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Assistant Professor, Mathematical Institute, Tohoku University

Publications, preprints and notes.

Products of special values of L-functions and their applications Acta Arithmetica 116 (2005), 99--114.

Indivisibility of cental values of L-functions for modular forms  Proceedings of the American Mathematical Society 143 (2015), 2829--2840.

Simultaneous non-vanishing of modular L-functions   Archiv der Mathematik 83 (2007), 211--215.

Indivisibility of orders of Selmer groups for modular forms  International Journal of Number Theory 5 No2, 1--10 (2009).

On ordinary primes of modular forms and the theta operator   (joint work with Masanobu Kaneko) Proceedings of the American Mathematical Society 135 (2007), 1001--1005.

On the equivariant Tamagawa number conjecture for CM elliptic curves  RIMS Kokyuroku B4 (2007), 197--221.

On Teitelbaum type L-invariants of Hilbert modular forms attached to definite quaternions   (joint work with Chung Pang Mok and Jeehoon Park) Journal of Number Theory 147 (2015) 633--665.

On Fourier coefficients of Siegel modular forms of degree two with respect to congruence subgroups  (joint work with Hidenori Katsurada and Kohji Matsumoto) Abhandlungen aus dem Mathematischen Seminar der Universitat Hamburg 84 (2014) 31--47.

Special values of anticyclotomic L-functions for modular forms  (joint work with Ming-Lun Hsieh) to appear in Crelle's Journal.

On the rational K_2 of a curve of GL_2 type over a global field of positive characteristic  (joint work with Satoshi Kondo and Takuya Yamauchi) Journal of K-Theory 14 (2014) 313--342.

On the anticyclotomic Iwasawa main conjecture for modular forms   (joint work with Ming-Lun Hsieh) Compositio Mathematica 151 (2015), 863--893.

Selmer groups and central values of L-functions for modular forms   Annales de l'Institut Fourier 67 (2017), 1231--1276.

Regulators for Rankin-Selberg products of modular forms   (joint work with François Brunault) Annales des Sciences Mathématiques du Québec 40 (2016), no. 2, 221--249, Special issue marking the 60th birthday of Glenn Stevens.

Japanese Article

On congruences of modular forms and their applications (A survey paper, RIMS Kokyuroku, 2004/03/16, in Japanese)

Indivisibility of special values of L-functions and orders of Selmer groups for modular forms (Survey paper, Proceeding of Hakuba conference on automorphic forms, 2006/01/31)

Motives and special values of L-functions (Survey on Tamagawa number conjecture, in Japanese, 2006/02/21)

Hida families and Iwasawa main conjecture (Proof of Iwasawa Main conjecture using Hida families, in Japanese, 2006/02/21)