Japanese version here

List of Papers

1. A connection problem for Simpson's even family of rank four (with Katsuhisa Mimachi), to appear in Funk. Ekvac.
2. Topological theory for Selberg type integral associated with rigid Fuchsian systems (with Sho Hamaguchi), to appear in Math. Ann..
3. Middle convolution for completely integrable systems with logarithmic singularities along hyperplane arrangements, to appear in Adv. Stud. Pure Math..
4. Generating systems for finite irreducible complex reflection groups (with Mitsuo Kato), Funk. Ekvac., 53 (2010), 435-488.
5. Studies on deformation of Fuchsian systems from the viewpoint of rigidity, RIMS Kokyuroku Bessatsu B5 (2008), 51-60.
6. Rigidity for Appell's hypergeometric series F₄ (with Youichi Ueno), Funk. Ekvac. 51 (2008), 149-164.
7. Middle convolution and deformation for Fuchsian systems (with Galina Filipuk), J. London Math. Soc. 76 (2007), 438-450.
8. Construction of rigid local systems and integral representations of their sections (with Toshiaki Yokoyama), Math. Nachr.,279 (2006), 255-271.
9. On confluences of hypergeometric integrals, Kumamoto J. Math., 17 (2004), 1-8.
10. Evaluation of Stokes multipliers for a certain system of differential equations corresponding to a rigid local system, Funk. Ekvac., 46 (2003), 187-211.
11. Integral representations of solutions of differential equations free from accessory parameters, Adv. Math., 169 (2002), 187-240.
12. On rigidity of Pfaffian systems coming from Okubo systems (with Toshiaki Yokoyama), Kyushu J. Math., 55 (2001), 189-205.
13. Quadratic relations for confluent hypergeometric functions on Z_{2, n+1}, Funk. Ekvac., 42 (1999), 435-490.
14. Monodromy of an Okubo system with non-semisimple exponents, Funk. Ekvac., 40 (1997), 435-457.
15. Confluence of cycles for hypergeometric functions on Z_{2, n+1}, Trans. Amer. Math. Soc., 349 (1997), 675-712.
16. Irreducibility of accessory parameter free systems, Kumamoto J. Math., 8 (1995), 153-170.
17. Monodromy representations of systems of differential equations free from accessory parameters, SIAM J. Math. Anal., 25 (1994), 1595-1621.
18. Canonical forms of differential equations free from accessory parameters, SIAM J. Math. Anal., 25 (1994), 1203-1226.
19. Finite monodromy of Pochhammer equation, Ann. Inst. Fourier, 44 (1994), 767-810.
20. On contiguity relations of the confluent hypergeometric systems (with Hironobu Kimura and Kyoichi Takano), Proc. Japan Acad. 70, Ser. A (1994), 47-49.
21. On confluences of the general hypergeometric systems (with Hironobu Kimura and Kyoichi Takano), Proc. Japan Acad. 69, Ser. A (1993), 99-104.
22. Contiguity relations of generalized confluent hypergeometric functions (with Hironobu Kimura), Proc. Japan Acad. 69, Ser. A (1993), 105-110.
23. The generalized confluent hypergeometric functions (with Hironobu Kimura and Kyoichi Takano), Proc. Japan Acad. 68, Ser. A (1992), 290-295.
24. G-primitive extensions for linear ordinary differential equations, Kumamoto J. Math., 3 (1990), 1-9.
25. The Galois theory for linear homogeneous partial differential equations of the first order, Funk. Ekvac., 33 (1990), 79-126.
26. Theorems of Sibuya-Malgrange type for Gevrey functions of several variables, Funk. Ekvac., 32 (1989), 365-388.

I am studying on

• Construction of rigid local systems and study of their properties
• Characterization of differential equations coming from geometry
• General confluent hypergeometric functions in universal viewpoint
• Differential equations over fields of positive characteristics

Organizer

• "Invitation to Mathematics" Extenson Lectures at Kumamoto University (Every summer since1996)
• Seminar on Global Analysis at Kumamoto University
• "Various Aspects of Special Functions" Symposium at Kumamoto University, November 1992.
• "Deformation of differential equations and asymptotic analysis" Symposium at RIMS (Research Institute for Mathematical Sciences), 3-7 June 2002.
• "Studies on Accessory Parameters" Symposium at Kumamoto University, 20-22 June 2006.
• "Studies on Accessory Parameters" Symposium at Kumamoto University, 8-10 October 2007.