@article{oai:nipr.repo.nii.ac.jp:00010079,
 author = {Takasaki, S. and Sato, N. and Kadokura, A. and Yamagishi, H. and Kawano, H. and Ebihara, Y. and Tanaka, Y.-M. and Takasaki, S. and Sato, N. and Kadokura, A. and Yamagishi, H. and Kawano, H. and Ebihara, Y. and Tanaka, Y.-M.},
 issue = {2},
 journal = {Polar science, Polar science},
 month = {Jun},
 note = {In the austral summer of 2006-2007, the 48th Japanese Antarctic Research Expedition (JARE-48) installed two unmanned low-power magnetometers to form a closely spaced magnetometer network in combination with the permanent sites at Japan's Syowa Station in Antarctica. To identify field line resonances (FLRs), gradient methods are applied to the data from three adjacent sites in Antarctica and data from conjugate points in Antarctica and Iceland. By analyzing the data from the Antarctic and Icelandic sites individually, the structure of FLRs with high coherence is clearly identified. However, by analyzing the data from closely spaced Antarctic sites, it is more difficult to identify the signature of FLRs because of the inclusion of multiple signals related to the local geomagnetic pulsations over a broad frequency range. The frequency and resonance width of FLRs are determined by applying the amplitude phase gradient method (APGM) to the data from Antarctic sites. This yields the eigenfrequency as a continuous function of ground latitudes in the area surrounding Syowa Station. The mass density in the equatorial region at the L of the auroral zones is estimated from the obtained FLR frequency by numerically solving the standing Alfven wave equation. The mass density thus obtained is consistent with observational results from previous in situ measurements by spacecraft. The results of the present study demonstrate that data from geomagnetic conjugate points are helpful in identifying FLR in cases in which the magnetometers are too close to each other to enable identification. Once FLR is identified, APGM can be applied to the identified FLR, yielding the FLR frequency as a continuous function of ground latitudes. Therefore, the magnetospheric equatorial mass density is readily estimated with high spatial resolution., 第48次南極地域観測隊では昭和基地から70kmほど離れた南極大陸の内陸と沿岸部に衛星通信機能付き省電力磁力計（NIPR-LPM）を2台設置した。イリジウム衛星電話を経由したデータ収集システムにより、NIPR-LPMによる観測データは極夜期を除いて1日1回国立極地研究所に伝送される。南極に設置したNIPR-LPMによる磁場観測と、その磁場共役点アイスランド Tjornes での磁場観測から地球磁力線の定在振動を抽出した。さらに、経験値モデル（T04）で仮定した地球磁場と観測された周波数を磁力線の振動方程式に入力し、数値解析することによって磁気圏赤道域プラズマ密度の時空間変動を推定した。},
 pages = {73--86},
 title = {Interhemispheric observations of field line resonance frequencies as a continuous function of ground latitude in the auroral zones},
 volume = {2},
 year = {2008}
}