruohoniemi, M. Nose, T. Nagatsuma, K. Sakaguchi, D. G. Baishev, A. Pashinin, R. Rakhmatulin, B. Shevtsov, I. Poddelsky, M. Engebretson, Tero Raita, Y.-M. Tanaka, M. Shinohara, M. Teramoto, R. Nomura, A. Fujimoto, A. Matsuoka, N. Higashio, T. Takashima , I. Shinohara, and Jay M. Albert, Purple auroral rays and global Pc1 pulsations observed at the CIR-associated solar wind density enhancement on March 21, 2017, Geophys. Res. Lett., 45, doi:10.1029/2018GL079103, 2018.

  30. T. T. Tsuda, M. T. Rietveld, M. J. Kosch, S. Oyama, Y. Ogawa, K. Hosokawa, S. Nozawa, T. Kawabata and A. Mizuno, Survey of conditions for artificial aurora experiments by the second electron gyro-harmonic at EISCAT Tromsø using dynasonde data, Earth, Planets and Space201870:94, https://doi.org/10.1186/s40623-018-0864-y, 2018.

  31. T. T. Tsuda, M. T. Rietveld, M. J. Kosch, S. Oyama, K. Hosokawa, S. Nozawa, T. Kawabata, A. Mizuno and Y. Ogawa, Survey of conditions for artificial aurora experiments at EISCAT Tromsø using dynasonde data, Earth, Planets and Space 201870:40, https://doi.org/10.1186/s40623-018-0805-9, 2018.

  32. Shiokawa, K., Y. Kato, Y. Hamaguchi, Y. Yamamoto, T. Adachi, M. Ozaki, S. Oyama, M. Nosé, T. Nagatsuma, Y. Tanaka, Y. Otsuka, Y. Miyoshi, R. Kataoka, Y. Takagi, Y. Takeshita, A. Shinbori, S. Kurita, T. Hori, N. Nishitani, I. Shinohara, F. Tuchiya, Y. Obana, S. Suzuki, N. Takahashi, K. Seki, A. Kadokura, K. Hosokawa, Y. Ogawa, M. Connors, J. M. Ruohoniemi, M. Engebretson, E. Turunen, T. Ulich, J. Manninen, T. Raita, A. Kero, A. Oksanen, M. Back, K. Kauristie, J. Mattanen, D. Baishev, V. Kurkin, A. Oinats, A. Pashinin, R. Vasilyev, R. Rakhmatulin, W. Bristow, and M. Karjala, Ground-based instruments of the PWING project to investigate dynamics of the inner magnetosphere at subauroral latitudes as a part of the ERG-ground coordinated observation network, Earth, Planets and Space, 69:160, doi: 10.1186/s40623-017-0745-9, 2017.

  33. Nakamura, Y., K. Shiokawa, Y. Otsuka, S. Oyama, S. Nozawa. T. Komolmis, S. Komonjida, D. Neudegg, C. Yuile, J. Meriwether, H. Shinagawa, and H. Jin (2017), Measurement of thermospheric temperatures using OMTI Fabry-Perot interferometers with 70mm etalon, Earth, Planets and Space, 69:57, doi: 10.1186/s40623-017-0643-1.

  34. Turunen, E., A. Kero, P. T. Verronen, Y. Miyoshi, S.-I. Oyama, and S. Saito (2016), Mesospheric ozone destruction by high-energy electron precipitation associated with pulsating aurora, J. Geophys. Res. Atmos., 121, doi:10.1002/2016JD025015.

  35. Yatagai, A., and S. Oyama, Thermospheric Nocturnal Wind Climatology Observed by Fabry–Perot Interferometers over the Asia–Oceania Region, J. Meteorol. Soc. Japan, 94(6), doi:10.2151/jmsj.2016-026, Sep. 2016.

  36. Miyoshi, Y., S. Saito, K. Seki, T. Nishiyama, R. Kataoka, K. Asamura, Y. Katoh, Y. Ebihara, T. Sakanoi, M. Hirahara, S. Oyama, S. Kurita, and O. Santolik (2015), Relation between fine structure of energy spectra for pulsating aurora electrons and frequency spectra of whistler mode chorus waves, J. Geophys. Res. Space Physics, 120, doi:10.1002/2015JA021562.

  37. Takahashi, T., Nozawa, S., Tsuda, T. T., Ogawa, Y., Saito, N., Hidemori, T., Kawahara, T. D., Hall, C., Fujiwara, H., Matuura, N., Brekke, A., Tsutsumi, M., Wada, S., Kawabata, T., Oyama, S., and Fujii, R.: A case study on generation mechanisms of a sporadic sodium layer above Tromsø (69.6° N) during a night of high auroral activity, Ann. Geophys., 33, 941-953, doi:10.5194/angeo-33-941-2015, Aug. 2015.

  38. Hashimoto, A., K. Shiokawa, Y. Otsuka, S.-i. Oyama, S. Nozawa, T. Hori, M. Lester, and M. G. Johnsen, Statistical study of auroral fragmentation into patches, J. Geophys. Res. Space Physics, 120, doi:10.1002/2015JA021000, Aug. 2015.

  39. Miyoshi, Y., S. Oyama, S. Saito, S. Kurita, H. Fujiwara, R. Kataoka, Y. Ebihara, C. Kletzing, G. Reeves, O. Santolik, M. Clilverd, C. J. Rodger, E. Turunen, and F. Tsuchiya (2015), Energetic electron precipitation associated with pulsating aurora: EISCAT and Van Allen Probe observations. J. Geophys. Res. Space Physics, 120, 2754–2766, doi: 10.1002/2014JA020690.

  40. Ieda, A., S. Oyama, H. Vanhamäki, R. Fujii, A. Nakamizo, O. Amm, T. Hori, M. Takeda, G. Ueno, A. Yoshikawa, R. J. Redmon, W. F. Denig, Y. Kamide, and N. Nishitani, Approximate forms of daytime ionospheric conductance, J. Geophys. Res. Space Physics, 119, pages 10,397–10,415. doi:10.1002/2014JA020665, Jan. 2015.

  41. Takahashi, T., Nozawa, S., Tsutsumi, M., Hall, C., Suzuki, S., Tsuda, T. T., Kawahara, T. D., Saito, N., Oyama, S., Wada, S., Kawabata, T., Fujiwara, H., Brekke, A., Manson, A., Meek, C., and Fujii, R.: A case study of gravity wave dissipation in the polar MLT region using sodium LIDAR and radar data, Ann. Geophys., 32, 1195-1205, doi:10.5194/angeo-32-1195-2014, Oct. 2014.

  42. Shiokawa, K., A. Hashimoto, T. Hori, K. Sakaguchi, Y. Ogawa, E. Donovan, E. Spanswick, M. Connors, Y. Otsuka, S. Oyama, S. Nozawa, and K. McWilliams, Auroral fragmentation into patches, J. Geophys. Res. Space Physics, 119, 8249–8261, doi:10.1002/2014JA020050, Nov. 2014.

  43. Tsuda, T., S. Nozawa, T. D. Kawahara, T. Kawabata, N. Saito, S. Wada, Y. Ogawa, S. Oyama, C. M. Hall, M. Tsutsumi, M. K. Ejiri, S. Suzuki, T. Takahashi, T. Nakamura, Decrease in sodium density observed during auroral particle precipitation over Tromsø, Norway, GRL, 40, DOI: 10.1002/grl.50897, Oct. 2013.

  44. Shiokawa, K., M. Mori, Y. Otsuka, S. Oyama, S. Nozawa, S. Suzuki, and M. Connors, Observation of nighttime medium-scale travelling ionospheric disturbances by two 630-nm airglow imagers near the auroral zone, J. Atmos. Solar-Terr. Phys., 103, 184-194, Sep., 2013.

  45. Shiokawa, K., M. Mori, Y. Otsuka, S. Oyama, and S. Nozawa, Motion of high-latitude nighttime medium-scale traveling ionospheric disturbances associated with auroral brightening, J. Geophys. Res., 117, A10316, doi:10.1029/2012JA017928, Oct., 2012.

  46. Nozawa, S., C. M. Hall, M. Tsutsumi, A. Brekke, Y. Ogawa, T. T. Tsuda, S. Oyama, and R. Fujii, Mean winds, tides, and quasi-2 day waves above Bear Island, J. Atmos. Solar-Terr. Phys., doi: 10.1016/j.jastp.2012.05.002, Jun, 2012.

  47. Shiokawa, K., Y. Otsuka, S. Oyama, S. Nozawa, M. Satoh, Y. Katoh, Y. Hamaguchi, Y. Yamamoto, and J. Meriwether, Development of low-cost sky-scanning Fabry-Perot interferometers for airglow and auroral studies, Earth Planets Space, 64(11), 1033-1046, doi:10.5047/eps.2012.05.004, Nov, 2012.

  48. Tsuda, T. T., S. Nozawa, T. Kawahara, T. Kawabata, N. Saito, S. Wada, C. Hall, S. Oyama, Y. Ogawa, S. Suzuki, T. Ogawa, T. Takahashi, H. Fujiwara, R. Fujii, N. Matuura, and A. Brekke, Fine structure of sporadic sodium layer observed with a sodium lidar at Tromsø, Norway, Geophys. Res. Lett., 38, L18102, doi:10.1029/2011GL048685, August, 2011.

  49. Kurihara, J., Y. Ogawa, S. Oyama, S. Nozawa , M. Tsutsumi , C. Hall , Y. Tomikawa , R. Fujii,Links between a stratospheric sudden warming and thermal structures and dynamics in the high-latitude mesosphere, lower thermosphere, and ionosphere, Geophys. Res. Lett., 37, L13806, doi:10.1029/2010GL043643, Jul. 2010.

  50. Nozawa, S., Y. Ogawa, S. Oyama, H. Fujiwara, T. Tsuda, A. Brekke, C. M. Hall, Y. Murayama, S. Kawamura, H. Miyaoka, and R. Fujii, Tidal waves in the polar lower thermosphere observed using the EISCAT long run data set obtained in September 2005, J. Geophy. Res., 115, A08312, doi:10.1029/2009JA015237, Aug. 2010.

  51. Fujii, R., Y. Iwata, S. Oyama, S. Nozawa, and Y. Ogawa, Relations between proton auroras, intense electric field and ionospheric electron density depletion, J. Geophys. Res., A09304, doi:10.1029/2009JA01431, Sep. 2009.

  52. Tsuda, T. T., S. Nozawa, S. Oyama, T. Motoba, Y. Ogawa, H. Shinagawa, N. Nishitani, K. Hosokawa, N. Sato, M. Lester, and R. Fujii, Acceleration mechanism of high-speed neutral wind observed in the polar lower thermosphere, J. Geophys. Res., 114, A04322, doi:10.1029/2008JA013867, Apr. 2009.

  53. Maeda, S., Y. Ogawa, K. Hosokawa, S. Nozawa, S. Oyama, T. Tsuda and A. Brekke, Ion heating in high-speed flow channel within the duskside cell of the polar-cap ion convection under large IMF-By condition, J. Geophys. Res., A11307, doi:10.1029/2009JA014300, Nov. 2009.

  54. Kurihara, J., S. Oyama, S. Nozawa, T. T. Tsuda, R. Fujii, Y. Ogawa, H. Miyaoka, N. Iwagami, T. Abe, K.-I. Oyama, M. Kosch, A. Aruliah, E. Griffin, and K. Kauristie, Temperature enhancements and vertical winds in the lower thermosphere associated with auroral heating during the Dynamics and Energetics of the Lower Thermosphere in Aurora (DELTA) campaign, J. Geophys. Res., A12306 doi:10.1029/2009JA014392, Dec. 2009.

  55. Burton, L. M., J. A. Cohen, R. Pradipta, A. Labno, M. C. Lee, O. Batishchev, D. L. Rokusek, S. P. Kuo, B. J. Watkins, and S. Oyama, Excitation and diagnosis of cascading Langmuir waves in ionospheric plasmas at Gakona, Alaska, Phys. Scr., 014030 doi:10.1088/0031-8949/2008/T132/014030, 2008.

  56. Cohen, J. A., L. M. Burton, R. Pradipta, A. Labno, M.C. Lee, S.P. Kuo, B.J. Watkins, and S. Oyama, Ionospheric Ducts and Plasma Waves Induced by HF Heater over Gakona, Proceedings of URSI General Assembly, URSI General Assembly, Chicago, USA, 2008.

  57. Kosch M. J., T. Pedersen, E. Mishin, S. Oyama, J. Hughes, A. Senior, B. Watkins, B. Bristow, Coordinated optical and radar observations of ionospheric pumping for a frequency pass through the second electron gyroharmonic at HAARP, J. Geophys. Res., 112, A06325, doi:10.1029/2006JA012146, Jun. 2007.

  58. Kosch M. J., T. Pedersen, E. Mishin, M. Starks, E. Gerken-Kendall, D. Sentman, S. Oyama, B. Watkins, Temporal evolution of pump beam self-focusing at the High-Frequency Active Auroral Research Program, J. Geophys. Res., 112, A08304, doi:10.1029/2007JA012264, Aug. 2007.

  59. Shinagawa, H., and Oyama, S., A two-dimensional simulation of thermospheric vertical winds in the vicinity of an auroral arc, Earth Planets and Space, 58(9), 1173-1181, Sep. 2006.

  60. Shinagawa, H., S. Oyama, S. Nozawa, S. C. Buchert, R. Fujii, and M. Ishii, Thermospheric and ionosphric dynamics in the auroral region, Advances in Space Research, 31(4), 951-956, Apr. 2003.

  61. Nozawa, S., S. Imaida, A. Brekke, C. Hall, C. Meek, A. Manson, S. Oyama, K. Dobashi, and R. Fujii, The quasi 2-day wave observed in the polar mesosphere, J. Geophys. Res., 108, 10.1029/2002JD002440, Jan. 2003.

  62. Nozawa, S., H. Iwahashi, A. Brekke, C. M. Hall, C. Meek, A. Manson, S. Oyama, Y. Murayama, and R. Fujii, The quasi 2-day wave observed in the polar mesosphere (2): Comparison of the characteristics observed at Tromso and Poker Flat, J. Geophys. Res., 108 , 101029/2002JD003221, Dec. 2003.

  63. Fujii, R., S. Oyama, S. C. Buchert, S. Nozawa, and N. Matuura, Field-aligned ion motions in the E and F region, J. Geophys. Res., 107, 10.1029/ 2001JA900148, May 2002.

  64. Nozawa, S., A. Brekke, A. Manson, C. M. Hall, C. Meek, K. Morise, S. Oyama, K. Dobashi, and R. Fujii, A comparison study of the auroral lower thermopsheric neutral winds derived by the EISCAT UHF radar and the Tromso radar, J. Geophys. Res., 107, 10.1029/2000JA007581, Aug. 2002.

  65. Ishii, M., S. Oyama, S. Nozawa, R. Fujii, E. Sagawa, S. Watari, and H. Shinagawa, Dynamics of neutral wind in the polar region observed with two Fabry-Perot interferometers, Earth Planets Space, 51, 833-844, Jul. 1999.

 

Supplements

  1. Oyama, S., S. Nozawa, R. Fujii, K. Shiokawa, Y. Otsuka, and T. T. Tsuda, Optical instruments of STEL, Nagoya University at the EISCAT radar site in Tromsø, Norway, CAWSES-II Kickoff Symposium in Japan, Proceedings, 113-116. 2010.

  2. Nozawa, S., Y. Ogawa, S. Oyama, H. Miyaoka, T. Kawahara, T. T. Tsuda, and M. Tsutsumi, Research on the lower thermosphere and mesosphere using EISCAT radars, and other instruments, CAWSES-II Kickoff Symposium in Japan, Proceedings, 46-48, 2010.

  3. Kurihara, J., Y. Ogawa, S. Oyama, S. Nozawa, M. Tsutsumi, C. M. Hall, Y. Tomikawa, and R. Fujii, Links between a stratospheric sudden warming and thermal structures and dynamics in the high-latitude mesosphere, lower thermosphere, and ionosphere, CAWSES-II Kickoff Symposium in Japan, Proceedings, 51-52, 2010.

  4. Ogawa, Y., and EISCAT Japan project team, Long-term variations of the polar ionosphere and thermosphere observed with European Incoherent Scatter (EISCAT) radars, CAWSES-II Kickoff Symposium in Japan, Proceedings, 76-78, 2010.

  5. Tsuda, T. T., S. Nozawa, T. D. Kawahara, T. Kawabata, S. Oyama, R. Fujii, Y. Ogawa, N. Saito, S. Wada, A. Brekke, and C. M. Hall, A sodium lidar project at Tromsø, Norway: First report on test observations at Wako, Japan, CAWSES-II Kickoff Symposium in Japan, Proceedings,121-124, 2010.

  6. Oyama, S., and B. J. Watkins, Artificial ionospheric irregularities measured with the MUIR (Modular UHF Ionospheric Radar) at HAARP (High Frequency Active Auroral Research Program), National Institute of Information and Communications Technology, Seasonal Report, 53(1/2), 95-102, 2007.

  7. Oyama, S., Y. Murayama, M. Ishii, M. Kubota Development of SALMON system and the environment data transfer experiment, Journal of Communications Research Laboratory, 2002.

 

 

Invited talk

  1. Oyama, S. and SDI-3D project team, SDI-3D project, 44th Apatity Seminar, online, 2021/03.

  2. Oyama, S., A. Aikio, H. Vanhamäki, A. Shinbori, M. Rietveld, Y. Ogawa, M. Kellinsalmi, T. Raita, K. Shiokawa, I. Virtanen, L. Cai, A. Workayehu, M. Pedersen, K. Kauristie, B. Kozelov and A. Demekhov, Thermospheric wind acceleration in the ionospheric trough for Kp = 0+, COSPAR 2021, online, January 2021.

  3. Oyama, S. and SDI-3D project team, SDI-3D, CHAMOS workshop 2020, remote meeting, October 2020.

  4. 大山伸一郎, 「超高層大気におけるN-I結合の理解に向けた衛星－地上共同観測への期待」, 宇宙空間からの地球超高層大気観測に関する研究会, 遠隔開催, September 2020.

  5. 大山伸一郎, 「極域熱圏風加速の空間分布とSDIによる二次元測定の重要性」, 中間圏・熱圏・電離圏 (MTI) 研究集会, 遠隔開催, September 2020.

  6. Oyama, S., PWING: Global observation network along 60˚N, Sirius public lecture in Jyvaskyla, Finland, October 2019.

  7. Oyama, S., M. Conde, A. Aikio, H. Vanhamäki, I. Virtanen, L. Cai, E. Turunen, T. Ulich, K. Kauristie, U. Brandström, and SDI-3D project team, New insights found from coalescence of the ionospheric and thermospheric measurements at auroral latitudes, The 45th Annual European Meeting on Atmospheric Studies by Optical Methods, Kiruna, Sweden, August 2018.

  8. Oyama, S., A. E. Kero, C. Rodger, M. A. Clilverd, Y. Miyoshi, N. Partamies, E. Turunen, T. Raita, P. T. Verronen, S. Saito, K. Hosokawa, Y. Ogawa, S. Kurita, S. Nozawa, H. Miyaoka, Y. Tanaka, and R. Fujii, Coordinated observations with the ground-based instruments and satellites to study energetic electron precipitation and auroral morphology at the substorm recovery phase, International HEPPA-SOLARIS Workshop, Roanoke, USA, June 2018.

  9. Oyama, S., A. Aikio, M. Conde, H. Vanhamäki, I. Virtanen, L. Cai, K. Kubota, T. Morinaga, T. T. Tsuda, J. Kurihara, M. F. Larsen, M. Yamamoto, M. Hirahara, and K. Shiokawa, New insights found from coalescence of the ionospheric and thermospheric measurements at auroral latitudes, JpGU 2018, Makuhari Japan, May 2018.

  10. Oyama, S., K. Shiokawa, A. Aikio, L. Cai, M. Hirahara, B. J. Watkins, C. T. Fallen, M. G. Conde, and A. Yatagai, Dependency of the thermospheric dynamics on the auroral morphology, ISROSES-III, Varna, Bulgaria, September 2016.

  11. 大山伸一郎, 「宇宙からオーロラを見るとなぜドーナツ状になっているのか？」, 名古屋大学ホームカミングデー　講演・体験企画「太陽から地球まで」, 名古屋, October 2014.

  12. 大山伸一郎, Discrete Aurora 近傍の電流系概論, 中間圏・熱圏・電離圏研究集会, 小金井, September 2014.

  13. Oyama, S., J. Kurihara, T. T. Tsuda, K. Shiokawa, Y. Miyoshi, B. J. Watkins, Thermospheric wind variations in the pulsating aurora, Asia Oceania Geosciences Society, Sapporo, July 2014.

  14. Oyama, S., Aurora and thermospheric dynamics, Japan-Norway symposium on Space Science in Polar Region, Oslo, June, 2012.

  15. Oyama, S., Small-scale thermospheric wind dynamics at high latitudes, STEL-KASI workshop, Nagoya, October 2010.

  16. Oyama, S., Small-scale auroral GW observations, ISSI-workshop coupling, Bern, Switzerland, September, 2010.

  17. Oyama, S., S. Nozawa, R. Fujii, K. Shiokawa, Y. Otsuka, and T. T. Tsuda, Report of the STEL optical observation at the northern Scandinavia by March 2010, Japan Geoscience Union Meeting 2010, Makuhari, May 2010.

  18. Oyama, S., S. Maeda, H. Shinagawa, and B. J. Watkins, Vertical motions in the polar lower thermosphere/ionosphere: Recent results from the incoherent-scatter radar, GSSS-2007, Greenland, May 2007.

​

​

Oral/Poster presentation (international only; since 2005)

  1. Oyama, S., Miyamoto Taishiro, Tero Raita, Keisuke Hosokawa, Yoshizumi Miyoshi, Yasunobu Ogawa, and Satoshi Kurita, A case study to estimate energy spectra of pulsating auroral electrons from cosmic noise absorption and auroral brightness, 44th Apatity Seminar, online, March 2021.

  2. Oyama, S., A. Aikio, H. Vanhamäki, A. Shinbori, M. Rietveld, Y. Ogawa, M. Kellinsalmi, T. Raita, K. Shiokawa, I. Virtanen, L. Cai, A. Workayehu, M. Pedersen, K. Kauristie, B. Kozelov and A. Demekhov, Event study of the M-I-T coupling in the ionospheric trough region for Kp = 0+, PWING-ERG workshop, online, March 2021.

  3. Oyama, S., A. Shinbori, Y. Ogawa, M. Kellinsalmi, T. Raita, M. Rietveld, A. Aikio, H. Vanhamäki, K. Shiokawa, I. Virtanen, L. Cai, A. B. Workayehu, M. Pedersen, K. Kauristie, T. T. Tsuda, B. Kozelov, A. Demekhov, A. Yahnin, F. Tsuchiya, A. Kumamoto, Y. Kasahara, A. Matsuoka, M. Shoji and M. Teramoto, An event study of the M-I-T coupling at a pseudo breakup during geomagnetically quiet conditions, AGU Fall Meeting, online, December 2020.

  4. Oyama, S., Anita Aikio, Heikki Vanhamaki, Atsuki Shinbori, Mike Rietveld, Yasunobu Ogawa, Mirjam Kellinsalmi, Tero Raita, Kazuo Shiokawa, Ilkka Virtanen, Lei Cai, Abiyot Workayehu, Marcus Pedersen, Kirsti Kauristie, Boris Kozelov and Andrei Demekhov, Thermospheric wind acceleration in the ionospheric trough for Kp = 0+, JpGU 2020, online, July 2020.

  5. Oyama, S., Atsuki Shinbori, Anita Aikio, Heikki Vanhamaki, Yasunobu Ogawa, Mirjam Kellinsalmi, Tero Raita, Mike Rietveld, Kazuo Shiokawa, Ilkka Virtanen, Lei Cai, Abiyot Workayehu, Marcus Pedersen, Kirsti Kauristie, Boris Kozelov and Andrei Demekhov, SAR arc at 68o geomagnetic (71o geographic) North for Kp = 0+, JpGU 2020, online, July 2020.

  6. Oyama, S., A. Aikio, H. Vanhamäki, A. Shinbori, M. Rietveld, Y. Ogawa, M. Kellinsalmi, T. Raita, K. Shiokawa, I. Virtanen, L. Cai, A. Workayehu, M. Pedersen, K. Kauristie, B. Kozelov and A. Demekhov, SAR arc at 68˚ geomagnetic (71˚ geographic) North for Kp = 0+, Apatity Seminar 2020, Apatity, Russia, March 2020

  7. Oyama, S., Anita Aikio, Heikki Vanhamaki, Yasunobu Ogawa, Atsuki Shinbori, Mike Rietveld, Mirjam Kellinsalmi, Abiyot Workayehu, Marcus Pedersen, Diversity of the auroral-subauroral ionosphere and thermosphere during very low Kp condition, Observatory Days 2020, Sodankyla, Finland, January 2020

  8. Oyama, S., Anita Aikio, Mark G. Conde, Heikki Vanhamäki, Ilkka Virtanen, Thomas Ulich, Urban Bröndström, Pekka Verronen, Monika Anderson, Niilo Kalakoski, Lassi Roininen, Sari Lasanen, Abiyot Workayehu, Kazuo Shiokawa, Heqiucen Xu, Mamoru Ishii, Masafumi Hirahara, Takeshi Sakanoi, Masato Kagitani, Juha Sorri, Tomi Teppo, Yoshimasa Tanaka, Christopher Fallen, Brenton J. Watkins, Mikko Orispää, Yasunobu Ogawa, Lei Cai, Esa Turunen, Kirsti Kauristie, Takuo T. Tsuda, and Junichi Kurihara, Spatial distribution of the polar thermospheric wind acceleration and importance of the 2D measurement with SDIs, AGU Fall Meeting 2019, San Francisco, USA, December 2019

  9. Oyama, S., Proposed Projects 2019: related to the CHAMOS activity, CHAMOS meeting, Helsinki, Finland, October 2019

  10. Oyama, S., Anita Aikio, Mark G. Conde, Heikki Vanhamäki, Ilkka Virtanen, Thomas Ulich, Urban Bröndström, Pekka Verronen, Monika Anderson, Niilo Kalakoski, Lassi Roininen, Sari Lasanen, Abiyot Workayehu, Kazuo Shiokawa, Heqiucen Xu, Mamoru Ishii, Masafumi Hirahara, Takeshi Sakanoi, Masato Kagitani, Juha Sorri, Tomi Teppo, Yoshimasa Tanaka, Christopher Fallen, Brenton J. Watkins, Mikko Orispää, Yasunobu Ogawa, Lei Cai, Esa Turunen, Kirsti Kauristie, Takuo T. Tsuda, and Junichi Kurihara, Spatial distribution of the polar thermospheric wind acceleration and importance of the 2D measurement with SDIs, EISCAT symposium, Oulu, Finland, August 2019

  11. Oyama, S., Anita Aikio, Mark G. Conde, Heikki Vanhamäki, Ilkka Virtanen, Thomas Ulich, Lassi Roininen, Pekka Verronen, Takeshi Sakanoi, SDI-3D project team, Spatial distribution of the polar thermospheric wind acceleration and importance of the 2D measurement, SuperDARN workshop, Fujiyoshida, May 2019

  12. Oyama, S., Anita Aikio, Mark G. Conde, Heikki Vanhamäki, Ilkka Virtanen, Thomas Ulich, Urban Bröndström, Pekka Verronen, Monika Anderson, Niilo Kalakoski, Lassi Roininen, Sari Lasanen, Abiyot Workayehu, Kazuo Shiokawa, Heqiucen Xu, Mamoru Ishii, Masafumi Hirahara, Takeshi Sakanoi, Masato Kagitani, Juha Sorri, Tomi Teppo, Yoshimasa Tanaka, Christopher Fallen, Brenton J. Watkins, Mikko Orispää, Yasunobu Ogawa, Lei Cai, Esa Turunen, Kirsti Kauristie, Takuo T. Tsuda, and Junichi Kurihara, Spatial distribution of the polar thermospheric wind acceleration and importance of the 2D measurement, JpGU 2019, Makuhari, May 2019

  13. Oyama. S., Anita Aikio, Mark G. Conde, Heikki Vanhamäki, Ilkka Virtanen, Thomas Ulich, Urban Bröndström, Pekka Verronen, Monika Anderson, Niilo Kalakoski, Lassi Roininen, Sari Lasanen, Abiyot Workayehu, Kazuo Shiokawa, Heqiucen Xu, Mamoru Ishii, Masafumi Hirahara, Takeshi Sakanoi, Masato Kagitani, Juha Sorri, Tomi Teppo, Yoshimasa Tanaka, Christopher Fallen, Brenton J. Watkins, Mikko Orispää, Yasunobu Ogawa, Lei Cai, Esa Turunen, Kirsti Kauristie, Takuo T. Tsuda, and Junichi Kurihara, SDI-3D project: MIT coupling study with the EISCAT_3D, EISCAT_3D user meeting, Uppsala, Sweden, May 2019

  14. Oyama, S., A. Aikio, M. G. Conde, H. Vanhamaki, I. Virtanen, T. Ulich, U. Brondstrom, P. Verronen, L. Roininen, Sari Lasanen, A. Workayehu, K. Shiokawa, Heqiucen Xu, M. Ishii, M. Hirahara, T. Sakanoi, Y. Tanaka, C. Fallen, B. J. Watkins, M. Orispaa, Y. Ogawa, L. Cai, E. Turunen, and K. Kauristie, SDI-3D project: MIT coupling study with the EISCAT_3D, Observatory Days 2019, Sodankyla, Finland, January 2019

  15. Oyama, S., A. Aikio, L. Cai, M. G. Conde, E. Turunen, K. Kauristie, H. Vanhamäki, I. Virtanen, U. Brändström, T. Ulich, A. Workayehu, K. Shiokawa, Heqiucen Xu, M. Ishii, M. Hirahara, T. Sakanoi, Y. Tanaka, C. Fallen, B. J. Watkins, M. Orispää, and Y. Ogawa, Dynamics of the polar thermospheric wind and substorm phases, AGU Fall Meeting, Washington, D.C., December 2018

  16. Oyama, S., Mark G. Conde, Anita Aikio, Esa Turunen, Kirsti Kauristie, Heikki Vanhamäki, Ilkka Virtanen, Urban Brändström, Thomas Ulich, Lei Cai, Abiyot Workayehu, Kazuo Shiokawa, Mamoru Ishii, Masafumi Hirahara, Takeshi Sakanoi, Yoshimasa Tanaka, Cristopher Fallen, and Brenton J. Watkins, SDI-3D project: measurements of the thermosphere, 2nd Nordic Observatory Meeting, Abisko, Sweden, October 2018

  17. Oyama, S., Ken KUBOTA, Takatoshi MORINAGA, Takuo TSUDA, Junichi KURIHARA, Miguel LARSEN, Masa-Yuki YAMAMOTO, Lei CAI, Simultaneous FPI and TMA Measurements of the Lower-thermospheric Wind in the Vicinity of the Poleward-expanding Aurora After Substorm Onset, AOGS, Honolulu, USA, June 2018

  18. Oyama, S., Mark G. Conde, Anita Aikio, Esa Turunen, Kirsti Kauristie, Heikki Vanhamäki, Ilkka Virtanen, Urban Brändström, Thomas Ulich, Lei Cai, Abiyot Workayehu, Kazuo Shiokawa, Mamoru Ishii, Masafumi Hirahara, Cristopher Fallen, Brenton J. Watkins, SDI-3D project: measurements of the thermosphere, EISCAT_3D user meeting, Uppsala, Sweden, May 2018

  19. Oyama, S., Antti Kero, Craig J. Rodge, Mark A. Clilverd, Yoshizumi Miyoshi, Noora Partamies, Esa Turunen, Tero Raita, Pekka T. Verronen, and Shinji Saito, Energetic electron precipitation and auroral morphology at the substorm recovery phase, ISAR-5, Tokyo, January 2018

  20. Oyama, S., Anita Aikio, Mark Conde, Heikki Vanhamaki, Ilkka Virtanen, Lei Cai, Esa Turunen, Antti Kero, Thomas Ulich, and Pekka Verronen, Beyond present understanding of Magnetosphere-Ionosphere-Thermosphere-Mesosphere coupled system at high latitudes: planning instruments to be collaborated with the EISCAT_3D, Sodankyla Observatory Days, Sodankyla, Finland, January 2018

  21. Oyama, S., A. Kero, C. J. Rodger, M. A. Clilverd, Y. Miyoshi, N. Partamies, E. Turunen, T. Raita, P. T. Verronen, and S. Saito, Energetic electron precipitation and auroral morphology at the substorm recovery phase, AGU Fall meeting, New Orleans, USA, December 2017

  22. Oyama, S. and SMILES-2 team, SMILES-2, CHAMOS workshop, Helsinki, October 2017

  23. Oyama, S., Y. Miyoshi, K. Hosokawa, K. Shiokawa, PWING team, PsA team, ARASE and Japanese observation activities at northern high latitudes, CHAMOS workshop, Helsinki, October 2017

  24. Oyama, S., PULSTAT study (energetic particle precipitation effects on the ionosphere), CHAMOS workshop, Helsinki, October 2017

  25. Oyama, S., Kazuo Shiokawa, Yoshizumi Miyoshi, Keisuke Hosokawa, Brenton J. Watkins, Junichi Kurihara, Takuo T. Tsuda, and Christopher T. Fallen, Lower thermospheric wind variations in auroral patches during the substorm recovery phase, EISCAT workshop, Tokyo, May 2017

  26. Oyama, S., A. Kero, C. J. Rodger, M. A. Clilverd, Y. Miyoshi, N. Partamies, E. Turunen, T. Raita, P. T. Verronen, and S. Saito, Energetic electron precipitation and auroral morphology at the substorm recovery phase, EISCAT workshop, Tokyo, May 2017

  27. Oyama, S., A. Kero, C. J. Rodger, M. A. Clilverd, Y. Miyoshi, N. Partamies, E. Turunen, T. Raita, P. T. Verronen, and S. Saito, Energetic electron precipitation and auroral morphology at the substorm recovery phase, JPGU 2017, Makuhari, May 2017

  28. Oyama, S., Kazuo Shiokawa, Yoshizumi Miyoshi, Keisuke Hosokawa, Brenton J. Watkins, Junichi Kurihara, Takuo T. Tsuda, and Christopher T. Fallen, Lower-thermospheric wind variations in auroral patches during the substorm recovery phase, AGU, December 2016.

  29. Oyama, S., Introduction of the EMCCD camera at the SGO site, CHAMOS meeting, Luosto, Finland, November 2016.

  30. Oyama, S., Next Target of PULSTAT, CHAMOS meeting, Luosto, Finland, November 2016.

  31. Oyama, S., K. Shiokawa, A. Aikio, L. Cai, M. Hirahara, B. J. Watkins, C. T. Fallen, M. G. Conde, and A. Yatagai, Dependency of the thermospheric dynamics on the auroral morphology, International Symposium on Recent Observations and Simulations of the Sun-Earth System III, Golden Sands, Varna, Bulgaria, September 2016.

  32. Oyama, S., Kazuo Shiokawa, Yoshizumi Miyoshi, Keisuke Hosokawa, Brenton J. Watkins, Junichi Kurihara, Takuo T. Tsuda, and Christopher T. Fallen, Lower-thermospheric wind variations in auroral patches during the substorm recovery phase, Mini-workshop on the generation/propagation of plasma waves in the Earth's inner magnetosphere, Tokyo, August 2016.

  33. Oyama, S., Yoshizumi Miyoshi, Shinji Saito, Antti Kero, Esa Turunen, Jyrki Manninen, Tero Raita, Noora Partamies, Pekka T. Verronen, Craig Rodger, Mark Clilverd, Correspondence of evolution of EEP with auroral-patch morphological changes at the substorm recovery phase, HEPPA-SOLARIS 2016, Helsinki, Finland, June 2016.

  34. Oyama, S., Kazuo Shiokawa, Satonori Nozawa, Yuichi Otsuka, Yoshizumi Miyoshi, Esa Turunen, Anita Aikio, Lei Cai, National/International joint studies with the Tromsø OMTI for studying the polar upper atmosphere, JPGU, May 2016.

  35. Oyama, S., Yoshizumi Miyoshi, Shinji Saito, Esa Turunen, Antti Kero, Noora Partamies, Pekka T Verronen, Jyrki Manninen, Ilkka Virtanen, Tero Raita, International joint study of EEP effects on the atmospheric minor components during pulsating aurora, JPGU, May 2016.

  36. Oyama, S., Status of the Japanese pulsating auroral study, 2015 CHAMOS workshop, Luosto, Finland, December 2015.

  37. Oyama, S., PULSTAT, 2015 CHAMOS workshop, Luosto, Finland, December 2015.

  38. Oyama, S.,Y. Miyoshi, S. Saito, E. Turunen, A. Kero, P. T. Verronen, and I. Virtanen,Energetic electron impacts on the atmosphere: groundbased observations with EISCAT radars and optical instruments,Founding Symposium for the Institute for Space-Earth Environment Research "Evolution of the Space-Sun-Earth Environmental system in space
    and time", Nagoya, November 2015.

  39. Oyama, S.,EISCAT and optical observations of energetic electron precipitations associated with PsA,Workshop on Energetic Particle Precipitations and its Impacts on Middle Atmosphere, Nagoya, June 2015.

  40. Oyama, S.,Y. Miyoshi, E. Turunen, S. Saito, A. Kero, P. T. Verronen, and I. Virtanen,Impacts of the pulsating aurora on the atmosphere,EISCAT_3D user meeting, Uppsala, Sweden, March 2015.

  41. Oyama, S., Kazuo Shiokawa, Yoshizumi Miyoshi, Keisuke Hosokawa, Brenton J. Watkins, Junichi Kurihara, and Takuo T. Tsuda, Lower-thermospheric winds and auroral fragmentation into patches at the substorm recovery phase, GRAND CHALLENGE BRAIN STORMING SESSION, IN THEORY, NUMERICAL, EXPERIMENTAL, TECHNOLOGY AND INSTRUMENTATION, FOR ADVANCING COORDINATED GROUND AND SOUNDING ROCKET MISSIONS, JAXA, January 2015

  42. Oyama, S., J. Kurihara, T. T. Tsuda, K. Shiokawa, Y. Miyoshi, and B. J. Watkins, Asia Oceania Geosciences Society, Sapporo, July 2014.

  43. Oyama, S., J. Kurihara, T. T. Tsuda, K. Shiokawa, Y. Miyoshi, and B. J. Watkins, Ionospheric effects on the lower-thermospheric wind in the vicinity of nightside poleward expanding aurora after substorm onset, ICS-12, Ise-Shima, November 2014.

  44. Oyama, S., K. Hosokawa, Y. Miyoshi, K. Shiokawa, J. Kurihara, T. T. Tsuda, and B. J. Watkins, A proposal to the dissipated energy budget in the auroral ionosphere at the substorm recovery phase: Challenge from thermospheric wind variations in the pulsating aurora, AGU Fall Meeting, December 2014.

  45. Oyama, S., M. K. Ejir, S. Suzuki, K. Shiokawa, T. Nakamura, M. Tsutsumi, Y. Tomikawa, T. T. Tsuda, S. Nozawa, T. Takahashi, CHARACTERISTICS OF THE MESOSPHERIC GRAVITY WAVES DERIVED FROM OH AIRGLOW IMAGES AT TROMSOE, NORWAY, Third International Symposium on the Arctic Research, Tokyo, January, 2013.

  46. Oyama, S., S. Nozawa, R. Fujii, K. Shiokawa, Y. Otsuka, T. Takahashi, CURRENT STATUS OF THE STEL OPTICAL OBSERVATIONS AT THE TROMSOE EISCAT RADAR SITE, Third International Symposium on the Arctic Research, Tokyo, January, 2013.

  47. Oyama, S., S. Suzuki, K. Shiokawa, M. K. Ejiri, T. Nakamura, M. Tsutsumi, Y. Tomikawa, T. T. Tsuda, S. Nozawa, and T. Takahashi, Researching activity of the mesospheric gravity wave with optical instruments at Tromsoe, Norway, Antarctic Gravity Wave Imaging Network workshop, Tokyo, March 2013.

  48. Oyama, S., J. Kurihara, B. J. Watkins, T. T. Tsuda, and T. Takahashi, Temporal variations of the ion-neutral collision frequency in the polar lower ionosphere during periods of geomagnetic disturbances, The 16th EISCAT international symposium, Lancaster, UK, August 2013.

  49. Oyama, S., J. Kurihara, T. T. Tsuda, Y. Miyoshi, K. Shiokawa, and B. J. Watkins, Height-dependent ionospheric responses associated with substorm onset measured with the EISCAT UHF radar, The 16th EISCAT international symposium, Lancaster, UK, August 2013.

  50. Oyama, S., S. Nozawa, R. Fujii, K. Shiokawa, Y. Otsuka, T. T. Tsuda, and T. Takahashi, STEL optical observations at the Tromsø EISCAT radar site by March 2013 and contributions to CAWSES-II, the International CAWSES-II Symposium, November, 2013.

  51. Oyama, S., J. Kurihara, T. T. Tsuda, Y. Miyoshi, K. Shiokawa, and B. J. Watkins, Height-dependent ionospheric responses around auroras associated with substorm onset measured with the EISCAT UHF radar, the International CAWSES-II Symposium, November, 2013.

  52. Oyama, S., Y. Miyoshi, K. Shiokawa, J. Kurihara, T. T. Tsuda, and B. J. Watkins, Ionospheric/lower-thermospheric variations in the vicinity of night-side poleward expanding aurora around substorm onset, American Geophysical Union Fall meeting 2013, December, 2013.

  53. Oyama, S., Aurora and thermospheric dynamics, Japan-Norway symposium on Space Science in Polar Region, Oslo, June, 2012.

  54. Oyama, S., Shiokawa K., Suzuki S., Nozawa S., Otsuka Y., Tsutsumi M., Hall C. M., Meek C., and Manson A., Characteristics of the mesospheric gravity wave observed with an all-sky camera at Tromsoe, Norway in 2009-2010, The 4thIAGA/ICMA/CAWSES-II TG4 Workshop, Prague, Czech, February 2011.

  55. Oyama, S., Kazuo Shiokawa, Satonori Nozawa, Yuichi Otsuka, Masaki Tsutsumi, Shin Suzuki, Chris M. Hall, Chris Meek, and Alan Manson, Propagation characteristics of nighttime mesospheric waves observed with an all-sky camera at Tromsoe, Norway in 2009-2010, 38th COSPAR Scientific Assembly 2010, Bremen, Germany, July, 2010.

  56. Oyama, S., Small-scale auroral GW observation, ISSI Earth Science Workshop, Bern, Switzerland, September 2010.

  57. Oyama, S., Small-scale thermospheric wind dynamics at high latitudes, STEL-KASI workshop, Nagoya Japan, October 2010.

  58. Oyama, S., K. Shiokawa, S. Suzuki, S. Nozawa, Y. Otsuka, M. Tsutsumi, C. M. Hall, C. Meek, and A. H. Manson, Propagation direction of the nighttime mesospheric gravity waves in the OH airglow images at Tromsø, Norway in winter 2009, 2010 AGU Fall Meeting, San Francisco, December 2010.

  59. Oyama, S., S. Nozawa, R. Fujii, and T. T. Tsuda, Estimation of the layered ionospheric conductance using data taken with the multi-wavelength photometer and the EISCAT UHF radar, 14th International EISCAT workshop, 2009.

  60. Oyama, S., K. Shiokawa, J. Kurihara, S. Nozawa, T. T. Tsuda, Y. Koizumi-Kurihara, Y. Otsuka, M. Tsutsumi, C. M. Hall, C. Meek, and A. Manson, Initial reports of DELTA-2 campaign: tides measured with FPI, MF radar, and meteor radar, 14th International EISCAT workshop, 2009.

  61. Oyama, S., K. Shiokawa, J. Kurihara, S. Nozawa, T. T. Tsuda, R. Fujii, and Y. Otsuka, Initial reports of DELTA-2 campaign: results from FPI and all-sky cameras, 14th International EISCAT workshop, 2009.

  62. Oyama, S. and B. J. Watkins, Aspect sensitivity of the first 100 ms HF-modification measured with the MUIR at HAARP, 13th EISCAT workshop, 2007.

  63. Oyama, S., S. Maeda, H. Shinagawa, and B. J. Watkins, Physical mechanism to generate vertical motions in the polar lower thermosphere, 13th EISCAT workshop, 2007.

  64. S. Oyama, T. Watanabe, R. Fujii, S. Nozawa, Estimation of the Polar Ionospheric Conductance Using Data from the EISCAT Radar and the Multi-wavelengths Photometer, International CAWSES Symposium, 2007.

  65. S. Oyama, and B. J. Watkins, Aspect angle dependency of the HF modification measured with MUIR at HAARP, AGU Fall Meeting, 2007.

  66. Oyama, S., B. J. Watkins, R. T. Parris, and C. J. Heinselman, Initial high-range resolution results using MUIR at HAARP, RF Ionospheric Interaction Workshop, 2006.

  67. Oyama, S., B. J. Watkins, and F. T. Djuth, HF induced plasma lines measured with the HAARP AMISR during January/February 2005 campaign, RF ionospheric interaction workshop, 2005.

  68. Oyama, S., B. J. Watkins, S. Maeda, S. Nozawa, C. Lathuillere, and W. Kofman, Methodology for estimation of the lower thermospheric wind with the incoherent-scatter radar, CEDAR workshop, 2005.