Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Rumi Nakamura is active.

Publication


Featured researches published by Rumi Nakamura.


Journal of Geophysical Research | 1994

Particle and field signatures during pseudobreakup and major expansion onset

Rumi Nakamura; D. N. Baker; T. Yamamoto; R. D. Belian; Edgar A. Bering; J. R. Benbrook; J.R. Theall

The temporal and spatial scales of the onset of two types of substorm events are investigated. These substorms were cases where the expansion onset had precursor localized auroral activation without significant negative bay enhancement, that is, “pseudobreakup”. High-resolution energetic particle and magnetic field data at synchronous orbit are used for the analysis together with auroral and magnetic field data simultaneously taken from ground-based instrumentation. The auroral structure following the pseudobreakup significantly resembled the major expansion aurora, except in its spatial scale. Typical magnetospheric onset signatures such as tail current diversion, dipolarization, and injection were observed associated with some of the pseudobreakups. The major expansion, on the other hand, consisted of a number of rather localized injections and expansions, each of which had timescales of 2-8 min, a comparable timescale to that of pseudobreakups. This study shows that there does not appear to be any phenomenological differences between pseudobreakups and major expansion onsets. The major difference between pseudobreakups and major expansion onsets would be the number of occurrences, as well as the intensity and the scale size of the magnetospheric source.


Journal of Geophysical Research | 1993

Equatorward and poleward expansion of the auroras during auroral substorms

Rumi Nakamura; Takasi Oguti; T. Yamamoto; S. Kokubun

Using all-sky TV auroral data with high spatial and temporal resolution, the formation of the auroral bulge is investigated. We show how the discrete auroral structures within the poleward expanding bulge develop systematically toward the west, the east, and also equatorward from a localized breakup region. Auroral structure at the western end of the bulge (a surge) develops with clockwise rotation as viewed along the magnetic field direction. At the eastern part of the bulge, thin auroral features propagate eastward from the breakup region. Around the central meridian of the bulge, auroral features expand equatorward and become north-south aligned (the N-S aurora). The N-S aurora and the eastward propagating aurora develop into diffuse and pulsating aurora after the expansion. We suggest that these discrete auroral structures in the bulge develop along the plasma streamlines in a localized distorted two-cell equipotential distribution; the negative potential peak is concentrated at the western part of the bulge and the positive potential region is spread poleward of the eastward propagating aurora. Equatorward expansion of auroral structures would be attributed in this scenario to the subsequent earthward transport of plasma from the onset region. Energetic particles would also be injected at the N-S auroral region as well as to the east of the region and would trigger the pulsating auroral activity. Poleward expansion, on the other hand, would be produced by the tailward motion of the onset region in accordance with the tailward moving current disruption region.


Archive | 2006

Oscillations of flux tube slippage in the quiet plasma sheet

A. A. Petrukovich; W. Baumjohann; Rumi Nakamura; A. Runov; Andre Balogh


Archive | 2010

Hayabusa AMICA V1.0

J. Saito; Toru M. Nakamura; Hidehisa Akiyama; Hirohide Demura; Budi Dermawan; Masato Furuya; Tetsuharu Fuse; Robert W. Gaskell; Takashi Hashimoto; Yusuke Higuchi; Kensuke Hiraoka; Naru Hirata; Chikatoshi Honda; Tetsuya Honda; Motoyuki Ishiguro; Kohei Kitazato; Shingo Kobayashi; Toru Kubota; Naoko Matsumoto; Tatsuhiro Michikami; Hiroyuki Miyamoto; Akiko M. Nakamura; Rumi Nakamura; E. Nemoto; Sho Sasaki; C. Shinohara; Peter W. H. Smith; Akito Sogame; J. Terazono; David J. Tholen


Archive | 2006

Global Properties of 25143 Itokawa Observed by Hayabusa

Akihiko Fujiwara; Junichiro Kawaguchi; K. Uesugi; D. K. Yeomans; J. Saito; Masanao Abe; Toshiharu Mukai; Masaru Kato; Takashi Okada; Masatoshi Yoshikawa; Hajime Yano; Hirohide Demura; D. Scheers; Robert W. Gaskell; O. S. Barnouin-Jha; Andrew F. Cheng; Hiroyuki Miyamoto; Naru Hirata; Rumi Nakamura; Sho Sasaki; Akiko M. Nakamura


Archive | 2011

Geological Structure from Anorthosite Distribution of the Lunar South Pole-Aitken Basin Based on Data Derived from SELENE Multiband Imager

K. Uemoto; M. Ohtake; J. Haruyama; Tadashi Matsunaga; Yusuke Yokota; Rumi Nakamura; T. Morota; S. Yamamoto; Shingo Kobayashi; Takahiro Iwata


Archive | 2010

Olivine Fragments in Dhofar 307 Lunar Meteorite and Surface Materials of the Farside Large Basins

Hiroyuki Takeda; Shingo Kobayashi; Akira Yamaguchi; Mayumi Otsuki; M. Ohtake; J. Haruyama; T. Morota; Yuzuru Karouji; Nobuyuki Hasebe; Rumi Nakamura; Yujiro Ogawa; Tadashi Matsunaga


Archive | 2006

Morphology of Craters on Itokawa and Its Possible Implication

Naru Hirata; O. S. Barnouin-Jha; Chikatoshi Honda; Rumi Nakamura; Akiko M. Nakamura; Hirohide Demura; Tatsuhiro Michikami; Motoyuki Ishiguro; Takashi Hashimoto; Toru Kubota; J. Saito


Archive | 2011

Lunar Global Spectral Reflectance Data Set by Kaguya Spectral Profiler

Tadashi Matsunaga; Yusuke Yokota; S. Yamamoto; Rumi Nakamura; M. Ohtake; J. Haruyama


Archive | 2009

Lunar Phase Curve at Vis/NIR Wavelength Observed by SELENE Spectral Profiler

Yusuke Yokota; Tadashi Matsunaga; M. Ohtake; J. Haruyama; Yujiro Ogawa; Rumi Nakamura; Chikatoshi Honda; T. Morota; Kazuto Saiki; S. Kawabe; K. Nagasawa; Kohei Kitazato

Collaboration


Dive into the Rumi Nakamura's collaboration.

Top Co-Authors

Avatar

W. Baumjohann

Austrian Academy of Sciences

View shared research outputs
Top Co-Authors

Avatar

A. Runov

Austrian Academy of Sciences

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Tadashi Matsunaga

Tokyo University of Agriculture and Technology

View shared research outputs
Top Co-Authors

Avatar

Yusuke Yokota

Planetary Science Institute

View shared research outputs
Top Co-Authors

Avatar

J. Haruyama

National Space Development Agency of Japan

View shared research outputs
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar
Top Co-Authors

Avatar

Andris Vaivads

Swedish Institute of Space Physics

View shared research outputs
Researchain Logo
Decentralizing Knowledge