*Tatsuya Mizuta¹, Tomomi Okada¹, Martha K Savage², Ryota Takagi¹, Keisuke Yoshida¹, Hiroshi Yakiwara³, Takeshi Matsushima⁴, Hiroshi Katao⁵, Yoshiko Yamanaka⁶, Masahiro Kosuga⁷, Kei Katsumata⁸, Mako Ohzono⁸, Takashi NAKAYAMA¹, Satoshi Hirahara¹, Toshio Kono¹, Toru Matsuzawa¹, Group for the aftershock observations of the 2011 off the Pacific coast of Tohoku Earthquake (1.Tohoku University , 2.Victoria University of Wellington, 3.Kagoshima University, 4.kyushu University, 5.Kyoto University, 6.Nagoya University, 7.Hirosaki University, 8.Hokkaido University)

*Miu Matsuno¹, Tomomi Okada¹, Satoshi Matsumoto², Yuta Kawamura², Yoshihisa Iio³, Tadashi Sato¹, Takashi NAKAYAMA¹, Satoshi Hirahara¹, Stephen C Bannister⁴, John Ristau⁴, Martha K Savage⁵, Clifford Thurber⁶, Rick Sibson⁷ (1.Research Center for Prediction of Earthquakes and Volcanic Eruptions Graduate School of Science, Tohoku University, 2.Institute of Seismology and Volcanology, Faculty of Sciences, Kyushu University, 3.Disater Prevention Research Institute, Kyoto University, 4.GNS Science, Lower Hutt, New Zealand, 5.Victoria University of Wellington, Wellington, New Zealand, 6.University of Wisconsin, Madison, 7.University of Otago, Dunedin, New Zealand )

*Ayaka Tagami¹, Tomomi Okada¹, Shin'ichi Sakai², Mako Ohzono³, Kei Katsumata³, Masahiro Kosuga⁴, Yoshiko Yamanaka⁵, Hiroshi Katao⁶, Takeshi Matsushima⁷, Hiroshi Yakiwara⁸, Takashi NAKAYAMA¹, Satoshi Hirahara¹, Toshio Kono¹, Shu'ichiro Hori¹, Toru Matsuzawa¹, Group for the aftershock observations of the 2011 off the Pacific coast of Tohoku Earthquake (1.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University., 2.Earthquake Research Institute, University of Tokyo, 3.Institute of Seismology and Volcanology, Graduate School of Science, Hokkaido University, 4.Graduate School of Science and Technology, Hirosaki University, 5.Graduate School of Encironmental Studies, University of NAGOYA, 6.Research Center for Earthquake Prediction, Disaster Prevention Research Institute, Kyoto University, 7.Institute of Seismology and Volcanology, Faculty of Sciences, Kyushu University, 8.Nansei-toko Observatory for Earthquakes and Volcanoes, Kagoshima University)

*Tomomi Okada¹, Ayaka Tagami¹, Tatsuya Mizuta¹, Shin'ichi Sakai², Keisuke Yoshida¹, Naoki Uchida¹, Takashi NAKAYAMA¹, Satoshi Hirahara¹, Toru Matsuzawa¹ (1.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University, 2.ERI, University of Tokyo)

*Manami Suzuki ¹, Tomomi Okada¹, Akiko Hasemi¹, Toru Matsuzawa¹, Norihito Umino¹, Takashi NAKAYAMA¹, Noriko Tsumura², Tadashi Yamashina³, Group for the aftershock observations of the 2011 off the Pacific of Tohoku Earthquake (1.Research Center for Prediction of Earthquakes and Volcanic Eruptions, Graduate School of Science, Tohoku University, 2.Graduate School of Science, Chiba University, 3.Faculty of Science and Technology, Kochi University)